# GGSN System Information (Contd)

1. Right click on the MWAM Card and select Configure.

2. Select category MWAM module.

3. Select a row and click the Configure button.

4. Select category GGSN System Information (contd.)

The following information appears:

> > Threshold Memory (cGgsnMemoryThreshold)

> > Service Mode (cGgsnServiceMode)

> > Session Timeout Value (cGgsnSessionTimeout)

> > Throughput Interval ONE (cGgsnThruputIntervalOne)

> > Throughput Interval TWO (cGgsnThruputIntervalTwo)

> > GGSN Compliance Level (cGgsnCompliance3GppGgsn)

> > Create Existing PDP as Update (cGgsnCreateReqV1UpdExistPdp)

> > Turn on Attribute 27 Session Timeout (cGgsnRadAttrSessTimeout)

> > Disable Verify-MS in Downlink (cGgsnDownlinkVerifyMsDisable)

> > Service Mode Status (cGgsnServiceModeStatus)

> GGSN Global Error Notification (cGgsnGlobalErrorNotifEnabled)

> GGSN Access Point Notification (cGgsnAccessPointNotifEnabled)

> GGSN PacketData Protocol Notification (cGgsnPdpNotifEnabled)

> GTP SLB Mode (cGgsnSlbMode)

> CAC Failure Notification (cGgsnSlbNotif)

> ### Threshold Memory (cGgsnMemoryThreshold)

> Gateway GPRS Support Node (GGSN) memory overload protection is a mechanism to prevent GGSN from completely running out of memory when GGSN is running near its capacity, or in some failure scenarios such as content gateway down. A protection mechanism is place; when the available memory on the GGSN drops below a configured threshold the following occurs:

> - Charging triggers are ignored.
> - PDP create is rejected.
> - PDP update requests will delete PDP,.

> Charging triggers occur due to criteria such as volume limit and time limit. When one of the conditions is met , the Charging Data Records (CDRs) are closed and will be updated to the charging gateway.

> ### Service Mode (cGgsnServiceMode)

> GGSN supports this General Packet Radio Service (GPRS) service mode for maintenance purposes. Two modes are supported in GGSN, operational and maintenance mode. 'inService' mode represents nominal operation, and there will be no change in the way the GGSN operates. The following is true of 'maintenance' mode:

> - Imposes restrictions, such as some of the configurations allowed by the GGSN, and no new PDPs accepted.
> - Can be useful to make some changes to the configuration of the GGSN without affecting the existing PDPs.
> - Applies globally to the GGSN, which means the whole box will be put in maintenance mode.

> Additional maintenance modes--that are outside the scope of this MIB--exist:

> - APN level maintenance mode--Defined in CISCO-GPRS_ACC-PT-MIB
> - Charging maintenance mode--Defined in CISCO-GPRS-CHARGING-MIB

> Internally, GGSN maintains three states (inService, maintenance, and outOfService ), which can be viewed with cGgsnServiceModeStatus.

> The SNMP entity generates notification when switching modes and uses the cGgsnInServiceNotif and cGgsnMaintenanceNotif for this purpose.

> ### Session Timeout Value (cGgsnSessionTimeout)

> PDP context timeout value. The PDP context terminates after this timer expires. This value has meaning when cGgsnRadAttrSessTimeout is set to 'true' and if the attribute #27 is not received from the AAA.

> ### Throughput Interval ONE (cGgsnThruputIntervalOne)

> This object and cGgsnThruputIntervalTwo specify the interval at which the data throughput needs to be collected per Access Point Name (APN)/Serving GPRS support Node (SGSN). After this object is set to a valid value, data throughput collection starts for per configured APN and per PATH created. Data throughput collection is updated periodically (each time the configured throughput interval expires) to the corresponding objects (cGgsnSgsnStatTable for per SGSN and cgprsAccPtThruputStatsTable for per APN).

> When set to zero (0), collection for this interval is stopped and the data related to this interval is deleted from the tables (cGgsnSgsnStatTable and cgprsAccPtThruputStatsTable).

> INCONSISTENT value SNMP error happens when trying to set cGgsnThruputIntervalOne and cGgsnThruputIntervalTwo with same value (except when that value is zero (0)). Setting the same value to the same object resets the value / collection status for that interval.

> ### Throughput Interval TWO (cGgsnThruputIntervalTwo)

> This object and cGgsnThruputIntervalTwo specify the interval at which the data throughput needs to be collected per APN/SGSN.

> After this object is set to some valid value, data throughput collection starts for per configured APN and per PATH created. The data throughput collection is updated periodically (each expiry of configured throughput interval) to the corresponding objects (cGgsnSgsnStatTable for per SGSN and cgprsAccPtThruputStatsTable for per APN).

> When set to zero (0), collection for this interval is stopped and the data related to this interval is deleted from the tables (cGgsnSgsnStatTable and cgprsAccPtThruputStatsTable).

> INCONSISTENT value SNMP error happens when trying to set cGgsnThruputIntervalOne and cGgsnThruputIntervalTwo with same value (except when that value is zero (0)). Setting the same value to the same object resets the value / collection status for that interval.

