sgsnemu(8)

NAME

sgsnemu - Serving GPRS Support Node Emulator

SYNOPSIS

sgsnemu --help
sgsnemu --version
sgsnemu [ --debug ] [ --conf file ] [ --pidfile file  ]  [
--statedir  file  ]  [  --dns host ] [ --listen host ] [ --remote
host ] [ --contexts num ] [ --timelimit seconds ] [  --gtpversion
version  ]  [ --apn apn ] [ --selmode selmode ] [ --imsi imsi ] [
--nsapi nsapi ] [ --msisdn msisdn ] [ --qos qos  ]  [  --charging
charging ] [ --uid uid ] [ --pwd pwd ] [ --createif ] [ --net net
] [ --defaultroute ] [ --ipup script ]  [  --ipdown  script  ]  [
--pinghost  host  ]  [  --pingrate  num  ]  [  --pingsize num ] [
--pingcount num ]

DESCRIPTION

sgsnemu is part of the OpenGGSN project, and implements a

Serving GPRS Support Node (SGSN) emulator. It can be used for

testing Gateway GPRS Support Nodes (GGSNs), GPRS core networks as

well as GPRS roaming connections.

The GPRS functionality and protocols has been standardised

by the Third Generation Partnership Project (3GPP). According to

the 3GPP specifications an SGSN has several interfaces. sgsnemu

implements the Gn/Gp interface which is used towards GGSNs.

The Gn/Gp interface can be seen as the uplink interface of

the SGSN. It is used for communicating with a GGSN which is typi

cally connected to the Internet. 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.

sgsnemu will establish a number of connections to the

GGSN. An internal ping facility will transmit ping requests

through the established connections. Alternatively a local net

work interface can be created. In this case sgsnemu will forward

packets between the local network interface and the established

connections on the Gn/Gp interface.

sgsnemu uses the TUN/TAP driver for the local interface. A

tun network interface is established for each connection estab

lished to the GGSN.

Runtime errors are reported using the syslogd (8) facili

ty.

OPTIONS

--help Print help and exit.

--version

Print version and exit.

--debug

Run in debug mode (default = off)

--conf file

Read configuration file where each line corresponds

to one command line option, but with the leading '--' removed.

Command line options override the options given in the configura

tion file.

--pidfile file

Filename of process id file (default = ./sgsne

mu.pid)

--statedir path

path to directory of nonvolatile data (default =

./)

--dns host

DNS server to use for APN lookups. If omitted the

default system DNS configuration will be used.

--listen host

Local interface IP address to use for the Gn/Gp in

terface. If omitted sgsnemu will listen to any IP address.

--remote host

GGSN host to connect to. If DNS is setup correctly

it should be possible to specify the access point name (APN) as

the remote host.

--contexts num

Number of contexts to establish. (default = 1). For

multiple contexts the the first context is established using imsi

+ 0 and msisdn + 0. The second context is established using imsi

+ 1 and msisdn + 1. The third....

--timelimit seconds

Exit sgsnemu after seconds. When using the ping

facility sgsnemu will also exit after --pingcount packets has

been transmitted.

--gtpversion version

version of GTP to use when establishing a context

(default = 1). If not able to establish a GTPv1 context sgsnemu

will fall back to using GTPv0.

--apn apn

apn to use when connecting to the GGSN (default =

internet). APN is an abbreviation of Access Point Name.

--selmode selmode

Selection mode to use when connecting to the GGSN

(default = 0x01). The encoding of the selection mode is as fol

lows: 0: MS or network provided APN, subscribed verified, 1: MS

provided APN, subscription not verified, 2: Network provided APN,

subscription not verified.

--imsi imsi

imsi to use when connecting to the GGSN (default =

240010123456789). IMSI is an abbreviation of International Mobile

Subscriber Identity. Must be exactly 15 digits. See the contexts

option for the the use of the imsi option with multiple contexts.

--nsapi nsapi

nsapi to use when connecting to the GGSN (default =

0). Must be between 0 and 15.

--msisdn msisdn

msisdn to use when connecting to the GGSN (default

= 46702123456). MSISDN is an abbreviation of International Mobile

Integrated Services Digital Network. Effectly a phone number in

international format without the leading 00 or 011. See the

contexts option for the the use of the msisdn option with multi

ple contexts.

--qos qos

qos to use when connecting to the GGSN (default =

0x0b921f). QoS is an abbreviation of Quality of Service. See 3GPP

specification 09.60 for the format of this string.

--charging charging

Charging characteristics to use when connecting to

the GGSN (default = 0x0800). 0x0800 = Normal, 0x0400 = Prepaid,

0x0200 = Flat rate, 0x0100 = Hot billing. See 3GPP specification

32.015 for the format of this field.

--uid uid

User ID to send to GGSN as protocol configuration

option.

--pwd pws

Password to send to GGSN as protocol configuration

option.

--createif

Create a local tun interface. This interface will

be used for forwarding packets to and from the Gn/Gp interface.

Use with caution as the Gn/Gp interface is normally be routed to

the Internet by the GGSN. Only one interface will be created,

even if several contexts are established. The interface will be

given an IP address for each established context, or the address

can be specified with the net option.

--net net

Network address of the local interface. The net op

tion is only valid when the createif option is used. The net op

tion is given in cidr format (net/mask bits). If the net option

omitted an IP address is allocated for each context established.

--defaultroute

Create a defaultroute to the local tun interface.

--ipup script

Script executed after the tun network interface has

been brought up. Executed with the following parameters: <devi

cename> <ip address>

--ipdown script

Script executed after the tun network interface has

been taken down. Executed with the following parameters: <devi

cename> <ip address>

--pinghost host

Ping host through the Gn/GP interface. Ping statis

tics are reported much like done by the original ping program.

Use this facility for performance test of GGSNs.

--pingrate num

Number of ping requests per second (default = 1)

--pingsize num

The size of each ping requests in octets (default =

56)

--pingcount num

Number of ping requests to send (default = 0). A

value of 0 (zero) indicates infinite.

--pingquiet

Do not print information for each packet received

(default = off). Is quite usefull for high pingrates.

FILES

sgsnemu.conf

The configuration file for sgsnemu.

.sgsnemu.pid

Process ID file.

./

Directory holding nonvolatile data.

BUGS

Report all bugs to the OpenGGSN bug tracking list at

http://sourceforge.net/projects/sgsnemu/

SEE ALSO

ggsn(8), syslog(8)

NOTES

Besides the long options documented in this man page

sgsnemu also accepts a number of short options with the same

functionality. Use sgsnemu --help for a full list of all the

available options.

The TUN/TAP driver is required for proper operation of

sgsnemu. For linux kernels later than 2.4.7 the TUN/TAP driver

is included in the kernel, but typically needs to be loaded manu

ally 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 informa

tion on how to install and configure the tun driver.

sgsnemu uses the GPRS Tunneling Protocol (GTP) as speci

fied by the Third Generation Partnership Project (3GPP). 3GPP

protocols specifications can be found at http://www.3gpp.org

COPYRIGHT

Copyright (C) 2002, 2003, 2004 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>

May 2004

sgsnemu(8)