ip multicast survival guide part 2 - dfw cisco user group · 2016. 4. 6. · ip multicast survival...
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IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
IP Multicast Survival Guide Part 2
Second Edition
Beau WilliamsonCCIE 1356 R/S Emeritus
CiscoLive Distinguished Speakeraka “Multicast Survivorman”
Twitter: @Mr_Multicast
2IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Rules of Engagement“Silence . . . I kill you!”
– I mean your Cell Phones and Laptops that is.– Violators must buy Beer for everyone in the room!
Ask questions at any time.– 10,000 Bonus Points awarded for Good Questions– 20,000 Bonus Points awarded for Great Questions– 30,000 Bonus Point deduction for “intentionally” stumping presenter
• Remember: I haven’t touched this stuff in years so I’m a bit rusty.
3IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
To provide a “deep dive” into PIM ASM Protocol mechanics in order to provide you with a master IP Multicast survival toolkit that will help you to go alone and unafraid into the CCIE Lab Wilderness of IP Multicast1.
1You still may be asked to perform unnatural network acts in your CCIE lab.
Survival Guide Goal
4IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Agenda PIM ASM Review PIM Neighbor Discovery PIM State & State Rules PIM SSM Joining PIM SSM Pruning PIM ASM Joining PIM ASM Registering PIM ASM – SPT Switchover PIM ASM Pruning PIM Bidir Joining PIM Bidir Senders
Geekometer
5IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Review
6IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM Shared Tree Join
Receiver
RP
(*, G) JoinShared Tree
(*, G) State Created OnlyAlong the Shared Tree
7IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM Sender Registration
Receiver
RP
(S, G) Join
Source
(S, G) Register (unicast)Source Tree
(S, G) State Created OnlyAlong the Source TreeTraffic Flow
Shared Tree
8IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM Sender Registration
Receiver
RPSource
Shared TreeSource Tree RP Sends a Register-Stop Back
to the First-Hop Router to Stop the Register Process(S, G) Register-Stop (unicast)
Traffic Flow
(S, G) Register (unicast)
(S, G) Traffic Begins Arriving at the RP via the Source Tree
9IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM Sender Registration
Receiver
RPSource
Shared TreeSource Tree
Traffic FlowSource Traffic Flows NativelyAlong SPT to RPFrom RP, Traffic Flows Downthe Shared Tree to Receivers
10IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM SPT Switchover
Receiver
RP
(S, G) Join
Source
Source TreeShared Tree
Last-Hop Router Joins the Source TreeAdditional (S, G) State Is Created Along New Part of the Source Tree
Traffic Flow
11IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM SPT Switchover
Receiver
RPSource
Source TreeShared Tree
(S, G)RP-bit Prune
Traffic Begins Flowing Down the New Branch of the Source TreeAdditional (S, G) State Is Created Along the Shared Tree to Prune Off (S, G) Traffic
Traffic Flow
12IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM SPT Switchover
Receiver
RPSource
Source TreeShared Tree
(S, G) Traffic Flow Is Now Pruned Off of the Shared Tree and Is Flowing to the Receiver via the Source Tree
Traffic Flow
13IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM SPT Switchover
Receiver
RPSource
Source TreeShared Tree
(S, G) Traffic Flow Is No Longer Needed by the RP so It Prunes the Flow of (S, G) Traffic
Traffic Flow
(S, G) Prune
14IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM SPT Switchover
Receiver
RPSource
Source TreeShared Tree
(S, G) Traffic Flow Is Now Only Flowing to the Receiver via a Single Branch of the Source Tree
Traffic Flow
15IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Packets
16IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Packet Header
Ver:PIM Version = 2
Type:0 = Hello1 = Register (SM only)2 = Register-Stop (SM only)3 = Join/Prune4 = Bootstrap (SM BSR only)5 = Assert6 = Graft (DM only)7 = Graft-Ack (DM only)8 = C-RP-Announcement (SM BSR only)
PIMv2 is assigned protocol number 103317 153
• PIMv2 messages are multicast to the ALL-PIM-Routers (224.0.0.13) group with a TTL of 1.
Type Reserved ChecksumVer
For YourReference
17IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Hello Messages
Option Types:1 = Holdtime (Period of time in seconds before this PIM
neighbor times out.)19 = DR Priority20 = Generation ID
Type Reserved ChecksumVerOption LengthOption Type
Option Value
. . .
Option LengthOption TypeOption Value
317 153
For YourReference
18IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Join/Prune Packets
• Upstream Neighbor Address:IP address of RPF of upstream neighbor
• Holdtime:Period of time in seconds before this join/prune times out.
• Num. Grps# of Groups in Group list
• Group List:List (by group) of sources to Join and/or Prune.
Type Reserved ChecksumVerUpstream Neighbor Address (Encoded-Unicast)
Num. Groups HoldtimeReserved
Group List
317 153
For YourReference
19IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
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.
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PIM Group Lists
Group Lists are used in Join/Prune and Graft/Graft-Ack messages.
Num. Prune SourcesNum. Join SourcesGroup-1 (Encoded-Group)
3115
Join Source-1 (Encoded-Source)
Join Source-n (Encoded-Source)Prune Source-1 (Encoded-Source)
Prune Source-n (Encoded-Source)
Num. Prune SourcesNum. Join SourcesGroup-2 (Encoded-Group)
• Group-xGroup IP address
• Num. Join Sources# of Joins for Group-x
• Num. Prune Sources# of Prunes for Group-x
• Join/Prune Source-yEncoded Source address to be Joined/Pruned.
For YourReference
20IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Assert Packets
• Group Address:Identifies Group of the Assert
• Source Address:Identifies Source of the Assert
• R: (Sparse Mode Only)1 = Assert down RP Tree; 0 = Assert Down SPT
• Metric Preference:Admin. Distance of unicast routing protocol
• Metric:Unicast routing protocol metric
Type Reserved ChecksumVerGroup Address (Encoded-Group)
317 153
Source Address (Encoded-Source)Metric Preference
MetricR
For YourReference
21IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Register Packets
• B = Border Bit:Indicates DR is a border router performing a proxy-register
• N = Null Register Bit:Indicates DR is sending a Null-Register before expiring its register-suppression timer.
• Multicast Data Packet:The original packet sent by the source. For periodic sending of registers, this part is null.
Type Reserved ChecksumVerReserved
317 153
Multicast Data Packet
B N
Sparse Mode Only
For YourReference
22IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Register-Stop Packets
• Group Address:The Group address from the Register message.
• Source Address:IP host address of Source from multicast data packet in Register message.
Type Reserved ChecksumVerGroup Address (Encoded-Group)
317 153
Source Address (Encoded-Source)
Sparse Mode Only
For YourReference
23IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Encoded Unicast Addresses
Encoding Unicast Address . . .317 15
Addr Family. . . Unicast Address
• Addr Family:IANA Address Family Identifier (e.g. 1=IPv4)
• Encoding:Type of encoding within Address Family
• Unicast Address:Unicast Address of the target device.
For YourReference
24IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Source Address . . .
Encoded Source Addresses
Rsvd317 153
WREncodingAddr Family Mask LenS
• Addr Family:IANA Address Family Identifier (e.g. 1=IPv4)
• Encoding:Type of encoding within Address Family
• S = Sparse Mode bitIndicates Sparse Mode Group.
• W = Wildcard bitIndicates Join/Prune is a (*,G) Join/Prune.
• R = RP bitIndicates this Join/Prune should be sent up Shared Tree toward RP.
• Mask LenNumber of bits in the prefix of the Group Address.
• Source AddressAddress of Multicast Source
For YourReference
25IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Encoded Group Addresses
Group Address . . .Reserved
317 153
EncodingAddr Family Mask Len
• Addr Family:IANA Address Family Identifier (e.g. 1=IPv4)
• Encoding:Type of encoding within Address Family
• Mask LenNumber of bits in the prefix of the Group Address.
