NAME

       mm-link  -  UNIX shell connected to an emulated link with a user-specified packet-delivery
       schedule.

SYNOPSIS

       mm-link uplink downlink [-- command...]

DESCRIPTION

       mm-link is a network emulation tool that emulates links using packet delivery trace  files
       (uplink  for the uplink direction and downlink for the downlink direction) provided on the
       command line. mm-link uses clone(2) to fork a new shell in a distinct  network  namespace.
       uplink_trace_file  emulates  the link from mm-link to the Internet and downlink_trace_file
       emulates the link from the Internet to mm-link.

       mm-link can emulate both time-varying links, such as cellular links, and links with  fixed
       link  speeds.  When  a  packet  arrives at the link (from either the Internent or from mm-
       link), it is directly placed into one of two  packet  queues  depending  on  its  intended
       direction:  the  uplink  queue  or the downlink queue.  mm-link releases packets from each
       queue based on the corresponding input packet-delivery trace.

       Each line in the trace  represents a packet delivery opportunity: the  time  at  which  an
       MTU-sized  packet can be delivered in the emulation. Accounting is done at the byte-level,
       and each delivery opportunity represents the ability to deliver 1500 bytes. Thus, a single
       line in the trace file can delivery several smaller packets whose sizes sum to 1500 bytes.
       Delivery opportunities  are  wasted  if  bytes  are  unavailable  at  the  instant  of  an
       opportunity.  When  mm-link reaches the end of an input trace file, it wraps around to the
       beginning of the trace file. mm-link can be  nested  within  delayshell  (1)  to  flexibly
       create links with a user-supplied one-way delay and a user-supplied link rate.

       To exit mm-link, simply type "exit" or CTRL-D inside mm-link.

EXAMPLE

       To emulate a 12 Mbit/s link (in each direction), make a 12 Mbit/s
       tracefile, "12Mbps_trace". This file can be of arbitrary length
       and must follow the pattern below:
       0
       1
       2
       3
       4
       5...
       The link above delivers an MTU-sized packet (1500 bytes or 12000 bits) every
       ms.

       Run mm-link with:
       $ mm-link 12Mbps_trace 12Mbps_trace

       All programs run from within mm-link are sent according
       to the packet delivery times specified in 12Mbps_trace.

       mm-link
       [...] (copyright notice omitted)

SEE ALSO

       mahimahi(1), mm-delay(1), mm-webrecord(1), mm-webreplay(1).

       Project home page: http://mahimahi.mit.edu

AUTHOR

       Mahimahi was written by Ravi Netravali, Anirudh Sivaraman, Greg D. Hill, Deepak Narayanan,
       and Keith Winstein.

BUGS

       Please report bugs to mahimahi@mit.edu.

                                          February 2014                                mm-link(1)