Point to multipoint file transfer protocol over UDP using automatic repeat requests (ARQ)

usage:

  p2mpclient server-1 server-1-port [server-2 server-2-port ... server-r server-r-port] file-name N MSS max-rtt
             server-n      - server-n's ip address (at least 1 server should be specified, max 10)
             server-n-port - server-n's port (at least 1 server should be specified, max 10)
             file-name     - file to be transferred
             N             - window size
             MSS           - maximum segment size of each segment (< 1500)
             max-rtt       - maximum rtt (in ms) of all receivers (found using rttserver and rttclient programs)

  p2mpserver port# file-name N p
             port#     - port number to which the server is listening
             file-name - file where the data will be written
             N         - window size
             p         - probability of packet loss, ranges between 0 and 1

  rttserver port
            port - port to bind to

  rttclient ip-addr port n
            ip-addr - ip-address of the server
            port    - port of the server
            n       - number of packets to be sent
 
Steps:
  1. make
  2. run rttserver and rttclient to determine rtt of the connection
  3. run p2mpserver and p2mpclient to start file transfer

Files of concern:
  1. p2mp.c[h] - common functions used by p2mpserver, p2mpclient, rttserver and rttclient
  2. p2mpclient.c[h] - entry point function for p2mpclient
  3. rdt_send.c - data aggregator thread
  4. sender_thread.c - packet sending thread for p2mpclient
  5. receive_thread.c - packet receiving thread for p2mpclient
  6. timer_thread.c - timer expiry thread
  7. p2mpserver.c[h] - entry point function for p2mpserver