• Group AddressMulticast Group Address
For YourReference
26IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Neighbor Discovery
27IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
171.68.37.2PIM Router 2
Highest IP Address Electedas “DR” (Designated Router)
PIM Hello
PIM Router 1171.68.37.1
PIM Hello
PIM Neighbor Discovery
PIMv2 Hellos are periodically multicast to the “All-PIM-Routers” (224.0.0.13) group address (default = 30 seconds)
If the “DR” times-out, a new “DR” is elected The “DR” is responsible for sending all Joins and Register messages for any receivers or
senders on the network
28IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Neighbor Discovery - IOS
wan-gw8>show ip pim neighborPIM Neighbor TableNeighbor Interface Uptime/Expires Ver ModeAddress Prio/Mode171.68.0.70 FastEthernet0/0 2w1d/00:01:24 v2 1 / B S171.68.0.91 FastEthernet0/0 2w6d/00:01:01 v2 1 / B S171.68.0.82 FastEthernet0/0 7w0d/00:01:14 v2 5 / DR B S171.68.0.86 FastEthernet0/0 7w0d/00:01:13 v2 1 / B S171.68.0.80 FastEthernet0/0 7w0d/00:01:02 v2 1 / B S171.68.28.70 Serial2.31 22:47:11/00:01:16 v2 1 / B S171.68.28.50 Serial2.33 22:47:22/00:01:08 v2 1 / B S171.68.27.74 Serial2.36 22:47:07/00:01:21 v2 N /171.68.28.170 Serial0.70 1d4h/00:01:06 v2 N /171.68.27.2 Serial1.51 1w4d/00:01:25 v2 1 / B S171.68.28.110 Serial3.56 1d4h/00:01:20 v2 1 / B S171.68.28.58 Serial3.102 12:53:25/00:01:03 v2 1 / B S
29IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
DR Failover
Depends on neighbor expiration time Expiration time sent in PIM query messages
– Expiration time = 3 x <query-interval>– Default <query-interval> = 30 seconds– DR failover ~ 90 seconds (worst case) by default
A192.168.1.0/24.2 (DR) .1
Rtr-B>show ip pim neighborPIM Neighbor TableNeighbor Address Interface Uptime Expires Mode192.168.1.2 Ethernet0 4d22h 00:01:18 Sparse-Dense (DR)
B
00:01:18
30IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM State & State Rules
31IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM State Describes the “state” of the multicast distribution trees
– As understood by the router at that point in the network
Represented by multicast routing (mroute) table entries – Used to make multicast traffic forwarding decisions– Composed of (*, G) and (S, G) entries– Each entry contains RPF information
• Incoming (i.e. RPF) interface• RPF Neighbor (upstream)
– Each entry contains an Outgoing Interface List (OIL)• OIL may be NULL
32IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM State Example - IOS
sj-mbone> show ip mrouteFlags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,
L - Local, P - Pruned, R - RP-bit set, F - Register flag,T - SPT-bit set, J - Join SPT, M - MSDP created entry,X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement,U - URD, I - Received Source Specific Host Report
Outgoing interface flags: H - Hardware switchedTimers: Uptime/ExpiresInterface state: Interface, Next-Hop or VCD, State/Mode
(*, 224.1.1.1), 2w1d/00:00:00, RP 172.16.25.1, flags: SJCIncoming interface: Serial0/1, RPF nbr 172.16.4.1Outgoing interface list:Ethernet0/1, Forward/Sparse-Dense, 2w1d/00:01:40Serial0/0, Forward/Sparse-Dense, 00:4:52/00:02:08
(172.16.8.2, 224.1.1.1), 00:04:52/00:02:59, flags: CJTIncoming interface: Serial0/1, RPF nbr 172.16.4.1Outgoing interface list:Ethernet0/1, Forward/Sparse-Dense, 00:00:10/00:02:49Serial0/0, Forward/Sparse-Dense, 00:4:52/00:02:08
33IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM (*,G) State Rules in IOS (*,G) creation
– Receipt of a (*,G) Join or IGMP Report– Automatically if (S,G) must be created
– Not applicable to SSM
(*,G) reflects default group forwarding– IIF = RPF interface toward RP– OIL = interfaces
• That received a (*,G) Join or• With directly connected members or• Manually configured
(*,G) deletion– When OIL = NULL and– No child (S,G) state exists
34IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM (S,G) State Rules in IOS (S,G) creation
– By receipt of (S,G) Join or Prune or– By “Register” process– Parent (*,G) created (if doesn’t exist)
– Not applicable to SSM
(S,G) reflects forwarding of “S” to “G”– IIF = RPF Interface normally toward source
• RPF toward RP if “RP-bit” set– Not applicable to SSM
– OIL = Initially, copy of (*,G) OIL minus IIF– Not applicable to SSM
(S,G) deletion– By normal (S,G) entry timeout
35IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM OIL Rules in IOS Interfaces in OIL added
– By receipt of Join message• Interfaces added to (*,G) are added to all (S,G)’s
– Not applicable to SSM
Interfaces in OIL removed – By receipt of Prune message
• Interfaces removed from (*,G) are removed from all (S,G)’s– Not applicable to SSM
– Interface expire timer counts down to zero• Timer reset (to 3 min.) by receipt of periodic Join• or• By IGMP membership report
36IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM Triggered Join/Prune Rules Triggering Join/Prune Messages
– (*,G) Joins are triggered when:• The (*,G) OIL transitions from Null to non-Null
– (*,G) Prunes are triggered when:• The (*,G) OIL transitions from non-Null to Null
– (S,G) Joins are triggered when:• The (S,G) OIL transitions from Null to non-Null• The (S,G) RP bit is reset
– (S,G) Prunes are triggered when:• The (S,G) OIL transitions from non-Null to Null
– (S,G) RP-bit Prunes are triggered when:• The (S,G) RPF info != the (*,G) RPF info
– Not applicable to SSM
37IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM IOS State Flags S = Sparse C = Router has Directly Connected Host I = Router Received Source Specific Host Report (SSM) L = Local (Router is member) P = Pruned (All interfaces in OIL = Prune) T = Indicates at least one packet was forwarded via (S,G) entry
– Not applicable to SSM. “T” bit always set.
38IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM IOS State Flags J = Join SPT
– Not applicable to SSM– In (*, G) entry
• Indicates SPT-Threshold is being exceeded• Next (S,G) received will trigger join of SPT
– In (S, G) entry• Indicates SPT joined due to SPT-Threshold• If rate < SPT-Threshold, switch back to Shared Tree
F = Register/First-Hop – Not applicable to SSM
– In (S,G) entry• “S” is a directly connected source• Triggers the Register Process
– In (*, G) entry• Set when “F” set in at least one child (S,G)
39IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM-SM IOS State Flags R = RP bit
– Not applicable to SSM– (S, G) entries only– Set by (S,G)RP-bit Prune– Indicates info is applicable to Shared Tree– Used to prune (S,G) traffic from Shared Tree
• Initiated by Last-hop router after switch to SPT– Modifies (S,G) forwarding behavior
• IIF = RPF toward RP (I.e. up the Shared Tree)• OIL = Pruned accordingly
40IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Source-Specific Multicast (SSM)
41IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Source Specific Multicast (SSM) Uses Source Trees only Assumes one-to-many model
– Most Internet multicast fits this model– IP/TV also fits this model
Hosts responsible for source discovery– Typically via some out-of-band mechanism
• Web page, Content Server, etc.– Eliminates need for RP
• RP discovery (BSR, AutoRP, Static)• RP redundancy (BSR, AutoRP, MSDP, PIM-Anycast)• RP placement and nurturing
– Eliminates need for shared trees• SPT/RPT switchover complexity
– Eliminates need for interdomain PIM-SM complexity (MSDP)
42IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
SSM Overview Hosts join a specific source within a group
– Content identified by specific (S,G) instead of (*,G)– Hosts responsible for learning (S,G) information
Last-hop router sends (S,G) join toward source– Shared Tree is never Joined or used– Eliminates possibility of content Jammers– Only specified (S,G) flow is delivered to host
Eliminates Networked-Based Source Discovery– No RPs for SSM groups
Simplifies address allocation– Dissimilar content sources can use same group without fear of interfering with each other
43IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM SSM Joining
44IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM SSM Joining - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
(172.16.8.2, 232.1.1.1), 00:00:09/00:02:51, flags: sPTIncoming interface: Ethernet0/2, RPF nbr 0.0.0.0Outgoing interface list: Null
A
B CRcvr1 Rcvr2
Source Data
Source Tree10.1.3.2
10.1.3.1
172.16.8.1
45IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM SSM Joining - IOS
• Rcvr1 wishes to receive SSM S,G traffic. Sends IGMPv3 Join for S,G.1
IGMPv3 Join1
E0/2
E0/1
E0/1
Rcvr1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
A
B CRcvr2
Source Data
Source Tree10.1.3.2
10.1.3.1
172.16.8.1
46IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:00:14/00:02:45, flags: sTIIncoming interface: Ethernet0/0, RPF nbr 10.1.2.1Outgoing interface list:
B Creates (172.16.8.2, 224.1.1.1) State
PIM SSM Joining - IOS
Ethernet0/1, Forward/Sparse, 00:00:14/00:02:45
E0/2
E0/1
E0/1
Rcvr1
A
C
Src172.16.8.2
E0/1E0/0
B
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr2
Source Data
Source Tree10.1.3.2
10.1.3.1
172.16.8.1
47IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM SSM Joining - IOS
• B sends (S,G) Join towards Source.2
(S,G) Join 2
E0/0
E0/2
E0/1
E0/0E0/1
Rcvr1
10.1.2.2
10.1.2.1
A
C
Src172.16.8.2
E0/1E0/0
BRcvr2
Source Data
Source Tree10.1.3.2
10.1.3.1
172.16.8.1
48IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:00:15/00:02:49, flags: sTIncoming interface: Ethernet0/2, RPF nbr 0.0.0.0Outgoing interface list: Null
A Updates (172.16.8.2, 224.1.1.1) State
PIM SSM Joining - IOS
E0/0
E0/2
E0/1
E0/0E0/1
Rcvr1
10.1.2.2
10.1.2.1
C
Src172.16.8.2
E0/1E0/0
A
B
Ethernet0/0, Forward/Sparse, 00:28:03/00:02:43
Rcvr2
Source Data
Source Tree10.1.3.2
10.1.3.1
172.16.8.1
49IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Source Data
PIM SSM Joining - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
CRcvr1
A
BRcvr2
Source Tree10.1.3.2
10.1.3.1
172.16.8.1
50IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Source Data
PIM SSM Joining - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
CRcvr1
A
BRcvr2
Source Tree
IGMPv3 Join 3
• Rcvr2 wishes to receive SSM S,G traffic. Sends IGMPv3 Join for S,G.3
10.1.3.2
10.1.3.1
172.16.8.1
51IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Source Data
PIM SSM Joining - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1
A
BRcvr2
Source Tree
(172.16.8.2, 232.1.1.1), 00:00:02/00:02:49, flags: sTIIncoming interface: Ethernet0/0, RPF nbr 10.1.3.1Outgoing interface list:
C Creates (172.16.8.2, 224.1.1.1) State
C
10.1.3.2
10.1.3.1
Ethernet0/1, Forward/Sparse, 00:00:02/00:02:49
172.16.8.1
52IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Source Data
PIM SSM Joining - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1
A
BRcvr2
Source Tree
C
10.1.3.2
10.1.3.1(S,G) Join4
172.16.8.1
• C sends (S,G) Join towards Source.4
53IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:00:15/00:02:49, flags: sTIncoming interface: Ethernet0/2, RPF nbr 0.0.0.0Outgoing interface list:Ethernet0/0, Forward/Sparse, 00:28:03/00:02:43
A Updates (172.16.8.2, 224.1.1.1) StateEthernet0/1, Forward/Sparse, 00:00:03/00:02:48
Source Data
PIM SSM Joining - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B C
A
172.16.8.1
54IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Source Data
PIM SSM Joining - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
55IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM SSM Pruning
56IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:43:15/00:02:49, flags: sTIncoming interface: Ethernet0/2, RPF nbr 0.0.0.0Outgoing interface list:Ethernet0/0, Forward/Sparse, 00:43:15/00:02:44Ethernet0/1, Forward/Sparse, 00:40:03/00:02:55
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
State in A Before Pruning
57IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:43:15/00:02:49, flags: sTIIncoming interface: Ethernet0/0, RPF nbr 10.1.2.1Outgoing interface list:Ethernet0/1, Forward/Sparse, 00:43:15/00:02:44
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
State in B Before Pruning
58IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:40:16/00:02:49, flags: sTIIncoming interface: Ethernet0/0, RPF nbr 10.1.3.1Outgoing interface list:Ethernet0/1, Forward/Sparse, 00:40:16/00:02:42
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
State in C Before Pruning
59IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
• B is a Leaf router. Last Rcvr, leaves (S,G). 1
IGMP Leave1
60IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:43:25/00:02:49, flags: sTIIncoming interface: Ethernet0/0, RPF nbr 10.1.2.1Outgoing interface list:Ethernet0/1, Forward/Sparse, 00:00:14/00:02:45
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
• B removes E0/1 from (S,G) “oilist”.2
2
sTP
61IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:43:26/00:02:49, flags: sTIIncoming interface: Ethernet0/0, RPF nbr 10.1.2.1Outgoing interface list:Ethernet0/1, Forward/Sparse, 00:00:14/00:02:45
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
(S,G) Prune 3
• B’s (S,G) “oilist” now empty; triggers (S,G) Prune toward source.3
sTP
62IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:00:15/00:02:49, flags: sTIncoming interface: Ethernet0/2, RPF nbr 0.0.0.0Outgoing interface list:Ethernet0/0, Forward/Sparse, 00:28:03/00:02:43Ethernet0/1, Forward/Sparse, 00:00:03/00:02:48
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
(172.16.8.2, 232.1.1.1), 00:43:44/00:02:49, flags: sTIncoming interface: Ethernet0/2, RPF nbr 0.0.0.0Outgoing interface list:Ethernet0/1, Forward/Sparse, 00:00:03/00:02:48
• A removes E0/0 from (S,G) “oilist”.4
4
63IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
• C is a Leaf router. Last Rcvr, leaves (S,G). 5
IGMP Leave 5
64IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:43:45/00:02:49, flags: sTIIncoming interface: Ethernet0/0, RPF nbr 10.1.3.1Outgoing interface list:Ethernet0/1, Forward/Sparse, 00:00:02/00:02:49
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
sTP
• C removes E0/1 from (S,G) “oilist”.6
6
65IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
(S,G) Prune7
• C’s (S,G) “oilist” now empty; triggers (S,G) Prune toward source.7
66IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:43:46/00:02:49, flags: sTIncoming interface: Ethernet0/2, RPF nbr 0.0.0.0Outgoing interface list:Ethernet0/1, Forward/Sparse, 00:00:03/00:02:48
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
B
172.16.8.1
A
C
sTP
• A removes E0/1 from (S,G) “oilist”.8
8
67IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(172.16.8.2, 232.1.1.1), 00:43:48/00:00:04, flags: sTPIncoming interface: Ethernet0/0, RPF nbr 10.1.2.1Outgoing interface list:
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
172.16.8.1
A
C
After about 3 minutes . . .
B
(172.16.8.2, 232.1.1.1), 00:43:48/00:00:03, flags: sTPIncoming interface: Ethernet0/0, RPF nbr 10.1.2.1Outgoing interface list:
(172.16.8.2, 232.1.1.1), 00:43:48/00:00:02, flags: sTPIncoming interface: Ethernet0/0, RPF nbr 10.1.2.1Outgoing interface list:
(172.16.8.2, 232.1.1.1), 00:43:48/00:00:01, flags: sTPIncoming interface: Ethernet0/0, RPF nbr 10.1.2.1Outgoing interface list:
(172.16.8.2, 232.1.1.1), 00:43:48/00:00:00, flags: sTPIncoming interface: Ethernet0/0, RPF nbr 10.1.2.1Outgoing interface list:
68IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Source Data
PIM SSM Pruning - IOS
E0/2
E0/1
E0/1
Src172.16.8.2
E0/1E0/0
E0/0
E0/010.1.2.2
10.1.2.1
Rcvr1 Rcvr2
Source Tree10.1.3.2
10.1.3.1
172.16.8.1
A
C
(S, G) State times out
(172.16.8.2, 232.1.1.1), 00:43:48/00:00:00, flags: sTPIncoming interface: Ethernet0/0, RPF nbr 10.1.2.1Outgoing interface list:
B
After about 3 minutes . . .Same for routers C and A
69IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Any-Source Multicast (ASM)
70IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Joining
71IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Shared Tree
PIM ASM Joining - IOS
• Rcvr wishes to receive group G traffic. Sends IGMP Join for G.1
IGMP Join1
E0S0
S1
E0E1
Rcvr
To RP (10.1.5.1)
10.1.2.2
10.1.2.110.1.4.2
A
B
72IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:00:05/00:00:00, RP 10.1.5.1, flags: SCIncoming interface: Ethernet0, RPF nbr 10.1.2.1Outgoing interface list:
E0S0
S1
E0E1
Rcvr
To RP (10.1.5.1)
10.1.2.2
10.1.2.110.1.4.2
B Creates (*, 224.1.1.1) State
PIM ASM Joining - IOS
Ethernet1, Forward/Sparse-Dense, 00:00:05/00:02:54
Shared Tree
A
B
73IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
E0S0
S1
E0E1
Rcvr
To RP (10.1.5.1)
10.1.2.2
10.1.2.110.1.4.2
PIM ASM Joining - IOS
• Rcvr wishes to receive group G traffic. Sends IGMP Join for G.1
• B sends (*,G) Join towards RP.2
(*,G) Join2
Shared Tree
A
B
74IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:00:05/00:00:00, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.4.1Outgoing interface list:
E0S0
S1
E0E1
Rcvr
To RP (10.1.5.1)
10.1.2.2
10.1.2.110.1.4.2
A Creates (*, 224.1.1.1) State
PIM ASM Joining - IOS
Ethernet0, Forward/Sparse-Dense, 00:00:05/00:02:54
Shared Tree
A
B
75IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
E0S0
S1
E0E1
Rcvr
To RP (10.1.5.1)
10.1.2.2
10.1.2.110.1.4.2
PIM ASM Joining - IOS
• A sends (*,G) Join towards RP.3
• Rcvr wishes to receive group G traffic. Sends IGMP Join for G.1
• B sends (*,G) Join towards RP.2
(*,G) Join3
• Shared tree is built all the way back to the RP.4
Shared Tree4
Shared Tree
A
B
76IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Registering
77IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Register Scenarios Receivers Join Group First Source Registers First Receivers along the SPT
78IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Registering –Receiver Joins First
79IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
State in “RP” Before Any Source Registers(With Receivers on Shared Tree)
RP
Shared Tree
S3S0 S1
PIM ASM Registering - IOSReceiver Joins Group First
E0 S1S0S0A B
(*, 224.1.1.1), 00:03:14/00:00:00, RP 171.68.28.140, flags:SIncoming interface: Null, RPF nbr 0.0.0.0,Outgoing interface list:Serial0, Forward/Sparse-Dense, 00:03:14/00:03:15Serial1, Forward/Sparse-Dense, 00:03:14/00:03:15
C
80IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
State in B Before Any Source Registers(With Receivers on Shared Tree)
PIM ASM Registering - IOSReceiver Joins Group First
rtr-b>sh ip mroute 224.1.1.1
No such group
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
81IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
State in A Before Any Source Registers(With Receivers on Shared Tree)
PIM ASM Registering - IOSReceiver Joins Group First
rtr-a>sh ip mroute 224.1.1.1
No such group.
