QoS Aware Path Protection for MPLS Networks



What is it about ?   

Multiprotocol Label Switching integrates Layer 2 information about network links (bandwidth, latency, and utilization) into Layer 3 (IP) in order to simplify and improve IP-packet exchange. The problem of path protection looks at fast rerouting of critical traffic along pre-allocated paths in case of a node/link failure. Our focus has been to develop algorithms to provide QoS guarantees even in case of failure along with efficient bandwidth reservation. 

We considered a new approach based on dividing the entire route into segments and protecting each segment separately. We have developed algorithms for providing bounded switch over time after failure, end-to-end delay, jitter, their combinations and bound on reliability. 

We tested the algorithms in a self developed LSP Admission Control Simulator (in C++) and the algorithms perform well compared to existing protection schemes, utilizing lesser bandwidth. We have also developed a visualization system for these algorithms as a part of the project. We also looked at mechanisms for fault detection, notification and path switching. Sharing of bandwidth in the network was also implemented to conserve resources


This project received the “Best B.Tech Project Award” in CS Department and also the ICIM Stay Ahead Award for the best project in Information Technology and Computing Sciences.

Under guidance of Prof. B.N. Jain, Department of Computer Science & Engineering, IIT Delhi

Here is a flash animation for a quick look at the concept

The above animation shows a general idea of working of Segment-based Protection. Click on the "Show Fault" Button to activate the fault and Protection Mechanisms

Click here to view a more sophisticated Flash animation which illustrates the algorithm concepts (see Thesis and Paper/Presentations for algorithm details)


Thesis and Paper

Final Thesis (PDF)    (PS Format)



Ashish Gupta*, Ashish Gupta*, B.N. Jain*, Satish Tripathi^, QoS Aware Path Protection Schemes for MPLS Networks, In Proceedings of International Conference of Computer Communications, August 2002

* Indian Institute of Technology, Delhi , India
^ University of California at Riverside, California


Selected presentations

For Best BTP Award

This talk gives detailed insight into our algorithms with animations and step-by-step explanations.

2002 May : Final Presentation

The final talk given before the Thesis Committee.

The Presentation given at ICCC 2002 Conference.

This gives a quick intro to the concept.