Cisco Cisco Packet Data Gateway (PDG)
SaMOG Gateway Overview
▀ SaMOG Services
▄ SaMOG Administration Guide, StarOS Release 18
22
The operator policy provides mechanisms to fine tune the behavior of subsets of subscribers above and beyond the
behaviors described in the user profile. It also can be used to control the behavior of visiting subscribers in roaming
scenarios, enforcing roaming agreements and providing a measure of local protection against foreign subscribers.
behaviors described in the user profile. It also can be used to control the behavior of visiting subscribers in roaming
scenarios, enforcing roaming agreements and providing a measure of local protection against foreign subscribers.
An operator policy associates APNs, APN profiles, an APN remap table, and a call-control profile to ranges of IMSIs.
These profiles and tables are created and defined within their own configuration modes to generate sets of rules and
instructions that can be reused and assigned to multiple policies. In this manner, an operator policy manages the
application of rules governing the services, facilities, and privileges available to subscribers. These policies can override
standard behaviors and provide mechanisms for an operator to get around the limitations of other infrastructure
elements, such as DNS servers and HSSs.
These profiles and tables are created and defined within their own configuration modes to generate sets of rules and
instructions that can be reused and assigned to multiple policies. In this manner, an operator policy manages the
application of rules governing the services, facilities, and privileges available to subscribers. These policies can override
standard behaviors and provide mechanisms for an operator to get around the limitations of other infrastructure
elements, such as DNS servers and HSSs.
The operator policy configuration to be applied to a subscriber is selected on the basis of the selection criteria in the
subscriber mapping at attach time. A maximum of 1,024 operator policies can be configured. If a UE was associated
with a specific operator policy and that policy is deleted, the next time the UE attempts to access the policy, it will
attempt to find another policy with which to be associated.
subscriber mapping at attach time. A maximum of 1,024 operator policies can be configured. If a UE was associated
with a specific operator policy and that policy is deleted, the next time the UE attempts to access the policy, it will
attempt to find another policy with which to be associated.
A default operator policy can be configured and applied to all subscribers that do not match any of the per-PLMN or
IMSI range policies.
IMSI range policies.
Changes to the operator policy take effect when the subscriber re-attaches and subsequent EPS Bearer activations.
P-GW Selection—MRME
The P-GW selection function enables the SaMOG Gateway's MRME service to allocate a P-GW to provide PDN
connectivity to the WLAN UEs in the trusted non-3GPP IP access network. The P-GW selection function can employ
either static or dynamic selection.
connectivity to the WLAN UEs in the trusted non-3GPP IP access network. The P-GW selection function can employ
either static or dynamic selection.
Static Selection
The PDN-GW-Allocation-Type AVP indicates whether the P-GW address is statically allocated or dynamically selected
by other nodes, and is considered only if MIP6-Agent-Info is present. When the PDN-GW-Allocation-Type AVP is
absent or is STATIC, and an initial attach occurs, or is DYNAMIC and a handoff attach occurs, the MRME service
performs static selection of the P-GW.
by other nodes, and is considered only if MIP6-Agent-Info is present. When the PDN-GW-Allocation-Type AVP is
absent or is STATIC, and an initial attach occurs, or is DYNAMIC and a handoff attach occurs, the MRME service
performs static selection of the P-GW.
The figure below shows the message exchange for static selection. The table that follows the figure describes each step
in the flow.
in the flow.
Figure 2. P-GW Static Selection
Table 1. P-GW Static Selection
Step
Description