Provided by: openggsn_0.92-1_amd64 bug

NAME

       ggsn - Gateway GPRS Support Node.

SYNOPSIS

       ggsn --help

       ggsn --version

       ggsn  [  --fg  ]  [  --debug  ]  [  --conf file ] [ --pidfile file ] [ --statedir file ] [
       --listen host ] [ --net net ] [ --ipup script ] [ --ipdown script ]  [  --dynip  net  ]  [
       --statip net ] [ --pcodns1 host ] [ --pcodns2 host ] [ --timelimit seconds ]

DESCRIPTION

       ggsn  is  part  of the OpenGGSN project, and implements a Gateway GPRS Support Node. It is
       used by mobile operators as the interface between the Internet and the rest of the  mobile
       network infrastructure.

       The  GPRS  functionality  and  protocols  has  been  standardised  by the Third Generation
       Partnership  Project  (3GPP).  According  to  the  3GPP  specifications  a  GGSN  has  two
       interfaces: The Gn/Gp interface and the Gi interface.

       The  Gn/Gp  interface  can  be  seen as the downlink interface of the GGSN. It is used for
       communicating with the Serving GPRS Support Node (SGSN)  which  again  interfaces  to  the
       radio  access  network.  The  Gn/Gp interface uses the GPRS tunneling protocol (GTP). User
       data packets (typically IP packets) are tunneled over GTP, which again uses UDP over IP.

       The other interface can be thought of as the uplink interface, and interfaces the GGSN  to
       an  external  data  network. Gi is most often an interface to the Internet.  ggsn uses the
       TUN/TAP driver for the Gi interface. A tun network interface is established when the  ggsn
       is started.

       ggsn  will  accept  incoming  connections  from  mobile  stations through the radio access
       network and the SGSN. When a connection request is  received  the  ggsn  will  allocate  a
       dynamic  IP  address for the mobile station, and allow the mobile station to access the Gi
       interface. Connections are terminated by either the mobile station or  the  SGSN.  Runtime
       errors are reported using the Osmocom logging framework.

       Typically ggsn will be deployed with two Ethernet interfaces. One for the Gn/Gp interface,
       and one for the Gi interface. Policy routing and firewall rules should be used in order to
       separate Gi traffic from Gn/Gp traffic.

OPTIONS

       --help Print help and exit.

       --version
              Print version and exit.

       --fg   Run in foreground (default = off)

       --debug
              Run in debug mode (default = off)

       --conf file
              Read  configuration  file (default = /etc/ggsn.conf) where each line corresponds to
              one command line option, but with the leading '--' removed.  Command  line  options
              override the options given in the configuration file.

       --pidfile file
              Filename of process id file (default = /var/run/ggsn.pid)

       --statedir path
              path to directory of nonvolatile data (default = /var/lib/ggsn/)

       --listen host
              Local  interface  IP  address  to  use for the Gn/Gp interface. This option must be
              specified. For security issues it is not possible to use INADDR_ANY.

       --net net
              Network address of the Gi interface (default = 192.168.0.0/24). The network address
              is  set  during  initialisation  when  ggsn  establishes  a  tun  device for the Gi
              interface.

       --ipup script
              Script executed after the Gi tun network interface has been brought  up.   Executed
              with the following parameters: <devicename> <ip address>

       --ipdown script
              Script  executed  after the Gi tun network interface has been taken down.  Executed
              with the following parameters: <devicename> <ip address>

       --dynip net
              Dynamic IP address pool. Specifies a pool of dynamic IP addresses. If  this  option
              is omitted the network address specified by the --net option is used for dynamic IP
              address allocation.

       --pcodns1 host
              PCO DNS Server 1  (default  =  0.0.0.0).  PCO  stands  for  Protocol  Configuration
              options, and is part of the GPRS protocols. It is used to inform the mobile station
              about the DNS address to use for host name resolution.

       --pcodns2 host
              PCO DNS Server 2  (default  =  0.0.0.0).  PCO  stands  for  Protocol  Configuration
              options, and is part of the GPRS protocols. It is used to inform the mobile station
              about the DNS address to use for host name resolution.

       --timelimit seconds
              Exit ggsn after seconds. Used for debugging.

FILES

       /etc/ggsn.conf
              The configuration file for ggsn.
       /var/run/ggsn.pid
              Process ID file.
       /var/lib/ggsn
              Directory holding nonvolatile data.

BUGS

       Report all bugs to the OpenGGSN bug tracking list at http://sourceforge.net/projects/ggsn/

       ggsn has very  limited  management  support.  Currently  both  SNMP  as  well  as  billing
       mechanisms are missing.

SEE ALSO

       sgsnemu(8)

NOTES

       Besides  the  long options documented in this man page ggsn also accepts a number of short
       options with the same functionality. Use ggsn --help for a full list of all the  available
       options.

       The TUN/TAP driver is required for proper operation of ggsn.  For linux kernels later than
       2.4.7 the TUN/TAP driver is included in the kernel,  but  typically  needs  to  be  loaded
       manually  with  modprobe  tun.  For automatic loading the line alias char-major-10-200 tun
       can    be     added     to     /etc/modules.conf.      For     other     platforms     see
       http://vtun.sourceforge.net/tun/  for  information on how to install and configure the tun
       driver.

       ggsn uses the  GPRS  Tunneling  Protocol  (GTP)  as  specified  by  the  Third  Generation
       Partnership   Project   (3GPP).   3GPP   protocols   specifications   can   be   found  at
       http://www.3gpp.org

COPYRIGHT

       Copyright (C) 2002, 2003 by Mondru AB.

       The contents of this file may be used under the terms of the GNU  General  Public  License
       Version 2, provided that the above copyright notice and this permission notice is included
       in all copies or substantial portions of the software.

AUTHORS

       Jens Jakobsen <jj@openggsn.org>

                                            July 2003                                     ggsn(8)