november 201079 th ietf @ beijing, china1 cross stratum optimization (cso) bar bof

November 2010 79th IETF @ Beijing, China 1

Cross Stratum Optimization (CSO) Bar BOF


Agenda

• IETF CSO Effort Background (Young Lee, 5 min)• NA-ARAM (Ning So, 15 min)• NS Query (Young Lee, 15 min)• Q & A (25 min)


IETF CSO Effort• CLO Bar BOF was held in Maastricht IETF meeting (78th)

– 40 + attendants from carriers, vendors, academia and research institutes

• Created IETF mailing list: [email protected] • Public Archive: http://www.ietf.org/mail-archive/web/cso• CLO -> CSO (Name changes) • CSO := {NS Query, NA-ARAM}

Where NS Query = Network Stratum QueryNA-ARAM = Network Aware Application Resource Assignment and Mobility

• NS Query BOF Request didn’t go through the initial IESG approval– Need more clarification

mailto:[email protected]

http://www.ietf.org/mail-archive/web/cso


Network Aware Application Resource Assignment and Mobility in Data Centers

draft-so-network-aware-application-problem-01.txt

Ning So (UTD) Young Lee (Huawei) Dave McDysan (Verizon) Greg Bernstein (Grotto)Tae Yeon Kim (ETRI) Kohei Shiomoto (NTT)Oscar Gonzalez de Dios (Telefonica)


Problem Description• Many application services offered by Data Center

make significant use of the underlying networks resources

• The same application service can be offered by multiple geographically dispersed data centers. – allowing the application to be closer to the end-users to

enhance service performance and user experience • Problem #1: The decision as which server/data

center to select for an application request from end-users can negatively affect the quality of experience (QoE) of the users if not done correctly.


Problem Description (Cont’d)• VMs supporting the applications can be actively

distributed within and/or between data centers. – Improve server utilization– Prevent service performance degradation during the peak

usage time period, and during equipment failures. • Problem #2: When instantiating new VMs or

migrating existing VMs across data centers, the underlying network loading conditions within a data center (LAN) or between data centers (MAN/WAN) need to be considered


Exemplary Cloud Data Center

End-User 1

1 2

3

CE 1

CE 2

12

PE 1

PE 2

PE 4

PE 3

PE

1 2

CE 3

ApplicationServers

CE 4

AccessNetwork Carrier

BackboneNetwork

DC 1

DC 2

DC 3AccessNetwork

PE

CE 4End-User 2

Global Load Balancer


Current Server Selection Technology

• The server selection for an application/VM is done by load-balancer. – The load balancer is aware of a certain level of

server usage data and distributes the application requests based on that data.


Deficiencies of Current Server Selection Technology

• The current load balancing technology is insufficient in providing an optimal decision across multiple VLANs and multiple Data Centers – No standard solution for the communication exchange among load

balancers located in different Data Centers • load balancers from different vendors cannot communicate to each other

– load balancers know little about the underlying network conditions• When migrating existing VMs/applications from one data center to

another, the underlying network load condition in LAN/MAN/WAN can be constraining factors.

– Load balancers know little about user condition


Optimized Server Selection Criteria

• Factors need be considered in choosing the right server in the right data center for an application request or in instantiating new or migrating existing VMs/applications– Server level load condition in a data center– Intra data center network condition – Carrier MAN/WAN network condition – User Condition


Server Selection Criteria Details• Server level load condition

– VM supportability limitations – CPU utilization– Memory segmentation and consumption– Application limitations e.g. max # of simultaneous instances of the application

supportable– Storage access speed (disk, RAM, etc.)– Environment considerations such as server temperature, power load, and

electrical cost at the time– Operational and managerial considerations such as location of peer servers

and storages– VM to NIC switching in a virtual switch

• Intra-DC network condition – Server NIC to Top of Rack (ToR) Switch– TOR switch to Layer 2 Switch - link and node level– Between L2 Switches and L2 switch to L2 core/gateway switch/router - link

and node level– L2 gateway router to provider edge (PE) router - link and node level.


Server Selection Criteria Details• Carrier MAN/WAN network condition

– Type of networks and the technical capabilities of the networks– Bandwidth capabilities and availability – Latency– Jitter– packet loss– other Network Performance Objective (NPO) as defined in section 5 of

[ITU-T Y.1541] • User condition

– User access capabilities and limitations (e.g., user terminal information such as codec for video application)

– User location– Optional user preferences (for some application, user may be able to

specify its preferences. For example, the preferred server location for gaming).


Requirements for Optimized NA-ARAM• End-users send requests to the Application Controller (global load

balancer), which makes server assignment decision for the user application.

– End-users may send the following• Required application: this may be a simple URL request • Specific server identity or location. • Additional security requirements• Modified application specs. (for mobile users) • Optional end-user terminal information

• Inter DC communication: the application controller need to be aware – Server/Application Status from each of the Data Centers where the

application servers are located – Intra-DC network conditions from each of the Data Centers where the

application servers are located• Data Center-Network Stratum Communication

– The details of how this can be accomplished are addressed in Network Stratum Query draft.


