28-08-2009, 02:04 AM
A New TCP For Persistent Packet Reordering
Abstractâ€Most standard implementations of TCP perform poorly when packets are reordered. In this paper, we propose new version of TCP that maintains high throughput when reordering occurs and yet, when packet reordering does not occur, is friendly to other versions of TCP. The proposed TCP variant, or TCP-PR, does not rely on duplicate acknowledgments to detect packet loss. Instead, timers are maintained to keep track of how long ago a packet was transmitted. In case the corresponding acknowledgment has not yet arrived and the elapsed time since the packet was sent is larger than a given threshold, the packetis assumed lost. Because TCP-PR does not rely on duplicate acknowledgments, packet reordering (including out-or-order acknowledgments) has no effect on TCP-PRâ„¢s performance. Through extensive simulations, we show that TCP-PR performs consistently better than existing mechanisms that try to make TCP more robust to packet reordering. In the case that packets are not reordered, we verify that TCP-PR maintains the same throughputs typical implementations of TCP (specifically, TCP-SACK) and Shares network resources fairly. Furthermore, TCP-PR only requires changes to the TCP sender side making it easier to deploy.
HARDWARE SPECIFICATION
Processor : Any Processor above 500 MHz.
Ram : 128Mb.
Hard Disk : 10 GB.
Compact Disk : 650 Mb.
Input device : Standard Keyboard and Mouse.
Output device : VGA and High Resolution Monitor.
SOFTWARE SPECIFICATION
Language : Java1.3
Front End Tool : Swing
Operating System : Windows 98.
