Cisco Cisco Packet Data Gateway (PDG)

 

▄  SaMOG Administration Guide, StarOS Release 18 

 

 

4. 

The UE sends the IPv6 ICMPv6 Router Solicitation (ICMPv6 Type 133) message to the destination as "Link-Local Scope 
multicast All Routers Address (ff02:2)" with the source address as UEs Link-Local address. The UE also includes the 
ICMPv6 option "source link-layer address", which is the MAC address of the UE. 

5. 

The WLC starts PMIPv6 procedures when any of the following triggers occur: 



 

When an Access-Accept message is received from SaMOG and authentication is completed with the UE (Step 3). 



 

When an IPv6 Router Solicitation message is received from the UE. 

For IPv6 Support, the WLC sends the PMIPv6 PBU towards SaMOG by including the Home Network Prefix: "::" and Link 
Local Address: "::". 

6. 

SaMOG processes the received PMIPv6 PBU and responds with a PMIPv6 PBA, by including the valid Home Network 
Prefix and Link Local Address provided by the P-GW during S2a procedures. SaMOG also includes the IPv6 DNS 
Primary/Secondary addresses in the PMIPv6 PBA message.  
SaMOG provides the DNS parameters in the PBA only when the WLC requests for it in the PBU. 

   

7. 

The WLC processes the received ICMPv6 Router Solicitation message over the CAP-WAP Tunnel and responds with an 
ICMPv6 Router Advertisement (ICMPv6 Type 134) message over CAP-WAP Tunnel towards the UE. 
The WLC also includes the RDNSS, DNSSL options as per RFC 6106. 

8. 

The WLC may optionally send the Unsolicited IPv6 Router Advertisement (RA) over CAP-WAP Tunnel based on the local 
configuration. The IPv6 options included would be same as in Step 7. 

  For PMIPv6 access type, SaMOG silently drops unsolicited RA packets received from the 

WLC. 

9. 

The WLC receives the DHPCv6 Information-Request message over the CAP-WAP tunnel to fetch the configuration 
parameters based on the UE's behavior by including the Client-identifier and Option Request option with "DNS Recursive 
Name Server and "Domain Search List". 

10. 

The WLC responds with a DHCPv6 Reply over the CAP-WAP Tunnel by including the "DNS Recursive Name Server" 
and "Domain Search List". 

11. 

SaMOG acts as an Accounting proxy between WLC and Radius Accounting Server where all Accounting messages will 
have "Framed-IPv6-Prefix" AVP. 

 

The figure below shows the message flow to delegate an IPv6 prefix to the user equipment (UE) using stateful DHCPv6 
for a PMIPv6 access type.The table that follows the figure describes each step in the message flow.