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
82IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(171.68.37.121, 224.1.1.1)Mcast Packets
Source171.68.37.121
PIM ASM Registering - IOSReceiver Joins Group First
• Source begins sending group G traffic. 1
1 RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
83IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:00:03/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial0, RPF nbr 171.68.28.191,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:00:03/00:02:56, flags: FPTIncoming interface: Ethernet0, RPF nbr 0.0.0.0, Outgoing interface list: Null
A Creates (S, G) State for Source(After Automatically Creating a (*, G) entry)
PIM ASM Registering - IOSReceiver Joins Group First
Registering
• Source begins sending group G traffic. 1
• A encapsulates packets in Registers; unicasts to RP.2
Register Msgs2(171.68.37.121, 224.1.1.1)Mcast Packets
Source171.68.37.121
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
FPT
84IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
“RP” Processes Register; Creates (S, G) State
PIM ASM Registering - IOSReceiver Joins Group First
• RP (C) de-encapsulates packets; forwards down Shared tree.3
(*, 224.1.1.1)Mcast Traffic
3
(*, 224.1.1.1), 00:09:21/00:00:00, RP 171.68.28.140, flags: SIncoming interface: Null, RPF nbr 0.0.0.0,Outgoing interface list:Serial0, Forward/Sparse-Dense, 00:09:21/00:02:38Serial1, Forward/Sparse-Dense, 00:03:14/00:02:46
(171.68.37.121, 224.1.1.1, 00:01:15/00:02:46, flags:Incoming interface: Serial3, RPF nbr 171.68.28.139,Outgoing interface list:Serial0, Forward/Sparse-Dense, 00:00:49/00:02:11Serial1, Forward/Sparse-Dense, 00:00:49/00:02:11
Register Msgs(171.68.37.121, 224.1.1.1)Mcast Packets
Source171.68.37.121
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
171.68.28.139
85IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
171.68.28.139
PIM ASM RegisteringReceiver Joins Group First
• RP sends (S,G) Join toward Source to build SPT.4
(S,G) Join 4
Register Msgs(171.68.37.121, 224.1.1.1)Mcast Packets
Source171.68.37.121
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
(*, 224.1.1.1)Mcast Traffic
86IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
B Processes Join, Creates (S, G) State(After Automatically Creating the (*, G) Entry)
PIM ASM Registering - IOSReceiver Joins Group First
• B sends (S,G) Join toward Source to continue building SPT.5
(S,G) Join 5
(*, 224.1.1.1), 00:04:28/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial1, RPF nbr 171.68.28.140,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:04:28/00:01:32, flags: Incoming interface: Serial0, RPF nbr 171.68.28.190Outgoing interface list:
Register Msgs(171.68.37.121, 224.1.1.1)Mcast Packets
Source171.68.37.121
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
(*, 224.1.1.1)Mcast Traffic
Serial1, Forward/Sparse-Dense, 00:04:28/00:01:32
171.68.28.190
87IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
A Processes the (S, G) Join; Adds Serial0 to OIL
PIM ASM Registering - IOSReceiver Joins Group First
(*, 224.1.1.1), 00:04:28/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial0, RPF nbr 171.68.28.191,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:04:28/00:01:32, flags: FTIncoming interface: Ethernet0, RPF nbr 0.0.0.0, RegisteringOutgoing interface list:
Register Msgs(171.68.37.121, 224.1.1.1)Mcast Packets
Source171.68.37.121
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
Serial0, Forward/Sparse-Dense, 00:04:28/00:01:32
(*, 224.1.1.1)Mcast Traffic
88IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM RegisteringReceiver Joins Group First
• RP begins receiving (S,G) traffic down SPT. 6
6
Register Msgs(171.68.37.121, 224.1.1.1)Mcast Packets
Source171.68.37.121
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
(*, 224.1.1.1)Mcast Traffic
89IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:09:21/00:00:00, RP 171.68.28.140, flags: SIncoming interface: Null, RPF nbr 0.0.0.0,Outgoing interface list:Serial0, Forward/Sparse-Dense, 00:09:21/00:02:38Serial1, Forward/Sparse-Dense, 00:03:14/00:02:46
(171.68.37.121, 224.1.1.1, 00:01:15/00:02:46, flags:TIncoming interface: Serial3, RPF nbr 171.68.28.139,Outgoing interface list:Serial0, Forward/Sparse-Dense, 00:00:49/00:02:11Serial1, Forward/Sparse-Dense, 00:00:49/00:02:11
Traffic Arriving via SPT Is Forwarded Down Shared Tree(This Causes the “T” Flag to Be Set)
PIM ASM Registering - IOSReceiver Joins Group First
T
Register Msgs(171.68.37.121, 224.1.1.1)Mcast Packets
Source171.68.37.121
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
Note “T”FlagIs Now Set
(*, 224.1.1.1)Mcast Traffic
90IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Register-Stop
PIM ASM Registering - IOSReceiver Joins Group First
• Once “T” Flag is set, next “Register” causes RP to send back a “Register-Stop” to A
7
Register Msgs(171.68.37.121, 224.1.1.1)Mcast Packets
Source171.68.37.121
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
(*, 224.1.1.1)Mcast Traffic
91IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:04:28/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial0, RPF nbr 171.68.28.191,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:04:28/00:01:32, flags: FTIncoming interface: Ethernet0, RPF nbr 0.0.0.0, RegisteringOutgoing interface list:Serial0, Forward/Sparse-Dense, 00:04:28/00:01:32
PIM ASM Registering - IOSReceiver Joins Group First
A Stops Sending Register Messages(Final State in A)
• (S,G) Traffic now flowing down a single path (SPT) to RP.8
8
Register-Stop
Register Msgs(171.68.37.121, 224.1.1.1)Mcast Packets
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
(*, 224.1.1.1)Mcast Traffic
Source171.68.37.121
92IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Final State in B
PIM ASM Registering - IOSReceiver Joins Group First
(*, 224.1.1.1), 00:04:28/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial1, RPF nbr 171.68.28.140,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:04:28/00:01:32, flags: T Incoming interface: Serial0, RPF nbr 171.68.28.190Outgoing interface list:Serial1, Forward/Sparse-Dense, 00:04:28/00:01:32
(171.68.37.121, 224.1.1.1)Mcast Packets
Source171.68.37.121
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
(*, 224.1.1.1)Mcast Traffic
93IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Final State in the “RP”(With Receivers on Shared Tree)
PIM ASM Registering - IOSReceiver Joins Group First
(*, 224.1.1.1), 00:09:21/00:00:00, RP 171.68.28.140, flags: SIncoming interface: Null, RPF nbr 0.0.0.0,Outgoing interface list:Serial0, Forward/Sparse-Dense, 00:09:21/00:02:38Serial1, Forward/Sparse-Dense, 00:03:14/00:02:46
(171.68.37.121, 224.1.1.1, 00:01:15/00:02:46, flags: TIncoming interface: Serial3, RPF nbr 171.68.28.139,Outgoing interface list:Serial0, Forward/Sparse-Dense, 00:00:49/00:02:11Serial1, Forward/Sparse-Dense, 00:00:49/00:02:11
(171.68.37.121, 224.1.1.1)Mcast Packets
Source171.68.37.121
RP
Shared Tree
S0 S1A B CS3E0 S1S0S0
(*, 224.1.1.1)Mcast Traffic
94IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Registering –Source Registers First
95IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
rtr-c>show ip mroute 224.1.1.1
Group 224.1.1.1 not found.
State in “RP” before Registering(Without Receivers on Shared Tree)
PIM ASM Registering - IOSSource Registers First
RP
S3S0
S1S0S0E0S1
A B C
96IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
rtr-b>show ip mroute 224.1.1.1
Group 224.1.1.1 not found.
State in B Before Any Source Registers(With Receivers on Shared Tree)
RP
S3S0
S1S0S0E0S1
A B C
PIM ASM Registering - IOSSource Registers First
97IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
rtr-a>show ip mroute 224.1.1.1
Group 224.1.1.1 not found.
State in A Before Any Source Registers(With Receivers on Shared Tree)
RP
S3S0
S1S0S0E0S1
A B C
PIM ASM Registering - IOSSource Registers First
98IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
Source171.68.37.121
PIM ASM Registering - IOSSource Registers First
S3S0
S1S0S0E0S1
1
A B C
• Source begins sending group G traffic. 1
99IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:00:03/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial0, RPF nbr 171.68.28.191,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:00:03/00:02:56, flags: FPTIncoming interface: Ethernet0, RPF nbr 0.0.0.0,Outgoing interface list: Null
A Creates (S, G) State for Source(After Automatically Creating a (*, G) Entry)
PIM ASM Registering - IOSSource Registers First
• Source begins sending group G traffic. 1
• A encapsulates packets in Registers; unicasts to RP.2
Register Msgs2(171.68.37.121, 224.1.1.1)Mcast Packets
RP
Source171.68.37.121
S3S0
S1S0S0E0S1
A B C
Registering
100IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:15/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Null, RPF nbr 0.0.0.0,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:01:15/00:01:45, flags: PIncoming interface: Serial3, RPF nbr 171.68.28.139,Outgoing interface list: Null
“RP” Processes Register; Creates (S, G) State(After Automatically Creating the (*, G) Entry)
PIM ASM Registering - IOSSource Registers First
• RP (C) has no receivers on Shared Tree; discards packet.3
3
Register Msgs(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
101IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Registering - IOSSource Registers First
• RP sends “Register-Stop” to A.4
Register-Stop4
Register Msgs(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
102IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Registering - IOSSource Registers First
• A stops encapsulating traffic in Register Messages;drops packets from Source.
5
5
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
103IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:28/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial0, RPF nbr 171.68.28.191,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:01:28/00:01:32, flags: FPTIncoming interface: Ethernet0, RPF nbr 0.0.0.0Outgoing interface list: Null
State in A After Registering(Without Receivers on Shared Tree)
PIM ASM Registering - IOSSource Registers First
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
104IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
State in B after A Registers(Without Receivers on Shared Tree)
PIM ASM Registering - IOSSource Registers First
rtr-b>show ip mroute 224.1.1.1
Group 224.1.1.1 not found.
