IEEE 802 Tutorial Congestion Notification

Patricia Thaler

Description

IEEE 802 Tutorial:Congestion Notification17 July 2006San Diego, CA¾¾¾¾¾¾¾¾¾¾AgendaOverviewPresenter: Pat Thaler; BroadcomChair IEEE 802.1 Congestion management subgroupMarketPresenter: Manoj Wadekar; IntelExample mechanism description and simulationDavide Bergamasco; CiscoDocument structurePresenter: Norm Finn; CiscoSummary and questionsPresenter: Pat ThalerOverviewPat Thaler¾¾¾¾Congestion NotificationCongestion NotificationCongestion Notification (CN) provides a means for a bridge to notify a source of congestion allowing the source to reduce the flow rate.CN is targeted at networks with low bandwidth delay products: e.g. data center and backplane networks Benefits: avoid frame loss; reduce latency; improve performanceAmendment to IEEE Std 802.1Q¾¾¾¾¾¾PAR scope*Specify protocols, procedures and managed objects for Congestion management oflong-lived data flowsIn network domains of limited bandwidth delay productBridges signal congestion to end stationsVLAN tag priority value segregates congestion controlled traffic Allows simultaneous support of congestion controlled and non-controlled domainsPAR scope, purpose and need are summarized on these slides. For full text see backup slides¾¾¾¾¾PAR purposeData center network and backplane fabrics that with applications that depend onLower latencyLower probability of packet lossAllowing these applications to share the network with traditional LAN ...

Informations

• Publié par: Utto
• Nombre de lectures: 77
• Langue: English

Extrait

IEEE 802 Tutorial: Congestion Notification

17 July 2006

San Diego, CA

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¾ ¾ ¾ ¾

Agenda

Overview ¾Presenter: Pat Thaler; Broadcom Chair IEEE 802.1 Congestion management subgroup Market ¾Presenter: Manoj Wadekar; Intel Example mechanism description and simulation ¾Davide Bergamasco; Cisco Document structure ¾Presenter: Norm Finn; Cisco Summary and questions ¾Presenter: Pat Thaler

Overview

Pat Thaler

Congestion Notification

¾Congestion Notification (CN) provides a means for a bridge to notify a source of congestion allowing the source to reduce the flow rate.

¾CN is targeted at networks with low bandwidth delay products: e.g. data center and backplane networks

¾Benefits: avoid frame loss; reduce latency; improve performance

¾Amendment to IEEE Std 802.1Q

PAR scope*

¾Specify protocols, procedures and managed objects for Congestion management of ¾long-lived data flows ¾In network domains of limited bandwidth delay product ¾Bridges signal congestion to end stations ¾VLAN tag priority value segregates congestion controlled traffic ¾Allows simultaneous support of congestion controlled and non-controlled domains

PAR scope, purpose and need are summarized on these slides. For full text see backup slides

PAR purpose

¾Data center network and backplane fabrics that

¾with applications that depend on ¾Lower latency ¾Lower probability of packet loss

¾Allowing these applications to share the network with traditional LAN applications

PAR Need

¾Opportunity for Ethernet as a consolidated Layer 2 solution in high-speed, short-range networks to support ¾Traffic that uses specialized layer 2 networks today: ¾data centers, ¾backplane fabrics, ¾single and multi-chassis interconnects, ¾computing clusters, ¾storage networks. ¾Network consolidation to provide operational and equipment cost benefits

Market Requirements

Manoj Wadekar

12,000,000 10,000,000 8,000,000 6,000,000 4,000,000 2,000,000 0

Source: IDC, 2005

Datacenter : Blade Servers

Server Units

PedastlasaRcksBlades

¾Blade Servers have three types of network traffic: ¾LAN: Ethernet ¾SAN: Fiber Channel ¾IPC: Myrinet, Quadrics, Infiniband etc. ¾Eachtyamepytciffar tecadide eirqure tc:snoenetcrdni ¾Switches, IO Cards, cables and management ¾Different management tools ¾Significant future challenges: ¾Cost, Power, Thermal etc. ¾Overall, high TCO

Scaling Multiple IO Fabrics within the blade system is a challenge!

I/OConsolidation in Blade Servers

Processor Memory

I/O I/O I/O

Storag I

     

N

Processor Memory

I/O Subsystem

Storage IPC LAN

I/O Consolidation reduces Capital Expense and Operational Expense

Storage Components Market

¾iSCSI adoption has been slow despite being more cost effective ¾FC continues to be the dominant SAN technology ¾F500 IT concerns include

¾Security

¾Performance -- Ethernet behaves poorly in congested environments, packet drops significant, adversely affects storage traffic

Improving Ethernet congestion management can accelerate iSCSI adoption – addresses IT perception & reality