Cisco Cisco ASR 5000
APN Restriction
How it Works ▀
SGSN Administration Guide, StarOS Release 18 ▄
How it Works
During default bearer activation the Gn/S4-SGSN sends the current Maximum APN Restriction value for the UE to the
GGSN/ P-GW in the Create PDP Context Request/ Create Session Request (if it is the first activation for that UE or if
the APN Restriction is disabled, Maximum APN restriction will be "0" in the Create PDP Context Request/ Create
Session Request). The GGSN/P-GW has an APN restriction value for each APN. If the Maximum APN Restriction for
the subscriber is received in the Create PDP Context Request/ Create Session Request and APN Restriction value of the
APN to which activation is being requested do not concur then the GGSN/P-GW rejects the activation by sending a
Create PDP Context / Create Session Response failure message to the G/S4-SGSN with EGTP cause
"EGTP_CAUSE_INCOMPATIBLE_APN_REST_TYPE (0x68)".
GGSN/ P-GW in the Create PDP Context Request/ Create Session Request (if it is the first activation for that UE or if
the APN Restriction is disabled, Maximum APN restriction will be "0" in the Create PDP Context Request/ Create
Session Request). The GGSN/P-GW has an APN restriction value for each APN. If the Maximum APN Restriction for
the subscriber is received in the Create PDP Context Request/ Create Session Request and APN Restriction value of the
APN to which activation is being requested do not concur then the GGSN/P-GW rejects the activation by sending a
Create PDP Context / Create Session Response failure message to the G/S4-SGSN with EGTP cause
"EGTP_CAUSE_INCOMPATIBLE_APN_REST_TYPE (0x68)".
If the Maximum APN Restriction of the subscriber and APN Restriction of the APN to which activation is ongoing
agree as per APN Restriction rules, the GGSN/P-GW sends the APN Restriction value of the APN in the Create PDP
Context / Create Session Response as success during activation. The Gn/S4-SGSN updates the APN restriction value of
that PDN connection with the value received from GGSN/P-GW in the Create PDP Context/ Create Session Response.
The APN restriction value can be received by a new SGSN through context response and forward re-location request
messages.
agree as per APN Restriction rules, the GGSN/P-GW sends the APN Restriction value of the APN in the Create PDP
Context / Create Session Response as success during activation. The Gn/S4-SGSN updates the APN restriction value of
that PDN connection with the value received from GGSN/P-GW in the Create PDP Context/ Create Session Response.
The APN restriction value can be received by a new SGSN through context response and forward re-location request
messages.
The combination of APN Restriction values of all the PDN connections of a particular UE should be valid and the
maximum APN restriction value of the UE should be updated whenever the APN restriction value of a PDN connection
is updated.
maximum APN restriction value of the UE should be updated whenever the APN restriction value of a PDN connection
is updated.
Table below displays the valid combinations of APN restriction values:
Table 13. APN restriction values
Maximum APN Restriction
Value
Value
Type of
APN
APN
Application Example
APN Restriction Value allowed to be
established
established
0
No Existing Contexts or Restriction
All
1
Public-1
WAP or MMS
1, 2, 3
2
Public-2
Internet or PSPDN
1, 2
3
Private-1
Corporate (for example MMS
subscribers)
subscribers)
1
4
Private-2
Corporate (for example non-MMS
subscribers)
subscribers)
None
The valid combination of APN restriction values is achieved in the Gn/ S4-SGSN based on the APN restriction value of
the most restrictive PDN connection. If the bearer with the most restrictive APN restriction value gets de-activated, the
maximum APN restriction value is re-calculated from among the remaining active default bearers.
the most restrictive PDN connection. If the bearer with the most restrictive APN restriction value gets de-activated, the
maximum APN restriction value is re-calculated from among the remaining active default bearers.
In the Create PDP Context /Create Session Request during default bearer activation, the Gn/S4-SGSN sends the
Maximum APN Restriction Value for the UE. If no value is available (if this default bearer is the first activation) then,
the Maximum APN restriction value will be "0" in Create Session Request. A value of "0" in the Create PDP Context /
Create Session Request for Maximum APN restriction indicates there are no other existing PDN connections for the UE
or APN restriction is disabled.
Maximum APN Restriction Value for the UE. If no value is available (if this default bearer is the first activation) then,
the Maximum APN restriction value will be "0" in Create Session Request. A value of "0" in the Create PDP Context /
Create Session Request for Maximum APN restriction indicates there are no other existing PDN connections for the UE
or APN restriction is disabled.
If the APN restriction value received in the Create PDP Context / Create Session Response during activation violates the
current Maximum APN restriction, then the SGSN rejects the activation and also de-activates any other PDN connection
to the same APN. The SGSN considers the APN restriction received in latest Create PDP Context / Create Session
current Maximum APN restriction, then the SGSN rejects the activation and also de-activates any other PDN connection
to the same APN. The SGSN considers the APN restriction received in latest Create PDP Context / Create Session