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MB - NG MB-NG Technical Meeting 03 May 02 R. Hughes-Jones Manchester 1 Task2 Traffic Generation and Measurement Definitions Pass-1
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MB - NG MB-NG Technical Meeting 03 May 02 R. Hughes-Jones Manchester 2 Proposed Agenda Load Traffic Task 2.1.1 Define Simulated and Background Traffic Tools Control - logging Measurement Systems What do MB-NG NEED to measure Tech and Political Task 2.2.1 Define low level Probe Measurements Metrics Pragmatic Tools Control - logging Relation to IETF and GGF Network Metrics Draft reports Next Technical “bits&bytes” Meeting AOB
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MB - NG MB-NG Technical Meeting 03 May 02 R. Hughes-Jones Manchester 3 MB – NG SuperJANET4 Development Network (22 Mar 02) Gigabit Ethernet 2.5 Gbit POS Access 2.5 Gbit POS core MPLS Admin. Domains Dark Fiber (SSE) POS WorldCom SuperJANET4 Production Network Leeds SJ4 Dev C-PoP Warrington 12416 SJ4 Dev C-PoP London 12416 UCL OSM-4GE- WAN-GBIC OSM- 1OC48- POS-SS UCL OSM-4GE- WAN-GBIC MCC OSM-4GE- WAN-GBIC OSM- 1OC48- POS-SS MAN OSM-4GE- WAN-GBIC RAL OSM-4GE- WAN-GBIC OSM- 1OC48- POS-SS RAL OSM-4GE- WAN-GBIC OC48/POS- SR-SC SJ4 Dev ULCC 12016 OC48/POS- SR-SC WorldCom SJ4 Dev C-PoP Reading 12416 OC48/POS- LR-SC WorldCom ULCC
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MB - NG MB-NG Technical Meeting 03 May 02 R. Hughes-Jones Manchester 4 Defining Background Traffic Regular traffic - constant size packet, regular spaced in time Poisson traffic - constant size, exponential spacing to form transient queues IETF traffic mix - different sizes and different probability of each size sent Play back of real traffic patterns generated from packet headers pre-recorded from suitable points of the production network. This might include: Video Conference traffic -> play back - rude/crude tools UCL real conf playback tool Multicast ? General traffic captured at edge of a site, e.g. Manchester Do tests with a gen to see what gets dropped 0.5 Gbit typical poeak UCL Web-bursty traffic – web mirror – wget Need to be able to reproduce traffic so no TCP as non-linear. Statistical reproducible OK In general UDP best mto understand the net but some TCP bground is good too Self-Similar What about generating MPLS frames?? Consider UDP TCP flows Need ToS / QoS to be set How to control Start Stop measure load as function of time – links and Queues Start and end numbers How to get data from the core routers – eg need PC in the PoP?
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MB - NG MB-NG Technical Meeting 03 May 02 R. Hughes-Jones Manchester 5 Defining the Measurements (1) Suggested Approach What do we need to measure for MB-NG How do we analyse it ? What do we expect ? What does it tell us ? NOT defining the measurement matrix – link to Task5 Policies General Conditions include IP operation MPLS QoS/Diffserv Apply techniques to understand the performance of: PC-PC Routers and (LAN) interconnects Development Core – useful to know about the GSR performance details how do we load it (PC only 1Gig I/f – may be Spirant – Dante OC48 kit. End-2-end
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MB - NG MB-NG Technical Meeting 03 May 02 R. Hughes-Jones Manchester 6 Defining the Measurements (10) UDP round-trip latency vs packet size Sum of dt/dl transfer rates Router performance Stack performance UDP round-trip histograms Indication of network load Switching / transport effects – spikes UDP 1-way delay UDP throughput vs Packet size and transmit delay Throughput behaviour The effect of load on switch/router throughput Offered vs achieved throughput UDP Packet Loss vs transmit rate and burst size Loss rate ( note location of loss) Packet loss distribution as function of time Packet loss for simulated “TCP bursts” Buffer sizes in the path Detect packet re-ordering UDP Inter-frame Jitter as function of packet transmit spacing Indication of network load Behaviour of end system NICs
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MB - NG MB-NG Technical Meeting 03 May 02 R. Hughes-Jones Manchester 7 Defining the Measurements (11) TCP round-trip latency vs Message size Sum of dt/dl transfer rates (Router performance) Stack / protocol performance Detect Packet size dependencies TCP round-trip histograms Indication of network load (Switching / transport effects – spikes) Stack / protocol performance TCP throughput vs Message size and transmit delay Throughput behaviour cf UDP Offered vs achieved throughput Packet loss distribution as function of time + Re-transmit rate Loss as func of pkt rate eg keep the data rate the same change pkt size – multi-streams TCP throughput vs Window size / TCP tuning TCP throughput vs number of streams Stream throughput - benefits Packet loss distribution as function of time + Re-transmit rate Effect on Network TCP Protocol behaviour - tcptrace What are the “burst” lengths Effect of routers / end system NICs All this for WRED Wt fair Qing data rate const and ch pkt size – chack how well the routers do the Qing
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MB - NG MB-NG Technical Meeting 03 May 02 R. Hughes-Jones Manchester 8 Next Steps Who does what investigation Draft reports Next Technical “bits&bytes” Meeting 24 May Manchester Discussion! Time
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