> ### GGSN Compliance Level (cGgsnCompliance3GppGgsn)

> Compliance level for the particular GGSN version present in cGgsnVersion--This object can be used to set the compliance level back to the previous GGSN version. When set to 'default', the compliance level for that GGSN version, indicated by the object cGgsnVersion, will be considered.

> When the cGgsnVersion is holding a value of 'release50', the compliance level can be set back to 'release40'.

> ### Create Existing PDP as Update (cGgsnCreateReqV1UpdExistPdp)

> This object is used for backward compatibility due to implementation of CR 311 (Release 5).

> CR 311: The SGSN shall not send a Create PDP Context Request for an already active context. If a new Create PDP Context Request is incoming on TEID 0 for an already active PDP context, this Create PDP Context Request must be considered related to a new session.

> The existing PDP context shall be torn down locally, and the associated PDP contexts deleted locally, before the new session is created. If a new Create PDP Context Request is incoming on a TEID that is different from 0 and this TEID is already allocated to one or more activated PDP contexts, and the NSAPI IE value in this message matches the NSAPI value of an active PDP context, the GGSN shall send back a Create PDP Context Response with a rejection cause code. The decision to teardown or keep the existing PDP context is implementation-dependent:

> - false--The changes due to CR 311 will be applicable.
> - true--The changes due to CR 311 will not be taken into account.

> This object has no meaning when the object cGgsnCompliance3GppGgsn holds a value of 'release40'.

> ### Turn on Attribute 27 Session Timeout (cGgsnRadAttrSessTimeout)

> This object is used for enabling the session timeout feature on the global (router) level set using cGgsnSessionTimeout, APN level (cgprsAccPtAbsoluteSessionTimer, which is defined in CISCO-GPRS-ACC-PT-MIB and is outside the scope of this MIB). This object is also used to parse the RADIUS attribute #27 present in the access-accept request:

> - true- -Session timeout is enabled.
> - false- Session timeout is disabled.

> ### Disable Verify-MS in Downlink (cGgsnDownlinkVerifyMsDisable)

> This object enables the feature that will allow the GGSN to route IP packets beyond the mobile station. This works only if a static route is added in GGSN to the node beyond the mobile station. On enabling this feature, GGSN will route the packets in both process switch path and cef switch path. This is supported only for IP PDP type.

> This feature has some limitations:

> - Not scalable, since the operator has to add static route to all nodes beyond the mobile station.
> - Only works for mobile stations having static addresses.
> - In case of GTPv1 the mobile station has to select TFT's to allow traffic flow in the downlink direction.
> - IP address assignment/Radius for the devices behind the mobile station needs to be done within the scope of that network; the GGSN will not provide this facility in any way for the hosts behind the mobile station.
> - In a MWAM and Cat6500/7600 environment, the static route should be added only on that particular GGSN on the MWAM from where the mobile station is reachable.

> When set to:

> - true-- Routing beyond the mobile station is enabled.
> - false-- Routing beyond the mobile station is disabled.

> ### Service Mode Status (cGgsnServiceModeStatus)

Represents the internal service mode that GSN maintains. The service switching is done with object cGgsnServiceMode.

### GGSN Global Error Notification (cGgsnGlobalErrorNotifEnabled)

Indicates whether cGgsnGlobalErrorNotif notification will be sent when a notification is generated by the device. When set to:

- true--enables the device to send a notification.
- false-- prevents the device from sending out a notification.

Note: This object is available for GGSN version 6.0 and later.

### GGSN Access Point Notification (cGgsnAccessPointNotifEnabled)

Indicates whether cGgsnAccessPointNameNotif notification will be sent when a notification is generated by the device. When set to:

- true--enables the device to send a notification.
- false-- prevents the device from sending out a notification.

Note: This object is available for GGSN version 6.0 and later.

### GGSN PacketData Protocol Notification (cGgsnPdpNotifEnabled)

Indicates whether cGgsnPacketDataProtocolNotif notification will be sent when a notification is generated by the device. When set to:

- true--enables the device to send a notification.
- false--prevents the device from sending out a notification.

Note: This object is available for GGSN version 6.0 and later.

### GTP SLB Mode (cGgsnSlbMode)

GTP SLB can operate in two modes: dispatched and directed:

- dispatched mode--Forwards the create request without changing the destination IP address (vserver address) and the create response comes from the same (vserver) address.
- directed mode--Changes the destination IP address to that of GGSN's VT and the create response comes from the GGSN VT.

Note: This object is available for GGSN version 6.0 and later.

### CAC Failure Notification (cGgsnSlbNotif)

This object is used to enable or disable the GGSN behavior of sending CAC failure notification to SLB, or session failure notification to SLB.

When set to:

- cacFailure(1)--This object is required to enable the feature in the dispatched mode of operation of SLB.
- sessionDeletion(2)--GGSN will send delete notification message to SLB when the last PDP associated with an IMSI is deleted.

Note: This object is available for GGSN version 6.0 and later.