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Cisco ONS 15454 Installation and Operations Guide
November 2001
Chapter4 IP Networking
ONS 15454 IP Addressing Scenarios
the need to manually enter static routes for ONS 15454 subnetworks. Figure4-7 shows the same network
enabled for OSPF. Figure 4-9 shows the same network without OSPF. Static routes must be manually
added to the router in order for CTC computers on LAN A to comm unicate with ONS 15454 #2 and #3
because these nodes reside on different subnets.
OSPF divides networks into smaller regions, called areas. An area is a collection of networked end
systems, routers, and transmission facilities organized by traffic patterns. Each OSPF area has a unique
ID number, known as the area ID, that can range from 0 to 4,294,967,295. Every OSPF network has one
backbone area called “area 0.” All other OSPF areas must connect to area 0.
When you enable ONS 15454 OSPF topology for advertising to an OSPF network, you must assign an
OSPF area ID to the ONS 15454 network. Coordinate the area ID number assignment with your LAN
administrator. In general, all DCC-connected ONS 15454s are assigned the same OSPF area ID.
Figure 4-8 Scenario 7: OSPF enabled
CTC Workstation
IP Address 192.168.1.100
Subnet Mask 255.255.255.0
Default Gateway = 192.168.1.1
Host Routes = N/A
Router
IP Address of interface “A” to LAN A 192.168.1.1
IP Address of interface “B” to LAN B 192.168.2.1
Subnet Mask 255.255.255.0
ONS 15454 #2
IP Address 192.168.3.20
Subnet Mask 255.255.255.0
Default Router = N/A
Static Routes = N/A
ONS 15454 #1
IP Address 192.168.2.10
Subnet Mask 255.255.255.0
Default Router = 192.168.2.1
Static Routes = N/A
ONS 15454 #3
IP Address 192.168.4.30
Subnet Mask 255.255.255.0
Default Router = N/A
Static Routes = N/A
LAN B
LAN A
Int "A"
Int "B"
SONET RING
55250