lisp-ddt · lisp review – why do this? initially, to try to find a way to scale the routing...
Post on 24-Mar-2020
3 Views
Preview:
TRANSCRIPT
1
LISP-DDT Vince Fuller, Cisco
Glen Wiley. Verisign
NANOG-55 Vancouver, BC
2
Agenda Review of LISP: concepts and network elements
The LISP mapping database today
Description of LISP-DDT
Development and deployment status
Future direction
3
LISP Review – why do this? Initially, to try to find a way to scale the routing system
– IAB Routing and Address Workshop, October 2006, RFC 4984
– Separation of ID and location in IP addresses
– LISP started during workshop, others have followed
LISP-like indirection turns out to be useful for other things: – multi-homing with ingress traffic engineering
– mobility
– network virtualization
– large-scale VPNs
– ipv6 transition
4
LISP Review – why do this?
5
LISP Review – EIDs and RLOCs
Endpoint IDs (EIDs) are used by hosts – assigned to “sites”, portable like “PI” space
– not propagated by the global routing system
Routing Locators (RLOCs) are used by the routing system – assigned to sites according to topology, like “PA” space
– aggregated for use by the global routing system
User data is LISP-encapsulated – RLOC source and destination in outer header
– Source EID is “mapped” to RLOC by edge device
– Mapping system consulted to find RLOC(s) for destination EID
6
LISP Review – network elements Ingress Tunnel Router (ITR) at LISP site
– encapsulates user data in LISP datagram
Egress Tunnel Router (ETR) at LISP site – decapsulates LISP datagram, delivers user data
ETR/ITR functions typically co-located in one device (“xTR”)
Proxy Ingress Tunnel Router (PITR), infrastructure – acts as ITR for non-LISP traffic (“legacy” Internet sources)
Proxy Egress Tunnel Router (PETR), infrastructure – acts as ETR for non-LISP traffic (“hop over” non-LISP routers)
7
S1
S2
ITR
ITR
D1
D2
ETR
ETR
S D
Provider A 10.0.0.0/8
Provider B 11.0.0.0/8
Provider X 12.0.0.0/8
Provider Y 13.0.0.0/8
LISP Site LISP Site
10.0.0.1
11.0.0.1 13.0.0.2
12.0.0.2
PI EID-prefix 2.0.0.0/24
PI EID-prefix 3.0.0.0/24
This policy controlled by destination site
Legend: EIDs -> Green Locators -> Red Physical link
DNS entry: D.abc.com A 3.0.0.3
1
EID-prefix: 3.0.0.0/24 Locator-set:
12.0.0.2, priority: 1, weight: 50 (D1) 13.0.0.2, priority: 1, weight: 50 (D2)
Mapping Entry
3
LISP Data Plane Unicast Packet Forwarding
2.0.0.2 -> 3.0.0.3
2
2.0.0.2 -> 3.0.0.3 11.0.0.1 -> 12.0.0.2
4
5
6
2.0.0.2 -> 3.0.0.3 11.0.0.1 -> 12.0.0.2
7
2.0.0.2 -> 3.0.0.3
8
8
LISP Review - Mapping Database
EID-to-RLOC Mappings – Originated by LISP site ETRs
– ITR sends Map-Request to ETR (via MR/MS) to obtain mapping
– Mapping Database enables an ITR to find the ETR(s) for an EID
Must Support Millions of Sites, Changes – Rapid response to connectivity changes
– Less so for subscription-time database changes
Prototyped LISP+ALT Using BGP+GRE+VRF – Was conceptually simple, operationally complex in practice
– Lacked flexibility for adding EID types, instance IDs, etc.
9
LISP Review – Database Infrastructure Map Server (MS) – publishes EID-prefixes in database
– ETR registers to one or more Map Servers
– A Map Server publishes EID-prefixes so an ITR can find them
Map Resolver (MR) – index for EID to ETR – accepts Map-Request from ITR, finds correct ETR(s)
LISP+ALT – overlay network between MR and MS – tunnels and BGP sessions between MR, MS, and ALT routers
– ALT routers are intermediate nodes that provide EID aggregation
– Map-Request, not user data, is forwarded through the ALT to MS
– ETR receives Map-Request from MS and sends Map-Reply to ITR
– ALT is being replaced by DDT
10
S1
S2
ITR
ITR
D1
D2
ETR
ETR
S D
Provider A 10.0.0.0/8
Provider B 11.0.0.0/8
Provider X 12.0.0.0/8
Provider Y 13.0.0.0/8
MR
ALT
MS
ALT
ALT ALT
LISP Site LISP Site
PI EID-prefix 3.0.0.0/24
PI EID-prefix 2.0.0.0/24
10.0.0.1
11.0.0.1 13.0.0.2
12.0.0.2
65.1.1.1 66.2.2.2
Legend: EIDs -> Green Locators -> Red BGP-over-GRE Physical link
DNS entry: D.abc.com A 3.0.0.3
2.0.0.2 -> 3.0.0.3 How do I get to 3.0.0.3?
