Page 1 IEEE 802 March 2011 workshop Version 1.0 EEE 802 IEEE Std Resilient Packet Ring (RPR)

Page 2Version 1.0 IEEE 802 March 2011 workshop EEE 802 IEEE Std Resilient Packet Ring Overview RPR Station Normal operation Dual counter-rotating ringlets Concurrent transmission Bandwidth reuse Three traffic classes Real Time, GIR Low Delay/Jitter, CIR+EIR Best Effort Fairness Reuse of unused bandwidth Weighted allocation to EIR, best effort Plug-and-play Automatic topology discovery Robustness Sub 50 ms fault detection & restoration Fault tolerant No single point of failure

Page 3Version 1.0 IEEE 802 March 2011 workshop EEE 802 IEEE Std Phys ringlet 1 RS PHY RS PHY MAC Datapath MAC RPR Station RSPHYRSPHY MAC Datapath MAC RPR Station RS PHY RS PHY MAC Datapath MAC RPR Station RSPHYRSPHY MAC Datapath MAC RPR Station ringlet0 West PHY East PHY PHY Independence Agnostic to which PHY used RS defined for SONET/SDH and 1 and 10 Gbps Ethernet PHYs PHY Must be same speed on all links Media can be different West PHY Receiving on ringlet0 Transmitting on ringlet1 East PHY Transmitting on ringlet0 Receiving on ringlet1 MAC – Medium access controller PHY – Physical layer entity RS – Reconciliation sublayer Key:

Page 4Version 1.0 IEEE 802 March 2011 workshop EEE 802 Real SLAs BW allocations restored upon demand –Class based prioritization allows restoration within delay and jitter requirements for SLAs –Allows full utilization and hard SLAs without reserving BW FR/ATM-derived classes of service

Page 5Version 1.0 IEEE 802 March 2011 workshop EEE 802 Fairness 10 Mb/s available capacity Unfairness 6 Mb/s 4 Mb/s S1 6 Mb/s S2 6 Mb/s S3 6 Mb/s 0 Mb/s Equal Fairness 3.3 Mb/s S1 6 Mb/s S2 6 Mb/s S3 6 Mb/s 3.3 Mb/s www equal weighted shapers Weighted Fairness S1 6 Mb/s S2 6 Mb/s S3 6 Mb/s 2 Mb/s 6w unequal weighted shapers 2w 6 Mb/s 2 Mb/s

Page 6Version 1.0 IEEE 802 March 2011 workshop EEE 802 IEEE Std protection mechanisms Normal operation RPR Station Normal operation - Sub 50ms fault restoration - Two paths available between any two nodes

Page 7Version 1.0 IEEE 802 March 2011 workshop EEE 802 IEEE Std protection mechanisms Steering RPR Station Failure Steering x Directs frame on opposing ringlet that still has connectivity

Page 8Version 1.0 IEEE 802 March 2011 workshop EEE 802 IEEE Std protection mechanisms Wrapping (optional) RPR Station Failure Wrapping Transmits frame on opposing ringlet in order to route around the fault x

Page 9Version 1.0 IEEE 802 March 2011 workshop EEE 802 serviceDataUnit 2 4 fcs protcolType n IEEE Std Frame formats serviceDataUnit sa da Size (Octets) baseControl ttl 1 1 Key: da – Destination addressttl – Time to live sa – Source address fcs – Frame check sequence fcs protcolType ttlBase extendedControl hec n sa da 6 6 baseControl ttl 1 1 ttlBase extendedControl hec saExtended daExtended 6 6 Size (Octets) header payload trailer header payload trailer Basic frame format Extended frame format

Page 10Version 1.0 IEEE 802 March 2011 workshop EEE 802 Frame Header Checker IEEE Std Datapath sublayer MAC Address match – Receive, strip Multicast – Copy, transit Expired TTL - strip Else - Transit Frame Header Checker Ringlet selection Ringlet0 datapath Ringlet1 datapath Type check Control MAC service interface PHY service interface MAC control sublayer MAC datapath sublayer Spatial reuse – Ingress frames use timeslots previously used by egress frames Receive frames Transmit frames Transmit frames yield to transit frames Transit buffer Single queue or Dual queue Control packets – OAM, Topology, protection Fairness algorithm, OAM, Protection, Topology

Page 11Version 1.0 IEEE 802 March 2011 workshop EEE 802 IEEE Standards IEEE TM Resilient packet ring (RPR) access method and physical layer specifications –IEEE a-2004: Bridging of IEEE Std –IEEE b-2007: Spatially Aware Sublayer –IEEE c-2010: Protected Inter-Ring Connection All available through Get IEEE 802