IP Routing. Overview Static routing Default routing Dynamic routing.
Traffic Matrix Estimation for Delta Routing
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Traffic Matrix Estimation for Delta Routing George Porter and Minwen Ji, Ph.D. Compaq/HP Systems Research Center Problem Setup Delta Routing Proposed Optimization Traffic Matrix Estimation Congestion Avoidance Future Work VPN Internet Congestion •Developed at SRC, this is an enabling technology for this proposal •Take advantage of intranet’s connectivity to the Internet to forward traffic across the private network •Send traffic over Virtual Private Network (VPN) tunnels if intranet is getting congested/overutilized • Enterprises connect their locations together with leased, private lines called an Intranet • Such links are very expensive, and so are usually not overprovisioned • Because of that, congestion can occur • How to avoid this problem? Assumptions • Subset of nodes have Internet connectivity • A link state routing protocol runs on the physical, leased network • To simplify the traffic estimation, we assume no multi-path routing on the physical network Node 1 2 3 4 5 1 1.2 2.7 0.6 2.2 2 2.9 3.0 0.1 3.3 3 4.0 1.5 4.3 3.9 4 4.1 0.3 0.4 4.3 5 1.2 0.7 4.9 0.8 • Nodes know traffic for (src,dst) pairs that transit through them • For other pairs, they rely on periodic announcements from other nodes R outers m onitor traffic transiting through them R outers periodically exchange traffic m easurem ents TM estim ates + routing table = prediction of congestion on links C ongestion predicted to endpoint? Send over physical netw ork Forw ard past congestion via VPN tunnel No Yes TM estimates Routing Table C ongestion Estim ates Example traffic matrix • Accuracy depends on frequency of periodic updates as well as burstiness of traffic • This process is performed at each node independently • Thus, if a bad prediction is made, the distant, congested node will repeat the process • Implementation in the ns simulator is in progress • First experiment: given various traffic patterns and update frequencies, how accurate is the TM estimation? • Second experiment: as the accuracy of the TM varies, how well can we predict congestion? • Third experiment: overall performance in a large, realistic network topology
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Traffic Matrix Estimation for Delta Routing. George Porter and Minwen Ji, Ph.D. Compaq/HP Systems Research Center. Problem Setup. Delta Routing. Proposed Optimization. Developed at SRC, this is an enabling technology for this proposal - PowerPoint PPT Presentation
Transcript of Traffic Matrix Estimation for Delta Routing
Traffic Matrix Estimation for Delta Routing
George Porter and Minwen Ji, Ph.D.
Compaq/HP Systems Research CenterProblem Setup Delta Routing Proposed Optimization
Traffic Matrix Estimation
Congestion Avoidance
Future Work
VPN
Internet
Congestion
•Developed at SRC, this is an enabling technology for this proposal•Take advantage of intranet’s connectivity to the Internet to forward traffic across the private network•Send traffic over Virtual Private Network (VPN) tunnels if intranet is getting congested/overutilized
• Enterprises connect their locations together with leased, private lines called an Intranet• Such links are very expensive, and so are usually not overprovisioned• Because of that, congestion can occur• How to avoid this problem?
Assumptions• Subset of nodes have Internet connectivity• A link state routing protocol runs on the physical, leased network• To simplify the traffic estimation, we assume no multi-path routing on the physical network
Node 1 2 3 4 51 1.2 2.7 0.6 2.22 2.9 3.0 0.1 3.33 4.0 1.5 4.3 3.94 4.1 0.3 0.4 4.35 1.2 0.7 4.9 0.8
• Nodes know traffic for (src,dst) pairs that transit through them• For other pairs, they rely on periodic announcements from other nodes
Routers monitortraffic transitingthrough them
Routersperiodically
exchange trafficmeasurements
TM estimates +routing table =prediction of
congestion on links
Congestionpredicted toendpoint?
Send overphysicalnetwork
Forward pastcongestion via
VPN tunnel
NoYes
TMestimates
RoutingTable
Congestion Estimates
Example traffic matrix
• Accuracy depends on frequency of periodic updates as well as burstiness of traffic
• This process is performed at each node independently• Thus, if a bad prediction is made, the distant, congested node will repeat the process
• Implementation in the ns simulator is in progress• First experiment: given various traffic patterns and update frequencies, how accurate is the TM estimation?• Second experiment: as the accuracy of the TM varies, how well can we predict congestion?• Third experiment: overall performance in a large, realistic network topology
