# GGSN Configuration Parameters

The table displays following information:

> T3-Tunnel Timer (cgprsGtpT3TunnelTimer)

> T3-Response Timer (cgprsGtpT3ResponseTimer)

> N3-Requests (cgprsGtpN3Request)

> N3-Buffer-Size (cgprsGtpN3BufferSize)

> Echo Request Timer (cgprsGtpEchoRequestTimer)

> Bandwidth Resource (cgprsGtpGSNTotalBandwidthResrc)

> PDP Contexts (cgprsGtpMaxNumPDPCxts)

> Monitor Duration (cgprsGtpDroppedPktsMonTime)

> GTP Echo Failed Trap Enable (cgprsGtpNoRespToEchoNotifEnable)

> Charging PDP Context Activation Rejection Trap Enable (cgprsGtpPDPCxtActRejNotifEnable)

### T3-Tunnel timer (cgprsGtpT3TunnelTimer)
(units: seconds)

T3 -Tunnel timer for mobility management.

The timer is started by old SGSN. When the timer is running, T-PDUs received by the old SGSN and any buffered T-PDUs are forwarded to the new SGSN.

### T3-Response Timer (cgprsGtpT3ResponseTimer)

T3 response timer of retransmission. When a signalling request is transmitted, the timer is started by GGSN.

T3 is used for messaged transmission when no response is received by the time the timer expires.

The total wait time must be shorter than the mobile system wait time between Retries of Attach and RA updates. The product of cgprsGtpT3ResponseTimer and cgprsGtpN3requests must be less than the minimum value of the Attach Timer (T3310) and the Routing Area update timer (T3330). The cgprsGtpT3ResponseTimer timer recommends an adaptive back-off mechanism, using increasing values, for example, 1,2,4, and 8 seconds.

### N3-Requests (cgprsGtpN3Request)

Indicates the maximum number of times a signalling request is retransmitted if no corresponding response is received.

### N3-Buffer-Size (cgprsGtpN3BufferSize)

Indicates the size, in bytes, of the receive buffer for G-PDUs and signalling request messages.

If the bytes in a received packet exceed the buffer capacity, the excess bytes are discarded.

### Echo Request Timer (cgprsGtpEchoRequestTimer )

Indicates the time to transmit request message. An echo response message is normally received in response to echo request message. If there is no response to the echo request, a notification identifies the peer GSN that fails to respond.

### Bandwidth Resource (cgprsGtpGSNTotalBandwidthResrc)

Indicates the total bandwidth resource in a GGSN.

### PDP Contexts (cgprsGtpMaxNumPDPCxts)

Indicates the maximum number of PDP contexts allowed.

The PDP context contains the session mangement parameters necessary to transfer between SGSNs at the Inter SGSN routing update procedure.

### Monitor Duration (cgprsGtpDroppedPktsMonTime)

Indicates the time, in seconds, allowed for monitoring the excessive rate at which packets are dropped by the GSN because of an unknown GTP header problem.

### GTP Echo Failed Trap Enable (cgprsGtpNoRespToEchoNotifEnable)

Indicates whether the system generates an echo failure notification. A false value prevents the CGPRS GTP GSN echo failed notification from being generated by the system.

### PDP Context Activation Rejection Trap Enable (cgprsGtpPDPCxtActRejNotifEnable)

Indicates whether the system produces the cgprsGtpPDPCxtActivationRejNotif. A false value prevents the cgprsGtpPDPCxtActivationRejNotif from being generated by this system.