Emulation of Differentiated Services in VNUML

CS680 Class ProjectCourse Instructor : Prof. Anirudha SahooProject Team members :

Vijay Gabale (07305004)Sagar Bijwe (07305023)

Manish Kumar (07405701)

Agenda

Motivation Network set up in VNUML Architecture Implementation details Demo Experiments and Results Observations Future scope and Conclusion

Motivation

Implementation of theoretical concepts into practice

Get hands dirty with scheduling, token bucket, IP address prefix matching schemes

Interesting questions What is order of improvement achieved by DS

enabled service in terms of delay, jitter and throughput?

How do real time flows behave in DS enabled network?

Architecture

ClientNetworkRouter

Core NetworkBoundary

Router

Core NetworkCore

RouterClient A

Client NetworkRouter

Client B

ClassificationMarking

Drop Priority

SchedulingForwarding

Classification – Multi-Trie Approach

Destination trie

Source trie

0

0 1

F1 F2

F1 0 0F2 0 1F3 0 9

dst src

F3

19

9

Drop Priority – Dual Token Bucket

PIR/PBS CIR/CBS green

yellow

red

Token bucket P Token bucket C

Two-Rate Three-Color Marker

Experimental Set Up in VNUML

Customer Network

Core Network

Boundary Router

Forwarding Router

Customer Network

Server

client client

What is delay improvement?

Delay decreases considerably in DS enabled network for EF flow.

Jitter for DS enabled flow remains fairly constant.

What is jitter varying?

How is throughput varying for two flows?

Throughput for DS enabled flow was greater than disable flow.

What is the number of packets delivered for two flows?

EF flow gets priority in terms of packet scheduling and delivery.

What is number of packets dropped for two flows?

EF flow gets priority in terms of packet scheduling and delivery.

What is the effect of weight given to classes? (delay)

Flow with more weight has lesser delay in DS enabled network.

What is the effect of weight given to classes? (throughput)

Flow with more weight has more throughput in DS enabled network.

Observation The service given to one of two real time flows (EF) in the

experiment was quite predictable. This is also in accordance

with that DiffServ does not guarantee any end to end delay but

provides sufficient resources to have improvement as

compared to other flows.

As we increased the token generation rate of one of the flows,

more number of packets of the flow got admitted which in turn

resulted lower number of packets getting dropped, lesser delay

and higher throughput.

Conclusion

DiffServ improves the performance of real time flows. (about 25% increase in terms of delay and throughput)

The token bucket parameters, if set

appropriately, are helpful in admission control.

References

“An Architecture for Differentiated Services” - RFC 2475

“Virtual Network User Mode Linux” - “http://www.dit.upm.es/vnumlwiki/”