** As of September 2017, OpenGGSN is obsoleted by OsmoGGSN, please use http://git.osmocom.org/osmo-ggsn/ instead**

OpenGGSN - Open Source GGSN

This repository contains a C-language implementation of a GGSN (Gateway GPRS Support Node), a core network element of ETSI/3GPP cellular networks such as GPRS, EDGE, UMTS or HSPA.

OpenGGSN is part of the Osmocom Open Source Mobile Communications projects, even thogh it was previously developed by Mondru AB.

** As of September 2017, OpenGGSN is obsoleted by OsmoGGSN, please use http://git.osmocom.org/osmo-ggsn/ instead**

Homepage

The official homepage of the project is https://osmocom.org/projects/openggsn/wiki

GIT Repository

** As of September 2017, OpenGGSN is obsoleted by OsmoGGSN, please use http://git.osmocom.org/osmo-ggsn/ instead**

Homepage You can clone from the official libosmocore.git repository using

git clone git://git.osmocom.org/openggsn.git

There is a cgit interface at http://git.osmocom.org/openggsn/

Documentation

There currently is no other documentation other than the wiki on the homepage. It would be great if somebody would work towards a user manual that can become part of the osmo-gsm-manuals project.

Mailing List

Discussions related to openggsn are happening on the osmocom-net-gprs@lists.osmocom.org mailing list, please see https://lists.osmocom.org/mailman/listinfo/osmocom-net-gprs for subscription options and the list archive.

Please observe the Osmocom Mailing List Rules when posting.

Contributing

Our coding standards are described at https://osmocom.org/projects/cellular-infrastructure/wiki/Coding_standards

We us a gerrit based patch submission/review process for managing contributions. Please see https://osmocom.org/projects/cellular-infrastructure/wiki/Gerrit for more details

The current patch queue for OpenGGSN can be seen at https://gerrit.osmocom.org/#/q/project:openggsn+status:open OPENGGSN README

QuickStart

Requirements

Linux OpenGGSN was originally developed and tested using Redhat 8.0 and 9.0 and is these days mostly developed on Debian GNU/Linux. It should run also on other Linux distributions as well as FreeBSD, but this is untested. Compilation on Solaris 2.8 has also been verified.

Tun The tun driver is required for proper operation of openggsn. For Linux kernels later than 2.4.7 the driver is typically included, but might need to be configured for automatic loading:

1. Add the following line to /etc/modules.conf: alias char-major-10-200 tun
2. depmod -a

Installation from binary

OpenGGSN is built for common versions of Debian and Ubuntu as part of the Osmocom Nightly Builds project. If you don't want to do development, it is suggested to simply use those binary packages, rather than building yourself from source.

Installation from source

1. ./configure
2. make
3. make install

You need to be root in order to install the package, but not in order to compile.

Running

sgsnemu Start the emulator as root using the command:

sgsnemu -l 10.0.0.50 -r 10.0.0.40 --createif --defaultroute

This will cause the sgsn emulator to bind to local address 10.0.0.50 and connect to the ggsn found at 10.0.0.40. It will first send off an ECHO_REQUEST message. After this it will attempt to establish a pdp context. If successful it will create a local interface and set up routing. Now you should be able to ping through the connection. Use a network analysator such as ethereal to monitor the traffic.

sgsnemu -h will show a list of available options.

sgsnemu -c sgsnemu.conf will use sgsnemu.conf as a configuration file. A sample file is provided in examples/sgsnemu.conf.

ggsn Edit the configuration file ggsn.conf found under openggsn/examples. Start the ggsn as root using the command:

ggsn --fg -c examples/ggsn.conf -l 10.0.0.40 --statedir ./

This will run the ggsn in foreground using the local interface 10.0.0.40. If you don't have a GSM network available for testing you can use sgsnemu to test the GGSN.

Support

Please contact the Mailing List above for community-based support.

Features

OpenGGSN is an open source implementation of GPRS Support Nodes (GSNs). It implements the GPRS tunneling protocol (GTP) version 0 and version 1.

OpenGGSN provides 3 components:

• gtplib
• ggsn
• sgsnemu

gtplib This library contains all functionality relating to the GTP protocol. Use this library if you want to implement your own GSN. gtplib supports both GTPv0 (GSM 09.60) and GTPv1 (3GPP 29.060). At the moment no interface documentation is available for download.

ggsn The ggsn implements a Gateway GPRS Support Node. The GGSN is a small application which is provided in order to test and demonstrate the use of gtplib. It is fully compliant to the 3GPP standards, but lacks important functionality such as charging and management. Use this application as a starting point if you want to build your own GGSN with your own fancy VPN, management and charging functionality.

sgsnemu This application emulates a Serving GPRS Support Node (SGSN). sgsnemu enables you to test your 3GPP core network without the need to invest in a 3G radio access network. An important application of sgsnemu is the testing of roaming connectivity through a GPRS roaming exchange. sgsnemu will first attempt to use GTPv1. If unsuccessful it will fallback to GTPv0.

