NAME

       bwctld - Bandwidth Control server.

SYNOPSIS

       bwctld  [  -a  auth_mode ] [ -c conf_dir ] [ -e facility ] [ -f ] [ -G group ] [ -h ] [ -R var_dir ] [ -S
       nodename:port ] [ -U user ] [ -v ] [ -Z ]

DESCRIPTION

       bwctld is a server program designed to schedule and run  Iperf,  Thrulay  or  Nuttcp,  Ping,  Traceroute,
       Tracepath, and Owamp tests.

       Aside  from actually running network measurement tests, the main function of bwctld is to determine which
       tests are allowable based upon the policy restrictions configured by the system administrator.

       bwctld was designed to be run as a stand-alone daemon process. It uses the classic accept/fork  model  of
       handling new requests.

       Most  of  the command line options for bwctld have analogous options in the bwctld.conf file. The command
       line takes precedence.

OPTIONS

       -a auth_mode
              Specify the authentication modes the server is willing to use for communication. auth_mode  should
              be set as a character string with any or all of the characters "AEO". The modes are:

              A      [A]uthenticated. This mode encrypts the control connection.

              E      [E]ncrypted.  This  mode  encrypts the control connection. If the test supports encryption,
                     this mode will additionally encrypt the test stream. (Encryption of the test stream is  not
                     currently supported, so this mode is currently identical to authenticated.)

              O      [O]pen. No encryption of any kind is done.

              The server can specify all the modes with which it is willing to communicate. The most strict mode
              that both the server and the client are willing to use will be selected.

              Default:
                     "AEO".

       -c conf_dir
              Specify the directory that holds the bwctld configuration files.

              Default:
                     Current working directory.

       -e facility
              Syslog facility to which messages are logged.

              Default:
                     LOG_DAEMON

       -f     Enables the bwctld daemon to run with root permissions. There are legitimate reasons to run bwctld
              as root, but it is risky. Forcing this additional option will make it less likely root permissions
              are accidently used.

       -G group
              Specify  the  gid  for  the  bwctld process. group can be specified using a valid group name or by
              using -gid. This option is only used if bwctld is started as root.

       -h     Print a help message.

       -R var_dir
              Specify the directory to hold the bwctld.pid file.

              Default:
                     Current directory

       -S nodename:port
              Specify the address and port on which bwctld will listen for requests.  nodename can be  specified
              using  a  DNS  name  or using the textual representation of the address. It is possible to set the
              source address without setting the port simply by leaving off the ':' and port  specification.  If
              an  IPv6 address is specified, note that the accepted format contains nodename in square brackets,
              such  as:  [fe80::fe9f:62d8].  This  ensures  the  port  number  is  distinct  from  the   address
              specification.

              Default:
                     nodename is wildcarded as any currently available address.  port is 4823.

       -U user
              Specify  the uid for the bwctld process. user can be specified using a valid user name or by using
              -uid. This option is only used if bwctld is started as root.

       -v     Set verbose output. Messages will only go to syslog unless the -Z option is specified.

       -Z     Run the master bwctld process in the foreground. In this  mode,  error  messages  are  printed  to
              stderr  as  well  as  being  sent  to syslog. Also, normal terminal controls are available. (i.e.,
              <Cntr-C> will cause the daemon to kill  it's  child  processes  and  exit.)  This  is  useful  for
              debugging.

REQUIREMENTS

       The bwctld daemon prefers a reasonably synchronized clock. It is scheduling tests and needs to be sure it
       has  the  same  idea  of  when  a test should take place as does the peer test system.  Therefore, bwctld
       attempts to use NTP specific system calls to determine the accuracy of the local clock. If  those  system
       calls are unavailable, or the administrator has set the allow_unsync option in the bwctld.conf file, then
       bwctld will blindly accept tests assuming the clock is synchronized to within the sync_fuzz value that is
       also  defined  in  the  bwctld.conf  file.  If  this  assumption  does  not hold true, then the test will
       eventually fail. Unfortunately, because the time offset is not detected early, this test will have  taken
       up a schedule slot.

FILES

       bwctld.pid
       bwctld.conf
       bwctld.limits
       bwctld.keys

SEE ALSO

       There  are  more  details  on configuring the bwctld daemon in the bwctld.conf(5) manual page. Details on
       configuring the policy is in the bwctld.limits(5) and bwctld.keys(5) manual pages.   Information  on  the
       client  is  in  the  bwctl(1)  manual  page.   For  more  of  an  overview  of the full functionality and
       architecture see the http://software.internet2.edu/bwctl/ web site.

       For details on Iperf3, see the https://github.com/esnet/iperf web site.

       For details on Iperf, see the http://sourceforge.net/projects/iperf web site.

       For details on Nuttcp, see the http://www.wcisd.hpc.mil/nuttcp/Nuttcp-HOWTO.html web site.

       For details on Owamp, see the http://software.internet2.edu/owamp web site.

ACKNOWLEDGMENTS

       This material is based in part on work supported by the National Science Foundation (NSF) under Grant No.
       ANI-0314723. Any opinions, findings and conclusions or recommendations expressed  in  this  material  are
       those of the author(s) and do not necessarily reflect the views of the NSF.

                                                     $Date$                                            bwctld(8)