Cisco Cisco ASR 5000 Technical Manual
In order to indicate the end of the overload situation, the MME sends an Overload Stop message to the eNB:
Note: The SGSN also has a similar mechanism for signaling reduction, which is mentioned in 3GPP TS
25.413.
25.413.
PGW Control of Overload
The PGW can reject a PDN connection during overload scenarios. The PGW can detect an overload condition
and start or stop overload control based on criteria such as:
and start or stop overload control based on criteria such as:
The maximum number of active bearers per APN
•
The maximum rate of bearer activations per APN
•
The PGW can specify a PGW back−off timer towards the MME for a specific APN, and the MME should
reject the PDN connection requests for that APN during this time period. The MME can select another PGW
instead of rejection during that time period, unless there is already a current PDN connection to the same APN
for that UE.
reject the PDN connection requests for that APN during this time period. The MME can select another PGW
instead of rejection during that time period, unless there is already a current PDN connection to the same APN
for that UE.
Note: The GGSN congestion control mechanism is similar to that on the PGW, which is mentioned in 3GPP
TS 23.060. The PGW congestion control mechanism is mentioned in 3GPP TS 23.401.
TS 23.060. The PGW congestion control mechanism is mentioned in 3GPP TS 23.401.