Packet Walk-Throughs
9-6
8000-A2-GB21-20
November 1997
7. From the routing table, the 8546 DSL card determines that 135.1.3.4 is
directly connected over s1c (one of the 8546 DSL card’s DSL ports).
8. The 8546 DSL card then forwards the ping to the RTU over s1c.
The HotWire RTU then issues a ping reply to IP address 135.1.1.1.
1. The RTU forwards the ping reply to the 8546 DSL card.
2. The 8546 DSL card consults its routing table to identify how to forward the
reply. Route #2 is used because the destination address (135.1.1.1) is the
135.1.1 subnet. Therefore, the next-hop address is the MCC card’s
s1b
interface (135.1.3.1).
3. Similarly, upon receiving the packet, the MCC card consults its routing table
to identify how to forward the packet. Since the destination IP address of the
ping is WS1 (135.1.1.1) and this does not match any entry in the route table,
the next-hop IP address (135.1.2.1) of the default route is used.
4. The MCC card then forwards the packet to its 10BaseT interface to the
router.
5. The router forwards the packet toward WS1 by normal means.
