ucb tools for smart networks jean walrand bits (berkeley information technology & systems) u.c....
Post on 19-Dec-2015
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UCBTools for Smart Networks
Jean WalrandBITS
(Berkeley Information Technology & Systems)U.C. Berkeley
www.eecs.berkeley.edu/~wlr/mascots2000
UCB Outline
What are Smart Networks? Why Smart Networks? Tools for Smart Networks Project Example 1: DiffServ Example 2: Bandwidth Allocation Conclusions
UCB What are Smart Networks?
Measure
Analyze
Modify
UCB Why Smart Networks?
Before: “Simple Network”
IPTransport
ApplicationsTransport
Applications
Client Server
Network
UCB Why Smart Networks? (continued)
Now: “Complex Network”
Network
Application Servers, Content Servers
Caches, Traffic Shapers,Redirection Agents, Processing
UCB Why Smart Networks? (continued)
• Simple Network:• IP Forwarding • Routing Table Updates• DNS• Intelligence in Hosts
• Complex Network:• New Functions • New Transport Services (e.g., CoS, SLAs)• Needs Intelligence in Network
UCB Why Smart Networks? (continued)
INTERNET
IP
LANs, ATM, ...
Applications
Success of Simplicity
Success of Complexity
TELEPHONE
SS7, Billing, ...
OC-n, DS-n, UTP
Applications
UCB Why Smart Networks? (continued)
Probably not very desirable!
INTERNET
IP
LANs, ATM, ...
Applications
UCB Why Smart Networks? (continued)
INTERNET
IP
LANs, ATM, ...
Applications
IP
LANs, ATM, ...
Applications
M/A/M
Tools for Planning, Design,
Operations
UCB
Tools for Smart Networks Project
Joint UCB - Cisco Project DARPA Funding + Cisco Combines
• Measurements • Analysis & Simulation• Real-time Control
Objective: Product
UCB
Tools for Smart Networks Project (cd)
Utility
Comprehension
Simulations
Measurements
AnalysisIntegrated
Tools
UCB
Tools for Smart Networks Project (cd)
Cisco: David Jaffe (Lead Investigator) Karl Auerbach (Lab Design and
Implementation) Anna Charny (MPLS)
UCB Anantharam, Tse, Varaiya, Walrand Stavros Tripakis (post-doctoral scholar) About 6 graduate students
TEAM:
UCB Example 1: DiffServ
Goal: CoS without per-connection state
No route-pinning Planning and operations based on
aggregate statistics and worst-case routing Peer-to-peer SLAs that specify total rate
but not traffic destination
Solution:
UCB Example 1: DiffServ (continued)
Cloud 2Cloud 1PolicingShaping
SLA
UCB Example 1: DiffServ (continued)
Ingress 1
Ingress 3
Ingress 1
Ingress 2
Ingress 3
Typical Case Worst CaseIngress 2
Bottleneck Link
DiffServ SLA: Worst Case Admission Control
Terribly wasteful!
UCB Example 1: DiffServ (continued)
New
Admit if peak(new) < Gap at all times
Capacity
Mean + 2.4s Gap
DiffServ SLA: Measurement-Based Admission Control
UCB Example 1: DiffServ (continued)
How well does this approach work?
Simulation study:• Construct traffic model (parametric FBM)• Validate model against measurements• Simulate admission control policy• Test fraction of SLAs that see congested links and level of congestion
Experimental study (coming year)• Implement measurements and admission control• Evaluate performance
UCB
Example 2: Bandwidth Allocation
Problems: How to share bandwidth How to renegotiate SLAs
Issues: Scalability Efficiency Fairness, Optimality, ...
UCB
Example 2: Bandwidth Allocation (cd)
Proposed Adaptation Scheme: Renegotiate “blocks” of permits based on thresholds
10
10
35
3
4
6
415
567
5
67
20
40
UCB
Example 2: Bandwidth Allocation (cd)
Implementation Peer-to-peer negotiation between
bandwidth brokers Two versions
Shadow prices Actual pricing
UCB
Example 2: Bandwidth Allocation (cd)
How well does this approach work?
Simulation study:• Birth/Death Model of Bandwidth• Study Efficiency vs. Rate of Renegotiation