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
105IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:15/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Null, RPF nbr 0.0.0.0,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:01:15/00:01:45, flags: PIncoming interface: Serial3, RPF nbr 171.68.28.139,Outgoing interface list: Null
State in RP After A Registers(Without Receivers on Shared Tree)
171.68.28.139
PIM ASM Registering - IOSSource Registers First
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
106IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Registering - IOSSource Registers First
• RP (C) receives (*, G) Join from a receiver on Shared Tree. 6
(*, G) Join6
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
107IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:09:21/00:00:00, RP 171.68.28.140, flags: SIncoming interface: Null, RPF nbr 0.0.0.0,Outgoing interface list:
(171.68.37.121, 224.1.1.1, 00:01:15/00:02:46, flags: TIncoming interface: Serial3, RPF nbr 171.68.28.139,Outgoing interface list:
RP Processes (*,G) Join(Adds Serial1 to Outgoing Interface Lists)
PIM ASM Registering - IOSSource Registers First
Serial1, Forward/Sparse-Dense, 00:00:14/00:02:46
Serial1, Forward/Sparse-Dense, 00:00:14/00:02:46
• RP sends (S,G) Joins for all known Sources in Group.7
7(S, G) Join
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
108IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:04:28/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial1, RPF nbr 171.68.28.140,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:04:28/00:01:32, flags: Incoming interface: Serial0, RPF nbr 171.68.28.190Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:04:28/00:01:32
B Processes Join, Creates (S, G) State(After Automatically Creating the (*, G) Entry)
171.68.28.190
PIM ASM Registering - IOSSource Registers First
• B sends (S,G) Join toward Source to continue building SPT.8
(S, G) Join8
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
109IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:04:28/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial0, RPF nbr 171.68.28.191,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:04:28/00:01:32, flags: FTIncoming interface: Ethernet0, RPF nbr 0.0.0.0, Outgoing interface list:
A Processes the (S, G) Join; Adds Serial0 to OIL
Serial0, Forward/Sparse-Dense, 00:04:28/00:01:32
PIM ASM Registering - IOSSource Registers First
• RP begins receiving (S,G) traffic down SPT.9
9
• RP forwards (S,G) traffic down Shared Tree to receivers.10
(*, 224.1.1.1)Mcast Traffic
10
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
110IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:04:28/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial0, RPF nbr 171.68.28.191,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:04:28/00:01:32, flags: FTIncoming interface: Ethernet0, RPF nbr 0.0.0.0, Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:04:28/00:01:32
Final state in Router A
PIM ASM Registering - IOSSource Registers First
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
(*, 224.1.1.1)Mcast Traffic
111IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:04:28/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial1, RPF nbr 171.68.28.140,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:04:28/00:01:32, flags: TIncoming interface: Serial0, RPF nbr 171.68.28.190Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:04:28/00:01:32
Final State in B After Receivers Join
171.68.28.190
PIM ASM Registering - IOSSource Registers First
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
(*, 224.1.1.1)Mcast Traffic
112IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:09:21/00:00:00, RP 171.68.28.140, flags: SIncoming interface: Null, RPF nbr 0.0.0.0,Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:03:14/00:02:46
(171.68.37.121, 224.1.1.1, 00:01:15/00:02:46, flags: TIncoming interface: Serial3, RPF nbr 171.68.28.139,Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:00:49/00:02:11
Final State in RP After Receivers Join
PIM ASM Registering - IOSSource Registers First
(171.68.37.121, 224.1.1.1)Mcast Packets
RP
S3S0
S1S0S0E0S1
A B CSource171.68.37.121
171.68.28.139
(*, 224.1.1.1)Mcast Traffic
113IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Registering –Receiver Along the SPT
114IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:04:28/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial0, RPF nbr 171.68.28.191,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:04:28/00:01:32, flags: FTIncoming interface: Ethernet0, RPF nbr 0.0.0.0, Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:04:28/00:01:32
Current state in Router A
PIM ASM Registering - IOSReceivers Along the SPT
RP
Source171.68.37.121
(171.68.37.121, 224.1.1.1)Mcast Packets
(*, 224.1.1.1)Mcast Traffic
S0 S1 S3
S1A B
Shared Tree
CS0E0
115IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:04:28/00:00:00, RP 171.68.28.140, flags: SPIncoming interface: Serial1, RPF nbr 171.68.28.140,Outgoing interface list: Null
(171.68.37.121, 224.1.1.1), 00:04:28/00:01:32, flags: TIncoming interface: Serial0, RPF nbr 171.68.28.190Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:04:28/00:01:32
Current State in B
RP
Source171.68.37.121
(171.68.37.121, 224.1.1.1)Mcast Packets
(*, 224.1.1.1)Mcast Traffic
PIM ASM Registering - IOSReceivers Along the SPT
S1A B
Shared Tree
CS0 S1 S3S0E0
116IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:09:21/00:00:00, RP 171.68.28.140, flags: SIncoming interface: Null, RPF nbr 0.0.0.0,Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:03:14/00:02:46
(171.68.37.121, 224.1.1.1, 00:01:15/00:02:46, flags: TIncoming interface: Serial3, RPF nbr 171.68.28.139,Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:00:49/00:02:11
Current State in the RP
PIM ASM Registering - IOSReceivers Along the SPT
RP
Source171.68.37.121
(171.68.37.121, 224.1.1.1)Mcast Packets
(*, 224.1.1.1)Mcast Traffic
S1A B
Shared Tree
CS0 S1 S3S0E0
117IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Registering - IOSReceivers Along the SPT
• Rcvr wishes to receive group G traffic. Sends IGMP Join for G.1
RP
Source171.68.37.121
(171.68.37.121, 224.1.1.1)Mcast Packets
(*, 224.1.1.1)Mcast Traffic
S1A
E0
Rcvr
B
IGMP Join1
Shared Tree
CS0 S1 S3S0E0
118IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:04:28/00:00:00, RP 171.68.28.140, flags: SCIncoming interface: Serial1, RPF nbr 171.68.28.140,Outgoing interface list:
(171.68.37.121, 224.1.1.1), 00:04:28/00:01:32, flags: CTIncoming interface: Serial0, RPF nbr 171.68.28.190Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:04:28/00:01:32
B adds Ethernet0 to (*,G) and (S,G) OIL’s
PIM ASM Registering - IOSReceivers Along the SPT
Ethernet0, Forward/Sparse-Dense, 00:00:30/00:02:30
Ethernet0, Forward/Sparse-Dense, 00:00:30/00:02:30
RP
Source171.68.37.121
(171.68.37.121, 224.1.1.1)Mcast Packets
(*, 224.1.1.1)Mcast Traffic
S1A
E0
Rcvr
B
Shared Tree
C
• Traffic begins flowing to Rcvr via (S,G)2
S0 S1 S3S0E0
2
119IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
E0
Rcvr
PIM ASM Registering - IOSReceivers Along the SPT
• B triggers a (*,G) Join to join the Shared Tree3
(*, G) Join2
RP
Source171.68.37.121
(171.68.37.121, 224.1.1.1)Mcast Packets
(*, 224.1.1.1)Mcast Traffic
S1A
Shared Tree
CS0 S1 S3S0E0 B
120IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:09:21/00:00:00, RP 171.68.28.140, flags: SIncoming interface: Null, RPF nbr 0.0.0.0,Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:03:14/00:02:46
(171.68.37.121, 224.1.1.1, 00:01:15/00:02:46, flags: TIncoming interface: Serial3, RPF nbr 171.68.28.139,Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:00:49/00:02:11
RP adds Serial3 to (*,G) OIL
PIM ASM Registering - IOSReceivers Along the SPT
Serial3, Forward/Sparse-Dense, 00:00:10/00:02:50
E0
Rcvr
RP
Source171.68.37.121
(171.68.37.121, 224.1.1.1)Mcast Packets
(*, 224.1.1.1)Mcast Traffic
S1A B C
Shared Tree
S0 S1 S3S0E0
Pop Quiz:Why didn’t it copy Serial3 to theOIL of the (S,G) entry?
121IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Registering - IOSReceivers Along the SPT
• Other Group G traffic can now flow to Rcvr via Shared Tree.(Note: 171.68.37.121 traffic doesn’t flow to RP then back down to B)
4
E0
Rcvr
RP
Source171.68.37.121
(171.68.37.121, 224.1.1.1)Mcast Packets
(*, 224.1.1.1)Mcast Traffic
S1A B C
Shared Tree
S0 S1 S3S0E0
122IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM – SPT Switchover
123IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM SPT-Switchover - IOS SPT Thresholds may be set for any Group
– Access Lists may be used to specify which Groups– Default Threshold = 0kbps (I.e. immediately join SPT)– Threshold = “infinity” means “never join SPT”– Don’t use values in between “0” and “infinity”– (In IOS XR, “0” and “infinity” are the only options)
Threshold triggers Join of Source Tree– Sends an (S,G) Join up SPT for next “S” in “G” packet received
124IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.5.1,Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:01:43/00:02:11Serial2, Forward/Sparse-Dense, 00:00:32/00:02:28
State in C Before Switch
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
Rcvr B
S2
S0
PIM ASM SPT-Switchover - IOS
A
B
C
D
Shared Tree
125IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: SCIncoming interface: Serial0, RPF nbr 10.1.4.9,Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:43/00:02:11
State in D Before Switch
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
Rcvr B
S2
S0
A
B
Shared Tree
C
D
126IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:43/00:02:11
State in A Before Switch
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
Rcvr B
S2
S0
A
B
Shared Tree
C
D
127IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: SCJIncoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:43/00:02:11
State in B Before Switch
PIM ASM SPT-Switchover - IOS
Note “J”Flag is set
J
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
Rcvr B
S2
S0
A
B
C
Shared Tree
D
128IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: SCJIncoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:43/00:02:11
PIM ASM SPT-Switchover - IOS
• New source (Si,G) packet arrives down Shared tree.1
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
Rcvr B
S2
S0
A
B
C
D1
(Si, G) Traffic FlowShared Tree Flow
129IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: SCJIncoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:43/00:02:11
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SCJIncoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:43/00:02:11
(171.68.37.121, 224.1.1.1), 00:00:28/00:02:51, flags: CJ Incoming interface: Ethernet0, RPF nbr 10.1.2.1Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:00:28/00:02:32
PIM ASM SPT-Switchover - IOS
• Because of “C” bit, B creates (Si,G) state to cut over to SPT.2
2
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
Rcvr B
S2
S0
A
B
C
D (Si, G) Traffic FlowShared Tree Flow
130IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM SPT-Switchover - IOS
• B sends (Si,G) Join towards Si .3
(Si,G) Join3
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
Rcvr B
S2
S0
A
B
C
D (Si, G) Traffic FlowShared Tree Flow
131IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:43/00:02:11
(171.68.37.121, 224.1.1.1), 00:13:28/00:02:53, flags: Incoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:13:25/00:02:30
A creates (Si,G) state
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
Rcvr B
S2
S0
A
B
C
D (Si, G) Traffic FlowShared Tree Flow
132IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM SPT-Switchover - IOS
• A triggers (Si,G) Join toward Si.4
(Si,G) Join4
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
Rcvr B
S2
S0
A
B
C
D
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
133IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM SPT-Switchover - IOS
• (Si, G) traffic begins flowing down SPT tree instead of Shared Tree.5
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
Rcvr B
S2
S0
C
D
• A triggers (Si,G) Join toward Si.4
A
B SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
134IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:43/00:02:11
(171.68.37.121, 224.1.1.1), 00:13:28/00:02:53, flags: Incoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:13:25/00:02:30
PIM ASM SPT-Switchover - IOS
“T”Flag Set by Arriving Traffic on SPT
T
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
D
A
B
Rcvr B
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
135IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:43/00:02:11
(171.68.37.121, 224.1.1.1), 00:13:28/00:02:53, flags: Incoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:13:25/00:02:30
PIM ASM SPT-Switchover - IOS
• Once T Flag is set, A triggers (Si,G)RP-bit Prunes toward RP.6
(Si,G)RP-bit Prune6
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
D
A
B
Note RPF Info Does Not Match. This Indicates SPT and RPT Diverge.
