User`s guide

IP Routing
6-4
8000-A2-GB21-10
June 1997
DSL Card Static Route Example
The following illustration shows an example of how static routes configured on a
DSL card are used in its routing table:
97-15471-01
Router
155.1.2.1/16
155.1.3.1/24
ISP
155.1.2.2/16
DSL Card
155.1.3.2/16
RTU
135.1.3.3
MCC Card
135.1.3.1/16
135.1.2.2/16
Unnumbered
DSL
Interface
ES
155.1.3.4
Host/Net/Subnet
1) 155.1.3.4
2) 135.1.1.1
3) 0.0.0.0
Subnet Mask
255.255.255.255
255.255.255.0
0.0.0.0
Next-Hop Address
135.1.3.3
135.1.3.1
155.1.3.1
S/D (Source/Destination)
dst (destination)
dst (destination)
dst (destination)
DSL Routing Table
In this example:
 The DSL card’s Ethernet port is connected to the router’s port having an IP
address of 155.1.3.1.
Packets being routed in the upstream direction (to an ISP) would use the
third routing table entry, i.e.,
Host/Net/Subnet IP address 0.0.0.0 (by
definition) and a
Next Hop address of 155.1.3.1.
They would use this route because no other destination would match.
 The management domain IP address of the RTU is 135.1.3.3 and the IP
address of the ES is 155.1.3.4. Packets being routed downstream use the
first routing table entry, i.e.,
Host/Net/Subnet IP address of 155.1.3.4 and a
Next Hop address of 135.1.3.3. Note that this is a host route.
 The second routing table entry is for upstream routing to the NMS via the
MCC card. Note that this is a subnet route.