March 22, 2010IETF 77 – Anaheim, USA1 A method for IP multicast performance monitoring draft-cociglio-mboned-multicast-pm-00 Alessandro Capello Luca Castaldelli Mauro Cociglio Alberto Tempia Bonda

MBONED WGdraft-cociglio-mboned-multicast-pm-002 Motivation Artifacts seen by IPTV users are mainly related to Packet Loss (PL) ­IPTV service is sensitive to very low PL rates (10 -4 and below) Develop PL monitoring tools for ISP ’ s multicast production network ­Provide to Network Operations Centers suitable views on network behavior to address in near real-time complaints coming from Customer Care ­Detect, measure and localize PL events Drive the implementation of network solutions to improve the Quality of Experience

MBONED WGdraft-cociglio-mboned-multicast-pm-003 Service Providers requirements * SLA monitoring and verification ­Not only reachability test Fault localization ­Not only end-to-end measurement Inline data-plane measurement ­Performance measurements based on real user traffic Scalable solution Self-contained ­Not dependent on other protocols (RTP, IGMP, SNMP MIB, etc … ) *Requirements for IP multicast performance monitoring (draft-bipi-mboned-ip-multicast-pm- requirement-00.txt)

MBONED WGdraft-cociglio-mboned-multicast-pm-004 Characteristics The draft describes a monitoring methodology which fulfills the requirements of the previous slide In addition it is: ­ vendor/technology independent ­ with minimum impact on routers

MBONED WGdraft-cociglio-mboned-multicast-pm-005 Performance measurement methodology Performance Monitoring Methodology steps: ­Marking of IPTV traffic ­Enabling packet counting / timestamp on router interfaces ­NMS data retrieval ­NMS Performance Measurement and Fault Detection

MBONED WGdraft-cociglio-mboned-multicast-pm-006 Principle of the method Mark multicast traffic being monitored so as to create a sequence of “ blocks ” and … … count the number of packets of each “ block ” to measure packet loss … or take the timestamp of a particular packet within a block (f.i. the first packet of each block) to measure delay / jitter Block = sequence of consecutive packets with the same marking Multicast Stream MARKING COUNTING Blocks

MBONED WGdraft-cociglio-mboned-multicast-pm-007 How it works (for packet loss) Block 1375 pcks 375 pcks  0 pcks lost Block 2382 pcks 382 pcks  0 pcks lost Block 3364 pcks 359 pcks  5 pcks lost … Block n-1367 pcks 367 pcks  0 pcks lost Block n381 pcks 379 pcks  2 pcks lost Block 1Block 2Block nBlock n-1

MBONED WGdraft-cociglio-mboned-multicast-pm-008 What is needed A bit of the IP header to mark the traffic 2 counters on each interface on each router ­1 counter for blue blocks ­1 counter for orange blocks Note - Only one counter increases at a time: ­during blue blocks only the blue counter increases ­during orange blocks only the orange counter increases ­when a counter is still it can be read (the block terminated)

MBONED WGdraft-cociglio-mboned-multicast-pm-009 And for delay and jitter? Timestamp Timestamp Delay Packet 111:21: :21:  4 msec Packet 211:22: :22:  5 msec … Packet n-111:35: :21:  6 msec Packet n11:36: :22:  3 msec Packet n Timestamp Packet n-1 Timestamp Packet 2 Timestamp Packet 1 Timestamp

MBONED WGdraft-cociglio-mboned-multicast-pm-0010 What it can measure Link Measurement Node Measurement E2E Measurement Segment by Segment Measurement

MBONED WGdraft-cociglio-mboned-multicast-pm-0011 Deployment considerations Multicast Flow Identification & Path Discovery ­How many flows? Which flows? Flow Marking ­Where? How? Packet counting on Monitoring Nodes ­Where? How? Management System ­It is required to collect and elaborate data Scalability ­How many flows can be monitored? How many nodes? Interoperability ­No issues

MBONED WGdraft-cociglio-mboned-multicast-pm-0012 Field Trial Field Trial started end 2009 in Telecom Italia network: ­2 real IPTV streams monitored ­14 nodes and 50 interfaces involved ­NMS prototype to collect, elaborate and visualize data ­Only packet loss measurement ­Preliminary results are very promising

MBONED WGdraft-cociglio-mboned-multicast-pm-0013 Summary Easy implementation Vendor/technology independent Global or per-flow measurements Highly precise packet loss measurement (single packet loss) Applicable to any kind of traffic (unicast and multicast)

MBONED WGdraft-cociglio-mboned-multicast-pm-0014 Next steps Feedback and comments from the WG Feedback from the Field Trial Extension to other kind of traffic (VoIP)