Cisco Cisco ASR 5500

 

▄  HSGW Administration Guide, StarOS Release 18 

The rules discussed in this section pertain to the Ethernet 10/100 line card, the Ethernet 1000 line card and the four-port 
Quad Gig-E line card and the type of interfaces they facilitate, regardless of the application. 

The following engineering rules apply to the A10/A11 interface: 



 

An A10/A11 interface is created once the IP address of a logical interface is bound to an HSGW service. 



 

The logical interface(s) that will be used to facilitate the A10/A11 interface(s) must be configured within an 

“ingress” context. 



 

HSGW services must be configured within an “ingress” context. 



 

At least one HSGW service must be bound to each interface; however, multiple HSGW services can be bound to 

a single interface if secondary addresses are assigned to the interface. 



 

Each HSGW service must be configured with the Security Parameter Index (SPI) of the Evolved Packet Control 

Function (ePCF) that it will be communicating with over the A10/A11 interface. 



 

Multiple SPIs can be configured within the HSGW service to allow communications with multiple ePCFs over 

the A10/A11 interface. It is best to define SPIs using a netmask to specify a range of addresses rather than 
entering separate SPIs. This assumes that the network is physically designed to allow this communication. 



 

Depending on the services offered to the subscriber, the number of sessions facilitated by the A10/A11 interface 

can be limited. 

This section describes the engineering rules for the S2a interface for communications between the Mobility Access 
Gateway (MAG) service residing on the HSGW and the Local Mobility Anchor (LMA) service residing on the P-GW. 

The following engineering rules apply to the S2a interface from the MAG service to the LMA service residing on the P-
GW: 



 

An S2a interface is created once the IP address of a logical interface is bound to an MAG service. 

 For releases 15.0 and earlier, mag-service can only bind with IPv6 address. For releases 

16.0 and forward, mag-service is capable of binding with IPv6 and IPv4 interfaces. 



 

The logical interface(s) that will be used to facilitate the S2a interface(s) must be configured within the egress context. 



 

MAG services must be configured within the egress context. 



 

MAG services must be associated with an HSGW service. 



 

Depending on the services offered to the subscriber, the number of sessions facilitated by the S2a interface can be limited.