Performance

Two experiments were performed in order to test the performance of sgsnemu and ggsn. The ggsn used a 550 MHz Athlon with 384 MB of RAM. sgsnemu used a 1 GHz Athlon with 256 MB of RAM. Both machines had 100 Mb/s NICs (RTL-8139) and were connected through a crossed patch cable. Both tests were performed by sending ICMP echo packets from sgsnemu to the ggsn.

89.5 Mb/s IP throughput when sending 10000 ICMP ping packets with a payload of 1400 bytes. Transfer time 1.27 sec, no packets lost.

71.4 Mb/s IP throughput when sending 10000 ICMP ping packets with a payload of 1000 bytes. Transfer time 1.15 sec, no packets lost.

12,1 Mb/s IP throughput when sending 10000 ICMP ping packets with a payload of 100 bytes. Transfer time 0.84 sec, no packets lost.

Required software

Tun

Both ggsn and sgsnemu uses the tun package. You need at least tun version 1.1. With Linux tun is normally included from kernel version 2.4.7. To configure automatic loading:

1. Add the following line to /etc/modules.conf: alias char-major-10-200 tun
2. depmod -a

Alternatively you can execute "modprobe tun" on the commandline.

For Solaris the tun driver needs to be installed manually. For general information about tun see http://vtun.sourceforge.net/tun/

Gengetopt

Gengetopt is required if you want to change the options defined in the cmdline.ggo source file. You need at least gengetopt version 2.8. If you are just going to compile the programs you don't need gengetopt.

To use gengetopt for the ggsn do the following: cd ggsn gengetopt < cmdline.ggo --conf-parser

To use gengetopt for the sgsnemu do the following: cd sgsnemu gengetopt < cmdline.ggo --conf-parser

For more information about gengetopt see http://www.gnu.org/software/gengetopt/gengetopt.html

Compilation and Installation

Setting up autotools

You do not need to perform this step if you are only going to compile the package:

1. Get version from somewhere: Script to extract version from configure.in
2. Copy the latest config.guess and config.sub from ftp://ftp.gnu.org/gnu/config
3. Run autoscan and copy configure.scan to configure.in
4. Add/edit the following lines in configure.in:
   • AC_INIT(openggsn, 0.70, jj@openggsn.org)
   • AC_CONFIG_SRCDIR([gtp/gtp.c])
   • AM_CONFIG_HEADER([config.h])
   • AC_PROG_LIBTOOL
   • AM_PROG_LIBTOOL
   • AM_INIT_AUTOMAKE()
5. libtoolize --automake --copy (ads copy of ltmain.sh)
6. aclocal
7. autoheader
8. automake --add-missing --copy (Ads copy of mkinstalldirs missing, install-sh, depcomp)
9. automake
10. autoconf

The above will initialise the project to the current version of autotools (As installed in RedHat 8.0). See http://sources.redhat.com/autobook/autobook/autobook_25.html#SEC25 for details on autotools.

Checking out from CVS

To download the latest source code from anonymous CVS:

cvs -d:pserver:anonymous@cvs.sourceforge.net:/cvsroot/ggsn login cvs -z3 -d:pserver:anonymous@cvs.sourceforge.net:/cvsroot/ggsn co openggsn

Or to download from developer CVS:

export CVS_RSH=ssh cvs -z3 -d:ext:developername@cvs.sourceforge.net:/cvsroot/ggsn co openggsn

Both the above sets of commands creates a new directory called openggsn.

Compilation and installation

If compiling under Solaris you need to edit the following line in ggsn/Makefile.in and sgsnemu/Makefile.in:

LDFLAGS = -Wl,--rpath -Wl,/usr/local/lib @EXEC_LDFLAGS@

should be changed to:

LDFLAGS = -lresolv -lsocket -lnsl @EXEC_LDFLAGS@

Note that the above is not necessary on other platforms. Compilation and installation is performed by the following steps:

1. ./configure
2. make clean
3. cd gtp
4. make
5. make install (as root)
6. cd .. (Step 3 to 6 you only need to run the first time to install libgtp)
7. make
8. make install (as root)
9. Add /usr/local/lib to /etc/ld.so.conf
10. run ldconfig

(Steps 9 and 10 are not required as path to libgtp is included in Makefile)

Documentation can be converted to html by issuing:

1. txt2html -pm -tf README > README.html
2. txt2html -pm -tf NEWS > NEWS.html
3. man2htm ggsn.8 > ggsn.html
4. man2htm sgsnemu.8 > sgsnemu.html

Installation from bi