Internet2 Measurement Perspective Guy T. Almes Matt Zekauskas SD Measurement Workshop June, 1999

General Goal of Internet2 Support advanced applications High bandwidth flows Low latency Low loss Advanced services Multicast Quality of service guarantees

‘My application has a problem’ Application, End-host, Network? Passive measurements could help divide the problem Consistent measurements throughout Internet2 infrastructure could help diagnose network problems

Backbone ‘A’ Backbone ‘B’

Backbone ‘A’ Backbone ‘B’

Backbone ‘A’ Backbone ‘B’

Other Measurement Goals (Forward) network engineering Enable network research Feedback to applications Operational data performance, flows, anomalies Network characterization how used? load response? SLS?

Measurement Classification Utilization [usually SNMP] Active measurements ~Performance (one-way delay, loss, throughput) Passive measurements ~Traffic characterization Routing [usually BGP/traceroute]

Utilization Technically “easy”; “boring” Coordinate type, frequency … and reporting A small number of frequency multiples 15 sec, 1 min, 4 min

Utilization II Standardize file format Single access mode Example: relative URL for routers Example: single I2 measurement page

Active measurements delay loss throughput? (don’t want to interfere with apps) my point of view: approximately Surveyor, +(?) throughput Packet sizes? Distribution?

Passive Measurements Question: how apply passive measurements effectively in a consistent fashion? Something that is useful to all? Each additional probe adds value? Perhaps flow data What about packet headers? And security...

Routing Can’t just measure one point: policy E-E measurements: surveyor AMP consistency/access problems a-la utilization RA? Routing protocol sniffing? Traceroute observatories?

Examples Remote microscope Videoconference from Lund to Pittsburgh UDP, blasting packets OCxMON shows more packets than capacity Videoconference from Lund to Pittsburgh Packet loss… don’t know why

Desires Want some way to know where loss occurs when it happens (or delay) Advanced service debugging Multicast QoS (QBone designing measurement in) Service level specification conformance

Desires Application reflectors along with routers? (Is this measurement?)

Summary Consistent measurement of That are made generally available Utilization Performance Traffic Characterization That are made generally available In support of applications and the networks themselves

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