11.0.0.1 -> 3.0.0.3 Map-Request
(udp 4342) nonce
11.0.0.1 -> 65.1.1.1 LISP ECM (udp 4342)
[1]
[2] [3] [4]
11.0.0.1 -> 3.0.0.3 Map-Request
(udp 4342) nonce 11.0.0.1 -> 3.0.0.3
Map-Request (udp 4342)
nonce
66.2.2.2 -> 12.0.0.2 LISP ECM (udp 4342) [5]
LISP Control Plane – MR/MS with ALT Map Request uses BGP/GRE overlay from MR to MS
11
What is LISP-DDT?
LISP Delegated Database Tree – Hierarchy for Instance IDs and for EID Prefixes
– Statically Configured
– Delegations are signed (public-key) and verified when used
Conceptually, similar to DNS (IN-ADDR hierarchy) – but different prefix encoding, messages, etc.
– we did try using DNS protocol directly, but…
• prefix encoding was painful/ugly
• negative map replies were problematic
• couldn’t do it right without protocol modifications
12
DDT Node Statically configured
Authoritative prefix – IID and EID/length for which DDT node is responsible
– root nodes have IID=any, EID=0/0
Delegations – sub-prefixes delegated to “child” DDT nodes (or Map Servers)
Accepts DDT Map-Request, returns Map-Referral message – contains pointer to node with more-specific information
• NODE-REFERRAL for another DDT Node
• MS-REFERRAL for a DDT Map Server
– “negative” action codes also possible (more on those later)
13
DDT Map Server DDT Node may also be a DDT Map Server
– accepts ETR registrations (just like any other Map Server)
– forwards Map-Request to ETR
– can return proxy Map-Reply (if configured to do so)
– LISP-SEC authentication sent only following MS-REFERRAL
– MS-ACK returned when EID fully resolved
– “negative” action codes described later
14
DDT Map Resolver DDT Map Resolver finds RLOC for authoritative Map Server
– Cache Map Request from ITR
– Query the DDT hierarchy iteratively with DDT Map-Requests
– Detect Loops/Delegation Errors
– Follow referrals to find the right DDT Map-Server for an EID
DDT Map Resolvers thus have state: – Referral Cache
– Map-Request Queue
– Key differences from “ordinary” Map Resolvers
15
Referrals & Their Actions ‘Positive’ referral is a pointer to a DDT node(s) with
information about a (usually) more-specific EID-Prefix Type 0, NODE-REFERRAL
Type 1, MS-REFERRAL
Type 2, MS-ACK
DDT MR uses this information to contact the next DDT node/MS
‘Negative’ referrals are used to indicate other actions: Type 3, MS-NOT-REGISTERED
Type 4, DELEGATION-HOLE
Type 5, NOT-AUTHORITATIVE
Referral includes public-key signature by delegator
16
DDT Node 1 Root 0.0.0.0/0 IID=0
DDT Node 2 10.0.0.0/8 IID=0
DDT Node 3 10.1.0.0/16 IID=0
MS1 DDT-Node 4 10.1.0.0/24 IID=0
Setup & Configuration
MR
Map Request
Map Referral
Static Delegation Hierarchy
Map Reply
ETR 10.1.0.0/24
ETR-MS Registration
Configura)on and Setup
1
1) MR configured with Root (DDT Node 1) RLOC
3
3) ETR is registering its EID to the Leaf MS 2
2) DDT-1, DDT2, DDT-3, DDT/MS-4 configured children with child prefixes, and authoritative prefixes
Ex. DDT-2 Delegates child 10.1.0.0/16 to MS3 DDT-2 configured authoritative for 10/8 in IID0
17
DDT Node 1 Root 0.0.0.0/0
DDT Node 2 10.0.0.0/8
DDT Node 3 10.1.0.0/16
DDT Node-4 MS1 10.1.0.0/24
Map Request, Referral, & Reply
MR
ITR
Map Request
Map Referral
Static Delegation Hierarchy
Map Reply
ETR-MS Registration
ETR 10.1.0.0/24
First Request Packet Flow
1
1) ITR sends MRQ to MR via ECM
2
2) MR sends Iterative-MRQ to its statically configured Root DDT-Node via ECM-Like-packet
3 3) Root Sends a Map Referral to MR informing
the MR who is the next DDT-Node (2) to try
4
4) MR repeats steps 2 & 3 until it gets to leaf MS1 (DDT-Node-4) which has the EID registered (or an error indication)
5
5) MS1 (DDT-4) sends Map-Referral to MR with action code MS-ACK
7
7) ETR sends Map-Reply to the ITR
6
6) MS1 (DDT-4) receives, processes MR and fwd to ETR
18
DDT-1 0.0.0.0/0
DDT-2 10.0.0.0/8
DDT-3 10.1.0.0/16
DDT-4 MS1 10.1.0.0/24
Once MR’s Referal-Cache is Populated
1) MRQ in ECM arrives on MR 2) MR sends MRQ in ECM (possibly double
encaped if lisp-sec is used to secure referal path) to Cached Map-Server MS1 (DDT-4)
3) MS1 decaps ECM and then sends Map-Request in new ECM to ETR MS1 also sends a Map-Referal ACK back to MR
4) ETR sends Map-Reply to ITR
MR
ITR
Map Request
Map Referral
Static Delegation Hierarchy
Map Reply
ETR 10.1.0.0/24
ETR-MS Registration
Steady State
1
2
3
4
19
Implementation Status
IOS and NXOS implementations complete
OpenLISP implementation nearly complete
Verisign implementation in progress
Development and interoperability testing going on now
Configuration is pretty simple – much easier to configure and operate than LISP+ALT!
