Juniper IGP - CONFIGURATION GUIDE V11.1.X, Configuration Manual

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The first 20-byte entry in a RIP authentication message contains an address family
identifier value of 0xffff and a route tag value of 2. If the 0xffff address family is
present in the RIP message, the remaining 16 octets of the entry contain a plain text
password. If the password is fewer than 16 octets, it must be left-justified and padded
to the right with nulls (0x00).
Authentication is applied per RIP interface. You can specify either text or MD5
authentication. Text authentication uses a simple password that must be shared by
the neighbors receiving updates or requests. If they do not have this password, the
neighbors reject all updates or requests from the router. MD5 authentication uses a
shared key to encrypt the RIP message. The neighbors must have the MD5 key to
decrypt the message and encrypt a response.
NOTE: Do not use text authentication when security is important, because the router
sends the unencrypted password in every RIP packet it sends.
Example 1
The following example shows how to use password authentication:
host1(config)# interface fastEthernet 0/0
host1(config-if)# ip rip send version 2
host1(config-if)# ip rip authentication mode text
host1(config-if)# ip rip authentication key ke6G72mV
Example 2
The following example shows how to use MD5 authentication:
host1(config)# interface fastEthernet 0/0
host1(config-if)# ip rip send version 2
host1(config-if)# ip rip authentication mode md5 8
host1(config-if)# ip rip authentication key sf43nBScE9
Subnet Masks
The Subnet Mask field of a RIP message contains the subnet mask that is applied to
the IP address to set the nonhost portion of the address. If the subnet mask field in
a RIP message contains a zero, then no subnet mask was included for the entry.
On an interface where a RIPv1 router may hear and operate on information in a
RIPv2 routing entry, the following rules apply:
■
Information internal to one network must never be advertised into another
network.
■
Information about a more specific subnet may not be advertised where RIPv1
routers would consider it a host route.
■
Supernet routes (routes where a netmask is less specific than the natural network
mask) must not be advertised where they could be misinterpreted by RIPv1
routers.
208 ■
Features
JUNOSe 11.0.x IP, IPv6, and IGP Configuration Guide