Rcvr B
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
136IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.5.1,Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:01:43/00:02:11Serial2, Forward/Sparse-Dense, 00:00:32/00:02:28
C creates (Si, G) RP-bit State and removes Serial1 from (Si, G)
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
DB
A
Note: Because “R” bit is set, Incoming interface points to RP not Source.
(171.68.37.121, 224.1.1.1), 00:13:28/00:02:53, flags: R Incoming interface: Serial0, RPF nbr 10.1.5.1Outgoing interface list:
Serial2, Forward/Sparse-Dense, 00:00:32/00:02:28
Rcvr B
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
137IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM SPT-Switchover - IOS
• Unnecessary (Si, G) traffic is pruned from the Shared tree.7
7E0
S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
D
A
B
Rcvr B
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
138IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SCJIncoming interface: Serial0, RPF nbr 10.1.4.9,Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:43/00:02:11
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
D
A
B
Rcvr B
• Because of “C” bit, D also creates (Si,G) state to cut over to SPT.8
(171.68.37.121, 224.1.1.1), 00:00:28/00:02:51, flags: CJ Incoming interface: Serial0, RPF nbr 10.1.3.1Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:00:28/00:02:32
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
139IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
D
A
B
Rcvr B
• D triggers (Si,G) Join toward Si.9
(Si,G) Join9
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
140IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.5.1,Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:01:43/00:02:11Serial2, Forward/Sparse-Dense, 00:00:32/00:02:28
(171.68.37.121, 224.1.1.1), 00:13:28/00:02:53, flags: R Incoming interface: Serial0, RPF nbr 10.1.5.1Outgoing interface list:
Serial2, Forward/Sparse-Dense, 00:00:32/00:02:28
C resets (Si, G) RP-bit State
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
DB
A
Rcvr B
Serial1, RPF nbr 10.1.4.2
and RPF’s (Si, G) toward Source.
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
141IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
DB
A
Rcvr B
• C triggers (Si,G) Join toward Si.10
(Si,G) Join10
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
142IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:43/00:02:11
(171.68.37.121, 224.1.1.1), 00:13:28/00:02:53, flags: Incoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:13:25/00:02:30
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
DB
A
Rcvr B
A adds Serial0 to (Si,G) OILSerial0, Forward/Sparse-Dense, 00:13:25/00:02:30
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
143IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
B
A
Rcvr B
Traffic flows to Rcvr B via SPT.
D
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
144IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.5.1,Outgoing interface list:
Serial1, Forward/Sparse-Dense, 00:01:43/00:02:11Serial2, Forward/Sparse-Dense, 00:00:32/00:02:28
(171.68.37.121, 224.1.1.1), 00:13:28/00:02:53, flags:TIncoming interface: Serial1, RPF nbr 10.1.4.2Outgoing interface list:
Serial2, Forward/Sparse-Dense, 00:00:32/00:02:28
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
B
A
Rcvr B
D
Note RPF Info Does Not Match. This Indicates SPT and RPT Diverge.
• Once T Flag is set, C triggers (Si,G)RP-bit Prunes toward RP.11
(Si,G)RP-bit Prune
11
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
145IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
B
A
Rcvr B
D
All (Si,G) Traffic pruned from Shared Tree.
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
146IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM SPT-Switchover - IOS
E0S0
S1
E0E1
Rcvr A
10.1.2.2
10.1.2.110.1.4.2
S110.1.4.1 To Source “Si”
To RP (10.1.5.1)S0
E0
S2
S0
C
B
A
Rcvr B
But what does the Shared Tree look like now?
Shared Tree
D
Don’t confuse Forwarding State with Tree Topology!
SPT Tree Flow
(Si, G) Traffic FlowShared Tree Flow
147IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Pruning
148IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: SCIncoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:43/00:02:11
State in B Before Pruning
S1
E1
Rcvr A
To RP (10.1.5.1)
(Si, G) Traffic FlowShared TreeSPT Tree
PIM ASM Pruning - IOS Shared Tree Case
A
B
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
149IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:43/00:02:11
State in A Before Pruning
PIM ASM Pruning - IOS Shared Tree Case
S1
E1
Rcvr A
To RP (10.1.5.1)
(Si, G) Traffic FlowShared TreeSPT Tree
A
B
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
150IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Pruning - IOS Shared Tree Case
• B is a Leaf router. Last Rcvr, leaves group G. 1
IGMP Leave1
S1
E1
Rcvr A
To RP (10.1.5.1)
(Si, G) Traffic FlowShared TreeSPT Tree
A
B
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
151IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: SIncoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:43/00:02:11
PIM ASM Pruning - IOS Shared Tree Case
• B removes Ethernet1 from (*,G) and any (Si,G) “oilists”.2
2
S1
E1
To RP (10.1.5.1)
(Si, G) Traffic FlowShared TreeSPT Tree
A
B
P
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
152IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: SIncoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
PIM ASM Pruning - IOS Shared Tree Case
• B removes Ethernet1 from (*,G) and any (Si,G) “oilists”.2
• B’s (*,G) “oilist” now empty; triggers (*,G) Prune toward RP.3
(*,G) Prune3
S1
E1
To RP (10.1.5.1)
(Si, G) Traffic FlowShared TreeSPT Tree
A
B
P
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
153IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: S Incoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:43/00:02:11
PIM ASM Pruning - IOS Shared Tree Case
S1
E1
To RP (10.1.5.1)
(Si, G) Traffic FlowShared TreeSPT Tree
A
B
P
• A receives Prune; removes E0 from (*,G) “oilist”.(After the 3 second Multi-access Network Prune delay.)
4
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
154IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:02:13, RP 10.1.5.1, flags: SP Incoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
PIM ASM Pruning - IOS Shared Tree Case
S1
E1
To RP (10.1.5.1)
(Si, G) Traffic FlowShared TreeSPT Tree
A
B
• A receives Prune; removes E0 from (*,G) “oilist”.(After the 3 second Multi-access Network Prune delay.)
4
• A’s (*,G) “oilist” now empty; triggers (*,G) Prune toward RP.5
(*,G) Prune5
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
155IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Pruning - IOS Shared Tree Case
• Pruning continues back toward RP.6
6
S1
E1
To RP (10.1.5.1)
(Si, G) Traffic FlowShared TreeSPT Tree
A
B
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
156IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:43/00:02:11
(171.68.37.121, 224.1.1.1), 00:01:05/00:01:55, flags: TIncoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:05/00:02:55
State in A Before Pruning
PIM ASM Pruning - IOSSource (SPT) Case
S1
E1
Rcvr
To RP (10.1.5.1)To Source “Si”
B
Shared Tree
(Si, G) Traffic FlowSPT Tree
AS0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
157IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SCIncoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:43/00:02:11
(171.68.37.121, 224.1.1.1), 00:01:05/00:01:55, flags: CJT Incoming interface: Ethernet0, RPF nbr 10.1.2.1Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:05/00:02:55
State in B Before Pruning
PIM ASM Pruning - IOSSource (SPT) Case
S1
E1
Rcvr
To RP (10.1.5.1)To Source “Si”
(Si, G) Traffic FlowSPT Tree
A
B
Shared Tree
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
158IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SC Incoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:43/00:02:11
(171.68.37.121, 224.1.1.1), 00:01:05/00:01:55, flags: CJT Incoming interface: Ethernet0, RPF nbr 10.1.2.1Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:05/00:02:55
PIM ASM Pruning - IOSSource (SPT) Case
• B is a Leaf router. Last Rcvr leaves group G. 1
IGMP Leave1
S1
E1
Rcvr
To RP (10.1.5.1)To Source “Si”
A
B
Shared Tree
(Si, G) Traffic FlowSPT Tree
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
159IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SCIncoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:43/00:02:11
(171.68.37.121, 224.1.1.1), 00:01:05/00:01:55, flags: CJT Incoming interface: Ethernet0, RPF nbr 10.1.2.1Outgoing interface list:
Ethernet1, Forward/Sparse-Dense, 00:01:05/00:02:55
PIM ASM Pruning - IOSSource (SPT) Case
S1
E1
To RP (10.1.5.1)To Source “Si”
A
B
Shared Tree
(Si, G) Traffic FlowSPT Tree
• B removes Ethernet1 from (*,G) and all (S,G) OIL’s.2
2
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
P
160IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SCPIncoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
(171.68.37.121, 224.1.1.1), 00:01:05/00:01:55, flags: CJPT Incoming interface: Ethernet0, RPF nbr 10.1.2.1Outgoing interface list:
PIM ASM Pruning - IOSSource (SPT) Case
• B’s (*,G) OIL now empty; triggers (*,G) Prune toward RP.3
(*,G) Prune 3
S1
E1
To RP (10.1.5.1)To Source “Si”
B
AShared Tree
(Si, G) Traffic FlowSPT Tree
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
161IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: SCPIncoming interface: Ethernet0, RPF nbr 10.1.2.1,Outgoing interface list:
(171.68.37.121, 224.1.1.1), 00:01:05/00:01:55, flags: CJPT Incoming interface: Ethernet0, RPF nbr 10.1.2.1Outgoing interface list:
PIM ASM Pruning - IOSSource (SPT) Case
• B’s (S,G) OIL also now empty; triggers (S, G) Prune towards Si .4
(S,G) Prune 4
S1
E1
To RP (10.1.5.1)To Source “Si”
B
AShared Tree
(Si, G) Traffic FlowSPT Tree
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
162IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:01:43/00:00:00, RP 10.1.5.1, flags: S Incoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:43/00:02:11
(171.68.37.121, 224.1.1.1), 00:01:05/00:01:55, flags: T Incoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:01:05/00:02:55
PIM ASM Pruning - IOSSource (SPT) Case
• After A receives (*, G) Prune; removes E0 from (*,G) & (S,G) OIL’s(After the 3 second Multi-access Network Prune delay.)
5
5
S1
E1
To RP (10.1.5.1)To Source “Si”
B
AShared Tree
(Si, G) Traffic FlowSPT Tree
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
P
(171.68.37.121, 224.1.1.1), 00:01:05/00:01:55 flags: PT
163IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:02:32/00:00:00, RP 10.1.5.1, flags: SPIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
(171.68.37.121, 224.1.1.1), 00:01:56/00:00:53, flags: PTIncoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
PIM ASM Pruning - IOSSource (SPT) Case
• A’s (*,G) OIL now empty; triggers (*,G) Prune toward RP.6
(*,G) Prune6
S1
E1
To RP (10.1.5.1)To Source “Si”
A
B
Shared Tree
(Si, G) Traffic FlowSPT Tree
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
164IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:02:32/00:00:00, RP 10.1.5.1, flags: SPIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
(171.68.37.121, 224.1.1.1), 00:01:56/00:00:53, flags: PTIncoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
PIM ASM Pruning - IOSSource (SPT) Case
• A’s (S,G) OIL also now empty; triggers (S,G) Prune towards Si .7
(Si ,G) Prune7
S1
E1
To RP (10.1.5.1)To Source “Si”
A
B
(Si, G) Traffic FlowSPT Tree
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
165IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:02:32/00:00:00, RP 10.1.5.1, flags: SPIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
(171.68.37.121, 224.1.1.1), 00:01:56/00:00:53, flags: PTIncoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
PIM ASM Pruning - IOSSource (SPT) Case
S1
E1
To RP (10.1.5.1)To Source “Si”
A
B
• (Si,G) traffic ceases flowing down SPT.8
8
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
166IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:02:32/00:00:00, RP 10.1.5.1, flags: SPIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
(171.68.37.121, 224.1.1.1), 00:01:56/00:00:03, flags: PTIncoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
PIM ASM Pruning - IOSSource (SPT) Case
S1
E1
To RP (10.1.5.1)To Source “Si”
A
B
Not seeing any traffic, (Si,G) entry times out.
(171.68.37.121, 224.1.1.1), 00:01:56/00:00:02, flags: PTIncoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
(171.68.37.121, 224.1.1.1), 00:01:56/00:00:01, flags: PTIncoming interface: Serial1, RPF nbr 10.1.9.2Outgoing interface list:
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
167IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:02:32/00:02:59, RP 10.1.5.1, flags: SPIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
PIM ASM Pruning - IOSSource (SPT) Case
S1
E1
To RP (10.1.5.1)To Source “Si”
A
B
Now (*,G) starts its timer.
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
168IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:03:32/00:00:04, RP 10.1.5.1, flags: SPIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
PIM ASM Pruning - IOSSource (SPT) Case
S1
E1
To RP (10.1.5.1)To Source “Si”
A
B
After about 3 minutes . . .
(*, 224.1.1.1), 00:03:32/00:00:03, RP 10.1.5.1, flags: SPIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
(*, 224.1.1.1), 00:03:33/00:00:02, RP 10.1.5.1, flags: SPIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
(*, 224.1.1.1), 00:03:34/00:00:01, RP 10.1.5.1, flags: SPIncoming interface: Serial0, RPF nbr 10.1.4.1,Outgoing interface list:
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
169IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM ASM Pruning - IOSSource (SPT) Case
S1
E1
To RP (10.1.5.1)To Source “Si”
A
B
S0
E0 10.1.2.2
10.1.2.110.1.4.2
E0
After about 3 minutes . . . the (*,G) entry times out.
170IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir
171IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Bidirectional (BiDir) PIM Idea:
– Use the same tree for traffic from sources towards RP and from RP to receivers
Benefits:– Less state in routers
• Only (*, G) state is used• Source traffic follows the Shared Tree
– Flows up the Shared Tree to reach the RP– Flows down the Shared Tree to reach all other receivers
172IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Modifications for BiDir Operation All trees rooted at the RP
– Data traveling from source toward RP is moving UPSTREAM– Data traveling from RP toward receivers is moving DOWNSTREAM
Designated Forwarders (DF)– One DF per link
• Router with best path to the RP is elected DF
BiDir (*,G) forwarding rules:– DF is the only router that forwards packets traveling downstream onto the link– DF is the only router that picks-up upstream traveling packets off the link to forward towards
the RP
173IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
(*, 224.1.1.1), 00:00:04/00:00:00, RP 172.16.21.1, flags: BCBidir-Upstream: Ethernet0, RPF nbr 172.16.9.1Outgoing interface list:
Ethernet0, Bidir-Upstream/Sparse-Dense, 00:00:04/00:00:00Ethernet1, Forward/Sparse-Dense, 00:00:04/00:02:55
PIM Bidir Joining
RP
E F
A B CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
IGMP Join
D
Receiver 1 Joins Group Causing Router “D” to Create (*, G) State
174IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Joining
PIM (*,G) Join to DF
Router “D” Sends (*, G) Join to Router “F” (DF) Causing It to Create (*, G) State
RP
E
A B CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
D
(*, 224.1.1.1), 00:00:49/00:02:41, RP 172.16.21.1, flags: BBidir-Upstream: Ethernet0, RPF nbr 172.16.1.1Outgoing interface list:
Ethernet0, Bidir-Upstream/Sparse-Dense, 00:00:49/00:00:00Ethernet1, Forward/Sparse-Dense, 00:00:49/00:02:41
F
175IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Joining
PIM (*,G) Join to DF
Router “F” Sends (*, G) Join to “RP” Causing It to Create (*, G) State
E F
A B CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
D
(*, 224.1.1.1), 00:13:49/00:03:29, RP 172.16.21.1, flags: BBidir-Upstream: Null, RPF nbr 0.0.0.0Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:13:49/00:02:35
RP
176IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Joining
Branch of Shared Tree Is Now Built Down to Receiver 1
E
A B CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
RP
F
D
177IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Joining
Receiver 2
IGMP Join
Receiver 2 Also Joins Group
E
A B CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
RP
F
D
178IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Joining
Router “B” Creates (*, G) State
Receiver 2
E
A CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
RP
F
D
(*, 224.1.1.1), 00:00:04/00:00:00, RP 172.16.21.1, flags: BCBidir-Upstream: Ethernet0, RPF nbr 172.16.9.1Outgoing interface list:
Ethernet0, Bidir-Upstream/Sparse-Dense, 00:00:04/00:00:00Ethernet1, Forward/Sparse-Dense, 00:00:04/00:02:55
B
179IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Joining
Router “B” Sends (*, G) Join to “E” (DF) Causing It to Create (*, G) State
PIM (*,G) Join to DF
Receiver 2
A B CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
RP
D
F
(*, 224.1.1.1), 00:00:49/00:02:41, RP 172.16.21.1, flags: BBidir-Upstream: Ethernet0, RPF nbr 172.16.1.1Outgoing interface list:
Ethernet0, Bidir-Upstream/Sparse-Dense, 00:00:49/00:00:00Ethernet1, Forward/Sparse-Dense, 00:00:49/00:02:41
E
180IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Joining
PIM (*,G) Join to DF
Router “E” Sends (*, G) Join to “RP” (State on RP Remains Unchanged)
Receiver 2
E
A B CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
D
F(*, 224.1.1.1), 00:13:49/00:03:29, RP 172.16.21.1, flags: B
Bidir-Upstream: Null, RPF nbr 0.0.0.0Outgoing interface list:
Ethernet0, Forward/Sparse-Dense, 00:13:49/00:02:35
RP
181IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Joining
New Branch of Shared Tree Is Built to Receiver 2
Receiver 2
A CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
E
B
F
D
RP
182IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Sending
Source
Arriving Traffic from Source Causes Router “A” to Create (*, G) State
Receiver 2
CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
E
B
F
D
(*, 224.1.1.1), 00:32:20/00:02:59, RP 172.16.21.1, flags: BPBidir-Upstream: Ethernet0, RPF nbr 172.16.7.1Outgoing interface list:
Ethernet0, Bidir-Upstream/Sparse-Dense, 00:32:20/00:00:00
RP
A
183IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Sending
Traffic Is Forwarded Toward Router “E” and Also Arrives at IIF of Router “B”
Source Receiver 2
CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
E F
DA B
RP
184IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Sending
Router “B” Forwards Traffic Back Down Shared Tree ala Normal PIM-SM
Source Receiver 2
CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
RP
E F
DA
(*, 224.1.1.1), 00:00:04/00:00:00, RP 172.16.21.1, flags: BCBidir-Upstream: Ethernet0, RPF nbr 172.16.9.1Outgoing interface list:
Ethernet0, Bidir-Upstream/Sparse-Dense, 00:00:04/00:00:00Ethernet1, Forward/Sparse-Dense, 00:00:04/00:02:55
B
185IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Sending
Router “E” Forwards Traffic on Toward RP
Source Receiver 2
CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
F
DA B
(*, 224.1.1.1), 00:32:20/00:02:59, RP 172.16.21.1, flags: BPBidir-Upstream: Ethernet0, RPF nbr 172.16.7.1Outgoing interface list:
Ethernet0, Bidir-Upstream/Sparse-Dense, 00:32:20/00:00:00Ethernet1, Forward/Sparse-Dense, 00:00:04/00:02:55
E
RP
186IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Sending
Traffic Forwarded Toward RP also flows down existing branch to Rcvr 1
Source Receiver 2
CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
E
A B
F
D
RP
187IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir Sending
Question: Does the RP even have to physically exist?Source Receiver 2
CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
E
A B
F
D
RP
188IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Bidir RP
Answer: No. It can just be a phantom address.
