Cisco PIX 500 Series Configuration Manual page 499

Chapter 25 Configuring Application Layer Protocol Inspection
b.
g. To allow GTP responses from any GSN in the network object representing the GSN pool, defined in
c., d, to the network object representing the SGSN, defined in c., f., enter the following commands:
hostname(config)# gtp-map map_name
hostname(config-gtp-map)# permit response to-object-group SGSN-name from-object-group
GSN-pool-name
For example, the following command permits GTP responses from any host in the object group
named gsnpool32 to the host in the object group named sgsn32:
hostname(config-gtp-map)# permit response to-object-group sgsn32 from-object-group
gsnpool32
The following example shows how to support GSN pooling by defining network objects for the GSN
pool and the SGSN. An entire Class C network is defined as the GSN pool but you can identify
multiple individual IP addresses, one per network-object command, instead of identifying whole
networks. The example then modifies a GTP map to permit responses from the GSN pool to the
SGSN.
hostname(config)# object-group network gsnpool32
hostname(config-network)# network-object 192.168.100.0 255.255.255.0
hostname(config)# object-group network sgsn32
hostname(config-network)# network-object host 192.168.50.100
hostname(config)# gtp-map gtp-policy
hostname(config-gtp-map)# permit response to-object-group sgsn32 from-object-group
gsnpool32
To specify the maximum number of GTP requests that will be queued waiting for a response, enter
h.
the following command:
hostname(config-gtp-map)# request-queue max_requests
where the max_requests argument sets the maximum number of GTP requests that will be queued
waiting for a response, from 1 to 4294967295. The default is 200.
When the limit has been reached and a new request arrives, the request that has been in the queue
for the longest time is removed. The Error Indication, the Version Not Supported and the SGSN
Context Acknowledge messages are not considered as requests and do not enter the request queue
to wait for a response.
To change the inactivity timers for a GTP session, enter the following command:
i.
hostname(config-gtp-map)# timeout {gsn | pdp-context | request | signaling | tunnel}
hh : mm : ss
Enter this command separately for each timeout.
The gsn keyword specifies the period of inactivity after which a GSN will be removed.
The pdp-context keyword specifies the maximum period of time allowed before beginning to
receive the PDP context.
OL-12172-03
hostname(config)# object-group network sgsn32
hostname(config-network)#
Use the network-object command with the host keyword to identify the SGSN.
hostname(config-network)# network-object host IP-address
For example, the following command creates a network objects representing the SGSN:
hostname(config-network)# network-object host 192.168.50.100
hostname(config-network)#
Cisco Security Appliance Command Line Configuration Guide
GTP Inspection
25-35