Thanksand

Questions?


NQ Query

draft-lee-network-stratum-query-problem-01.txt

Young Lee (Huawei) Dave McDysan (Verizon)Ning So (UTD) Greg Bernstein (Grotto)Tae Yeon Kim (ETRI) Kohei Shiomoto (NTT)Oscar Gonzalez de Dios (Telefonica)


Backgrounds• Most Internet Services are offered by the “servers”

geographically spread. • Data Centers Networks have emerged as physical

infrastructure for Content Delivery Networks and Cloud Computing.

• Application services, e.g., data centers, make significant use of the underlying network services

• Application services have access to little or no information about network services, e.g., available bandwidth, congestion level, etc.


Context of NS Query:Data Center Networks (DCN)

End-User 1

GLB 1 2

3

GR

GR

12

PE 1

PE 2

PE 4

PE 3

PEGLB

1 2

GR

GLB

ApplicationResource(server)

CE 4

AccessNetwork Carrier

BackboneNetwork

DC 1

DC 2

DC 3

(3) Inter DC Communication(exchange server performance data)

(1) End-user to DC communication(request/reply)

(4) DC-Carrier Communication(NS Query)

AccessNetwork

PE

CE 4

End-User 2

(2) Intra DC Communication

Direct Access(Corporate User)

CE 4


Cross-Stratum Application Stratum• Distributed Resources: Data Centers

with servers, content, data sets, computing power, cache/mirror

• Uses Network Resources• Different QoS requirements for each

application

Network Stratum• Bandwidth, Connections, Links, • Connection Processing (Creation,

Deletion, Management)• Admission Control, Resource Reservation • Applications uses resources in IP, MPLS,

and/or Optical Transport Networks, Layer 2

Network Stratum

Application Stratum

NS Query


Application Service ProfilesCharacteristics & QoS Requirement of application service from a

network perspective:• Location profile: locations of both the clients and the sources• QoS profile: (i) Delay Tolerance Bound; (ii) Jitter Tolerance Bound; (iii) Packet Delivery Ratio

Tolerance; (iv) Network Availability, etc.• Connectivity profile: (i) P-P; (ii) P-MP; (iii) MP-MP; (iv) Any Cast• Directionality profile: (i) uni-directional; (ii) bi-directional• Bandwidth profile: Maximum, average, and minimum bandwidth requirements for the connectivity,

maximum burst rate, maximum burst duration, etc.• Duration of service profile: service time of the application• Network media profile: (i) optical only; (ii) no microwave, etc.• Restoration profile: (i) Reroute required; (ii) do not re-route, etc. • Security profile: (i) dedicated end-to-end VPN-like resource allocation; (ii) dedicated physical

resource allocation

Currently, network is not informed of the nature of the application --- there is no good way to convey the application service profile to network stratum


Carrier MAN/WAN network condition

• Type of networks and the technical capabilities of the networks;

• Bandwidth capabilities and availability;• latency;• jitter; • packet loss;• And other Network Performance Objective

(NPO) as defined in section 5 of [ITU-T Y.1541].


CSO NS Query ArchitectureGlobalLoad

Balancer

ApplicationControl

Gateway

Inter DCGateway

Intra DCResource

RemoteData Centers

Interfaces

End-UserInterfaces

NetworkControl

Gateway

NS Query (First Step)

IPPM

TED

LSDBBGP-RIBIGP-RIB

NS Query (Second Step)


Two-stage Query• A Vertical Query

– First Stage: A vertical query from an application entity (i.e., the Application Control Gateway (ACG) in Data Center) to an entity representing the network (i.e., the Network Control Gateway (NCG)) for highly summarized and abstracted network related information for a particular point in network; and

• A Horizontal Query– Second Stage: Internal "horizontal query" at the network layer along with

summarization and abstraction of the network information in a form that preserves network confidentiality and significantly reduces the amount of information that needs to be transferred.

– The raw information needed to perform this summarization/abstraction is defined in existing and emerging network management standards and protocols (SNMP, Netflow, sFlow, IPPM, IGP, RIB, etc...).

– NS Query would not necessarily standardize how this "internal horizontal queries" and summarization would be performed but would illustrate how such processes can be accomplished via standards, emerging standards or common commercial practices.


NS Query Example• For a particular point in networks, the NS Query can ask the

following network load data in a summarized/abstract form:– b/w availability (this case the minimum b/w requirement should be

provided) – latency – jitter – packet loss

• Note that this can be asked in a different way. For example, the query can simply ask: – Can you give me if you can route x amount of b/w (from server to

end-user) within y ms of latency? – Can you give me if you can route x amount of b/w (from server to

end-user) with no packet loss?


Thanks!

november 201079 th ietf @ beijing, china1 cross stratum optimization (cso) bar bof

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