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A method for IP multicast performance monitoring. draft-cociglio-mboned-multicast-pm-01. Alessandro Capello Luca Castaldelli Mauro Cociglio Alberto Tempia Bonda. History. First presented at IETF 77 in Anaheim At IETF 78 the topic was presented in IPPM Outside the scope of the charter
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A method for IP multicast performance monitoring draft-cociglio-mboned-multicast-pm-01 Alessandro Capello Luca Castaldelli Mauro Cociglio Alberto Tempia Bonda IETF 79 – Beijing, China
History • First presented at IETF 77 in Anaheim • At IETF 78 the topic was presented in IPPM • Outside the scope of the charter • Update from -00 to -01 • Mainly editorial changes • Added security considerations draft-cociglio-mboned-multicast-pm-01
Motivation Artifacts seen by IPTV users are mainly related to Packet Loss 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 WG draft-cociglio-mboned-multicast-pm-01
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-02) draft-cociglio-mboned-multicast-pm-01
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 draft-cociglio-mboned-multicast-pm-01
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 draft-cociglio-mboned-multicast-pm-01
MARKING Block = sequence of consecutive packets with the same marking Blocks Multicast Stream COUNTING COUNTING COUNTING 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 draft-cociglio-mboned-multicast-pm-01
Block n Block n-1 Block 2 Block 1 How it works (for packet loss) Block 1 375 pcks 375 pcks0 pcks lost Block 2 382 pcks 382 pcks0 pcks lost Block 3 364 pcks 359 pcks5 pcks lost … Block n-1367 pcks 367 pcks0 pcks lost Block n 381 pcks 379 pcks2 pcks lost draft-cociglio-mboned-multicast-pm-01
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 (block has terminated) draft-cociglio-mboned-multicast-pm-01
Packet nTimestamp Packet n-1Timestamp Packet 2Timestamp Packet 1Timestamp And for delay and jitter? Timestamp Timestamp Delay Packet 1 11:21:07.483 11:21:07.4874 msec Packet 2 11:22:08.621 11:22:08.6265 msec … Packet n-1 11:35:09.226 11:21:09.2326 msec Packet n 11:36:08.790 11:22:08.7933 msec draft-cociglio-mboned-multicast-pm-01
Segment by Segment Measurement LinkMeasurement NodeMeasurement E2E Measurement What it can measure draft-cociglio-mboned-multicast-pm-01
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 draft-cociglio-mboned-multicast-pm-01
Field deployment • Field Trial started end 2009 in TI network: • 2 real IPTV streams monitored • 2 Metro Area Networks (MAN) involved: Turin and Naples • 30 nodes and 100 interfaces involved • Rome MAN activation by end 2010 • NMS prototype to collect, elaborate and visualize data • Only packet loss measurement • Preliminary results are very promising • Positive feedback from TI Operations draft-cociglio-mboned-multicast-pm-01
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) draft-cociglio-mboned-multicast-pm-01
Next steps • Feedback and comments from the WG • Deployment extension to all 30 TI MANs • Extension to other kind of traffic (VoIP) draft-cociglio-mboned-multicast-pm-01