Cisco Cisco Packet Data Interworking Function (PDIF) Documentation Roadmaps
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HA Overview
▀ Network Deployment Configurations
▄ Cisco ASR 5000 Series Product Overview
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Figure 120. Mobile IP, FA and HA Tunneling/Transport Methods.
How Mobile IP Works
As described earlier, Mobile IP uses three basic communications protocols; PPP, IP, and Tunneled IP in the form of IP-
in-IP or GRE tunnels. The following figure depicts where each of these protocols are used in a basic Mobile IP call.
in-IP or GRE tunnels. The following figure depicts where each of these protocols are used in a basic Mobile IP call.