Does not include proposed DDT-SEC extensions
20
Organization and Operational Status
Collaboration among Cisco, Verisign, Intouch NV – discussions with others, more welcome
Common root: ddt-root.org
Running on LISP pilot network – transition from LISP+ALT in March, 2012
– ALT configurations removed in April, 2012
Looking at various options for organizational structure – emphasis on transparency, scalability, efficiency, simplicity
21 Static Delegation Hierarchy
DDT Beta (IID0) Network Deployment
Cisco’s DDT Roots: (Iota-Root) IID: * EID: * arin-ddt.rloc.lisp4.net ripe-ddt.rloc.lisp4.net vxnet-ddt.rloc.lisp4.net
MR/MS: EID Aggregates: 153.16.0.0/19 2610:D0:1000::/36 2610:D0:FACE::/48 153.16.21.0/24 TO MN 153.16.22.0/24 TO MN isc-mr-ms asp-mr-ms cisco-sjc-mr-ms1 eqx-ash-mr-ms
Other DDT Roots IID * EID: * sigma.ddt-root.org (Verisign) mu.ddt-root.org
ARIN-Region
RIPE- Region AP-Region LACNIC-Region
Mobile Node Region
MR/MS: EID Aggregates: 153.16.32.0/19 2610:D0:2000::/36 l3-london-mr-ms tdc-mr-ms intouch-ams-mr-ms intouch-ams-mr-ms
MR/MS: EID Aggregates:153.16.64.0/19 2610:D0:3000::/36 apnic-mr-ms
DDT Node with ‘child referrals’
MR/MS’s 153.16.21/24 153.16.22/24 2610:d0:1219::/48 2610:d0:120e::/48 asp-isis isc-isis intouch-isis
MR/MS: EID Aggregates:153.16.128.0/19 2610:D0:5000::/36 lacnic-mr-ms
asp-isis
DDT Beta- Network TLDs IID 0 v4-EID: 153.16.0.0/16 v6-EID: 2610:D0/32 uninett-ddt.rloc.lisp4.net sj-ddt.rloc.lisp4.net msn-ddt.rloc.lisp4.net
Beta Network DDT TLD
Iota- root Servers
22
LISP Development at Verisign Verisign has operationalized a global public LISP
mapping database system Support OpenLISP development Multiple phases for Verisign LISP rollout
- Pilot program to provide a secure and reliable EID to RLOC Mapping Service (LISP-DDT currently)
- Currently testing Customer Portal used for provisioning and managing external customers
- In-house developed LISP service using the same infrastructure currently in place to support COM/NET DNS (Q4 2012)
23
LISP Footprint at Verisign LISP Pilot Network - Redundant Servers & Resolvers at each site - Redundant Transit from each site - Supports both IPv4 and IPv6
Vendor Diverse Software Deployed - Dell R710s running NX-OS - Dell R710s running OpenLISP (June ’12) - Dell R710s running Verisign Mapping Servers/Resolvers (Q4 ‘12)
Root Servers Deployed at multiple Datacenters - Dell R710s running NX-OS - Root IPs:
- 72.13.36.141 - 69.58.178.141
- Efforts within our Labs, Engineering organizations in cooperation with Cisco for some time now
24
LISP on Verisign Infrastructure Process approximately 60+ billion DNS queries daily
100% network uptime more than a decade
70+ Global Points of Presence 4500+ computing devices
The World Trusts Verisign to Operate the Internet’s Critical Infrastructure
Manages ~105 million+ domain names
25
Specification & Standardization
Individual Submission in IETF LISP WG – draft-fuller-lisp-ddt-01.txt
Work In Progress, -02 draft will be out soon – better integration of action code descriptions – additional work needed on security extensions
– finite state machine for pending request processing
Consistent With WG Charter – planned adoption as WG draft
– expected replacement for LISP+ALT
26
Future Work
LISP Mapping Provider “eco-system”(?)
Internet-Scale Deployment(?)
27
LISP Resources
www.lisp4.net – background information, pointers to other presentations
– pilot network topology, traffic, etc. – LISP Network Operators Group (LNOG)
lisp.cisco.com – Cisco implementation info, image downloads, etc.
lisp@ietf.org - IETF LISP working group – https://datatracker.ietf.org/wg/lisp
– “core” documents scheduled for RFC publication “RSN”
LISP-DDT route operation - http://ddt-root.org
28
Questions and Comments?
Contacts: lisp-support@cisco.com
lisp@verisign.com
lisp-interest@cisco.com
(especially if you’re interested in participating )
top related