- Consider a network where the
home network
of the moble host:
- can be reached
through
two different routers
(Multiple entry points are used to provide better reliability - if one route is broken, the other route will keep you connected on the Internet)
Example:
Note:
- R1
is the
home agent
- Only the router R1 has the virtual forwarding entry !!!
- can be reached
through
two different routers
- Consider an
IP packet destined for
the
mobile host (10.0.0.4)
that arrives to the
home network
through
R2:
- Result:
- The router R2 will
detect that:
- IP destination is a local IP network
Graphically:
Therefore:
- The router R2 will send the IP packet using a physical frame !!!
- The router
R2 will
ARP
the destination 10.0.0.4
(to find its
physical (Ethernet/Wireless)
MAC address):
- We have a problem:
- The ARP request for
the mobile host 10.0.0.4
will not be answered:
- because mobile host 10.0.0.4 is not present in the 10.0.0.xx network !!!
- The ARP request for
the mobile host 10.0.0.4
will not be answered:
- The router R2 will
detect that: