Specifications

Distribution Layer April 2014
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Step 4: Configure IP address summarization on the links to the core.
As networks grow, the number of IP subnets or routes in the routing tables grows as well. You configure IP
summarization on links where logical boundaries exist in order to reduce the amount of bandwidth, processor
speed, and memory necessary to carry large route tables and to reduce convergence time around a link failure.
If the connected device provides connectivity to another piece of the network (for example, the WAN, Internet, or
LAN core), configure summarization.
EIGRP Summarization
router eigrp CAMPUS
address-family ipv4 unicast autonomous-system 100
af-interface [interface type] [number]
summary-address 10.4.0.0 255.255.240.0
exit-af-interface
exit-address-family
OSPF Summarization
router ospf 100
area [unique area number] range 10.4.0.0 255.255.240.0
Step 5: Configure router neighbor authentication, and override passive interface configuration for links to the
core.
After you have configured the Layer 3 interfaces and Layer 3 port-channels connecting to other Layer 3 devices,
allow the routing protocol to form neighbor relationships with MD5 authentication across these interfaces to
establish peering adjacencies and exchange route tables.
Unlike EIGRP named mode configuration, OSPF neighbor authentication also requires a configuration attached
directly to the Layer-3 interfaces, thus additional router neighbor authentication configuration is completed as
part of the prior Layer-3 interface configuration steps.
EIGRP Neighbor Authentication
key chain CAMPUS-KEY
key 1
key-string [key]
!
router eigrp CAMPUS
address-family ipv4 unicast autonomous-system 100
af-interface [interface type] [number]
authentication mode md5
authentication key-chain CAMPUS-KEY
no passive-interface
exit-af-interface
exit-address-family
OSPF Neighbor Authentication
router ospf 100
area 0 authentication message-digest
no passive-interface [interface type] [number]