SR OS TPSDA supports hybrid access deployments where a PGW acts as a HAG. In this model, both the fixed access and wireless access links share the same Layer 3 IP/IPv6 address. The RG/HAG determines which Layer 2 connection should be used. To support this model, SR OS IPoE session and PPPoE session functionality is extended to connect to a GTP uplink. When this uplink is active, all unicast traffic is forwarded by a GTP tunnel between the BNG and PGW. This way, the PGW acts as the Layer 3 gateway and the BNG does not attract subscriber traffic by regular routing. Multicast traffic is not supported and should be handled out-of-band.
Figure: Sample hybrid access deployment shows a sample Hybrid Access deployment with a PGW-based HAG.
For more details on GTP uplinks, see the GTP section.