Source Receiver 2
CE1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E1 (DF)
E0
E0 (DF)
Receiver 1
E
A B
F
D
RP
Question: Does the RP even have to physically exist?
189IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Recap: Common Multicast Flags - IOS S: Sparse Mode (in contrast to D for Dense Mode) s: SSM; only seen on (S,G) entries B: Bidir F: Register; set on First-Hop router P: Prune; entry has an empty OIL J: Join-SPT; (*,G) traffic exceeds SPT Threshold T: SPT; set on (S,G) entries after first (S,G) packet seen.
– Not applicable to SSM.
L: Local; router should receive and process this traffic C: Connected; the router has a directly connected receiver. I: Router Received Source Specific Host Report (SSM)
For YourReference
190IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
New PIM Model
For YourReference
191IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Old Model – IOS IPv4 (Simplified)
ADJ Table MET
MAC TableFIB TCAM
I/O Module
RouteProcessor
PIM MSDP
Mroute Table
IGMP
URIB
L2 Forwarding
Other HW
Hardware Drivers
IP FIB
L2 Forwarding Table
show ip mrouteshow ip mroute countshow ip igmp groupsshow ip msdp sa-cache
SA Cache
STP
Various hardware dependent show commands.
For YourReference
192IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM New Model – IOS-XR exampleshow pim group-mapshow pim topology [sh ip mroute]show igmp groupsshow igmp snooping <xxx>show msdp sa-cache
show mrib route [sh ip mroute]
show mfib route [sh ip mroute]show mfib connectionsshow mfib counter
show mfib hardware route olist loc <>show mfib hardware connection loc <>show mfib hardware ltrace loc <>show mfib hardware interface loc <>
show controller np counters allshow controller np struct <id> allshow controller np summary all NP
PRM/uIDBNETIO
Line Card
SupervisorEngine
MSDP PIM
MRIB
IGMP
URIB
STP
MFIB
MFIB PI
MGID Server
MFIB PD
PIM Topology
HardwareDependent
L2FIB
L2FIB
Fabric
For YourReference
193IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM New Model – NX-OS example
show ip pim topology [sh ip mroute]show ip pim route [sh ip mroute]show ip igmp route show ip igmp snooping groupsshow ip msdp route
show routing ip multicast [sh ip mroute]
show forwarding distribution ip multicast routeshow forwarding distribution ip igmp snooping
show forwarding ip multicast route
show system internal forwarding ip multicast routeshow system internal ip igmp snooping
ADJ Table MET
MAC TableFIB TCAM
I/O Module
SupervisorEngine
MSDP PIM
MRIB
IGMP
URIB
STP
MFDM
PIXMC
PIXM
IP FIB
Other HW
Hardware Drivers
L2MCAST
PIM Topology
HardwareDependent
For YourReference
194IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Topology Table Example – XR
RP/0/5/CPU0:rtr#sh pim topology 225.1.1.1
Fri Sep 16 12:49:18.533 CESTIP PIM Multicast Topology TableEntry state: (*/S,G)[RPT/SPT] Protocol Uptime InfoEntry flags: KAT - Keep Alive Timer, AA - Assume Alive, PA - Probe AliveRA - Really Alive, IA - Inherit Alive, LH - Last HopDSS - Don't Signal Sources, RR - Register ReceivedSR - Sending Registers, E - MSDP External, EX - ExtranetDCC - Don't Check Connected, ME - MDT Encap, MD - MDT DecapMT - Crossed Data MDT threshold, MA - Data MDT group assignedInterface state: Name, Uptime, Fwd, InfoInterface flags: LI - Local Interest, LD - Local Dissinterest,II - Internal Interest, ID - Internal Dissinterest,LH - Last Hop, AS - Assert, AB - Admin Boundary, EX – Extranet
(*,225.1.1.1) SM Up: 5w2d RP: 192.168.0.3*JP: Join(never) RPF: Decapstunnel1,192.168.0.3 Flags:GigabitEthernet0/0/0/0 5w2d fwd Join(00:03:20)
(192.168.1.18,225.1.1.1)RPT SM Up: 00:00:09 RP: 192.168.0.3*JP: Prune(never) RPF: Decapstunnel1,192.168.0.3 Flags: KAT(00:03:21) RA DCC RR (00:04:22)GigabitEthernet0/0/0/0 00:00:09 off Prune(00:03:20)
(192.168.1.18,225.1.1.1) SM Up: 00:07:51JP: Null(never) RPF: GigabitEthernet0/0/0/1,192.168.1.5 Flags: KAT(00:03:21) RA DCC RR (00:04:22)No interfaces in immediate olist
For YourReference
195IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM Topology Table Entry Flags/TimersEntry Flags
Flag/Timer Name Description
KAT() Keep-Alive Timer Countdown timer. If goes to zero, entry is removed.Join() Join Timer Countdown timer. Time until a PIM Join is sent upstream.
Prune() Prune Timer Countdown timer. Time until a PIM Prune is sent upstream.AA Assume Alive Only set after the route has been alive once.PA Probe Alive Check to see if any traffic is flowing for this route.RA Really Alive PIM sets this flag when it has been signaled that the route has seen traffic.IA Inherit Alive Inherit Alive Interfaces from Parent routeLH Last Hop Last Hop Router. A directly connected host has joined via IGMP/MLD on one of the Entry's Interfaces.
DSS Don't Signal Sources PIM doesn't want to be signaled when MFIB hears new sources on Shared Tree.RR Register Received PIM Register Messages are being ReceivedSR Sending Registers PIM Register Messages are being SentE MSDP External (S,G) learned from MSDP Peer
DCC Don't Check Connected Don't check for directly connected Sources
Interface FlagsFlag/Timer Name Description
Join() Join Timer Countdown timer. Time until Interface Join Times OutPrune() Prune Timer Countdown timer. Time until Interface Prune Times Out
LI Local Interest Received IGMP/MLD report/join for group ("C" flag in IOS)LD Local Disinterest Received IGMP/MLD exclude (S,G)II Internal Interest Router CPU IGMP/MLD include join ("L" flag in IOS)ID Internal Disinterest Router CPU IGMP/MLD exclude (S,G)LH Last Hop Last Hop Router. A directly connected host has joined via IGMP/MLD on this Interface.AS Assert A PIM Assert has been seen on this InterfaceAB Admin Boundary Interface would be in olist but it is blocked by Admin Boundary.
For YourReference
196IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
PIM MRIB State Example – XR
RP/0/5/CPU0:rtr#show mrib route
IP Multicast Routing Information BaseEntry flags: L - Domain-Local Source, E - External Source to the Domain,
C - Directly-Connected Check, S - Signal, IA - Inherit Accept,IF - Inherit From, D - Drop, MA - MDT Address, ME - MDT Encap,MD - MDT Decap, MT - MDT Threshold Crossed, MH - MDT interface handleCD - Conditional Decap, MPLS - MPLS Decap, MF - MPLS Encap, EX - Extranet
Interface flags: F - Forward, A - Accept, IC - Internal Copy,NS - Negate Signal, DP - Don't Preserve, SP - Signal Present,II - Internal Interest, ID - Internal Disinterest, LI - Local Interest,LD - Local Disinterest, DI - Decapsulation InterfaceEI - Encapsulation Interface, MI - MDT Interface, LVIF - MPLS Encap,EX - Extranet
(*,225.0.0.0) RPF nbr: 0.0.0.0 Flags: CUp: 00:02:13Outgoing Interface List
GigabitEthernet0/2/1/0.102 Flags: F NS, Up: 00:02:13
(192.2.1.2,225.0.0.0) RPF nbr: 192.2.1.2 Flags:Up: 00:00:07Incoming Interface List
GigabitEthernet0/2/1/1 Flags: A, Up: 00:00:07Outgoing Interface List
GigabitEthernet0/2/1/0.102 Flags: F NS, Up: 00:00:07
For YourReference
197IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
MRIB Entry FlagsEntry Flags
Flag/Timers Name Description
UP Entry Up Timer Time Entry has existedC Directly-Connected Check Perform check on incoming packets applicable to this Entry.S Signal Signal PIM.IA Inherit Alive Inherit Alive Interfaces from Parent routeIF Inherit FromD Drop
MA MDT Address MVPN MDT Tunnel Address (Multicast Address)ME MDT Encapsulate Encapsulate in MDT TunnelMD MDT Decapsulate Decapsulate from MDT TunnelMT Crossed Data MDT Threshold (S,G) traffic has crossed Data MDT Threshold.MH MDT interface handle Interface used for MVPN MDT Tunnel
Interface FlagsFlag/Timers Name Description
UP Interface Up Timer Time Interface has existed in Outgoing Interface ListF Forward Forward multicast packets on this interfaceA Accept Accept multicast packets on this interfaceIC Internal CopyNS Negate Signal Invert Signal status of Entry for this interface. (Often means "Signal".)DP Don't PreserveSP Signal Present MFIB is Signaling PIM. Typically for packet arriving on interface.II Internal Interest Router CPU IGMP/MLD include join ("L" flag in IOS)ID Internal Disinterest Router CPU IGMP/MLD exclude (S,G)LI Local Interest Received IGMP/MLD report/join for group ("C" flag in IOS)LD Local Disinterest Received IGMP/MLD exclude (S,G)DI Decapsulation Interface PIM Registers received on this interface. (Typically the DecapTunnel.)EI Encapsulation Interface PIM Registers sent on this interface. (Typically the EncapTunnel.)
For YourReference
198IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
• White Papers
• Web and Mailers
• Cisco Press
More Information
RTFB = “Read the Fine Book”
199IP Multicast Survival Guide II - 2nd Edition-rev6.pptx
Multicast Bedtime Stories