Service prioritization among different traffic classes is an important goal for the Internet. Conventional approaches to solving this problem consider the existing best-effort class as the low-priority class, and attempt to develop mechanisms that provide "better-than-best-effort" service.
We explore the opposite approach, and devise a new distributed algorithm to realize a low-priority service (as compared to the existing best effort)from the network endpoints. To this end, we develop TCP Low Priority (TCP-LP), a distributed algorithm whose goal is to utilize only the excess network bandwidth as compared to the "fair share" of bandwidth as targeted by TCP. The key mechanisms unique to TCP-LP congestion control are the use of one-way packet delays for early congestion indications and a TCP-transparent congestion avoidance policy.
The results of our simulation and Internet experiments show that:
1) TCP-LP is largely non-intrusive to TCP traffic.
2) Both single and aggregate TCP-LP flows are able to successfully utilize excess network bandwidth; moreover, multiple TCP-LP flows share excess bandwidth fairly
3) Substantial amounts of excess bandwidth are available to the low-priority class, even in the presence of "greedy" TCP flows
4) Despite their low-priority nature, TCP-LP flows are able to utilize significant amounts of available bandwidth in a wide-area network environment
• Processor: Intel Pentium IV Processor
• Random Access Memory: 128MB
• Hard Disk: 20GB
• Processor Speed: 300 min
Operating System : Windows 98,2000,xp
Tools : jdk1.5.0
Technologies : Java Swings, JDBC, Servlets