MD5 Authentication for RIPV2

Wow I think today has been by far the most active on my blog, trying to make up for lost time I guess :)

Anyway RIP authentication is perhaps the easiest of all to get going, however during setting up the lab it gave me the most trouble.

Cisco lists 3 requirements for getting RIP authentication working they are:

* Key-string
* Key number
* Authentication mode

However I would like to add a fourth (at least for my IOS) and that is that the key chain needed to be defined before being included in the "ip rip authentication key-chain RIP_KEY"

So there is the config R1:
1) Key Chain

key chain RIP_KEY
key 1
key-string ripme


2) RIP Authentication on the Interface:

ip rip authentication mode md5
ip rip authentication key-chain RIP_KEY


R5
1) Key Chain

key chain RIP_KEY
key 1
key-string ripme


2) RIP Authentication on the Interface:


ip rip authentication mode md5
ip rip authentication key-chain RIP_KEY


MD5 Authentication for OSPF Virtual Links

Virtual Links are links through transit areas back to Area 0
Therefore once MD5 authentication has been configured on Area 0 the virtual links require setting up for MD5.

NB:Done under the "router ospf" instance

R1

router ospf 1
router-id 1.1.1.1
log-adjacency-changes
area 12 virtual-link 2.2.2.2 authentication
area 12 virtual-link 2.2.2.2 message-digest-key 1 md5 letme0


R2

area 12 virtual-link 1.1.1.1 authentication
area 12 virtual-link 1.1.1.1 message-digest-key 1 md5 letme0
area 23 virtual-link 3.3.3.3 authentication
area 23 virtual-link 3.3.3.3 message-digest-key 1 md5 letme0



R3

area 23 virtual-link 2.2.2.2 authentication
area 23 virtual-link 2.2.2.2 message-digest-key 1 md5 letme0


MD5 Authentication for OSPF Areas

MD5 Authentication for OSPF areas is done on the interface.

Here are a couple of examples:


Area 34 - Between R3 and R4

R3

interface Serial1
ip address 192.168.34.3 255.255.255.0
encapsulation ppp
ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 letme34


Then to match that on R4

interface Serial0
ip address 192.168.34.4 255.255.255.0
encapsulation ppp
ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 letme34
clock rate 4000000
no fair-queue


For ISDN it is done on the Dialer:

R1

ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 letme12
! Suppress the "hello"s to stop the line coming up
ip ospf demand-circuit


R2

ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 letme12
! Suppress the "hello"s to stop the line coming up
ip ospf demand-circuit


Area 0 (Frame Relay)
R1

interface Virtual-Template1
ip unnumbered Serial0/0.123
ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 letme0


R3

interface Virtual-Template1
ip unnumbered Serial0/0.321
ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 letme0