In this laboratory programming assignment you will be writing the sending and receiv

ing transportlevel code for implementing a simple reliable data transfer protocol

There are two versions of this lab the AlternatingBitProtocol aka stopandwait

version and the GoBackN version This lab should be fun since your implementation will

dier very little from what would be required in a realworld situation

Since you probably don t have standalone machines with an OS that you can modify

your code will have to execute in a simulated hardwaresoftware environment However the

programming interface provided to your routines ie the code that would call your entities

from above and from below is very close to what is done in an actual UNIX environment

Stoppingstarting of timers are also simulated and timer interrupts will cause your timer

handling routine to be activated