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stunclient(1)

NAME

   stunclient - command line app for the STUN protocol

SYNOPSIS

   stunclient [OPTIONS] server [port]

DESCRIPTION

   stunclient  attempts  to  discover  the  local  host's  own external IP
   address, obtain a port mapping, and optionally discover  properties  of
   the  Network  Address  Translator  (NAT)  between  the host and the the
   server.

OPTIONS

   The following options are supported.

          --mode MODE
          --localaddr INTERFACE
          --localport PORTNUMBER
          --family IPVERSION
          --protocol PROTO
          --verbosity LOGLEVEL
          --help

   Details of each option and parameters are as follows.

   server

   The server parameter is the IP address or FQDN of the remote server  to
   perform the binding tests with.  It is the only required parameter.

      *   *   *   *   *

   port

   The  port parameter is an optional parameter that can follow the server
   parameter.  The default is 3478 for UDP and TCP.

      *   *   *   *   *

   --mode MODE

   Where MODE is either "basic" or "full".  "basic" mode  is  the  default
   and  indicates that the client should perform a STUN binding test only.
   "full" mode indicates that the client should attempt  to  diagnose  NAT
   behavior  and filtering methodologies if the server supports this mode.
   The NAT filtering test is only supported for UDP.

      *   *   *   *   *

   --localaddr INTERFACE or IPADDRESS

   The value for this option may the name of an interface (such as  "eth0"
   or "lo").  Or it may be one of the available IP addresses assigned to a
   network interface present on the host (such  as  "128.23.45.67").   The
   interface  chosen  will  be  the  preferred  address  for  sending  and
   receiving responses with the remote server.  The default is to let  the
   system  decide  which address to send on and to listen for responses on
   all addresses (INADDR_ANY).

      *   *   *   *   *

   --localport PORTNUM

   PORTNUM is a value between 1 to 65535.  This is the  UDP  or  TCP  port
   that the primary and alternate interfaces listen on as the primary port
   for binding requests.  If not  specified,  a  randomly  available  port
   chosen by the system is used.

      *   *   *   *   *

   --family IPVERSION

   IPVERSION  is  either  "4" or "6" to specify the usage of IPV4 or IPV6.
   If not specified, the default value is "4".

      *   *   *   *   *

   --protocol PROTO

   PROTO is either "udp" or "tcp".  "udp" is the default if this parameter
   is not specified

      *   *   *   *   *

   --verbosity LOGLEVEL

   Sets  the  verbosity  of  the logging level.  0 is the default (minimal
   output and logging).  1 shows slightly more.  2 and higher  shows  even
   more.

      *   *   *   *   *

   --help Prints this help page

EXAMPLES

   stunclient stunserver.org 3478
          Performs a simple binding test request with the server listening
          at "stunserver.org"

   stunclient --mode full --localport 9999 12.34.56.78
          Performs a full set of UDP NAT behavior tests  from  local  port
          9999  to  the  server  listening at IP Address 12.34.56.78 (port
          3478)

   stunclient --protocol tcp stun.selbie.com
          Performs a simple binding test using TCP to server listening  on
          the default port of 3478 at stun.selbie.com

AUTHOR

   john selbie ([email protected])



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