Hmac Md5 Authentication; Md5 Authentication Example - Juniper IGP - CONFIGURATION GUIDE V11.1.X Configuration Manual

JUNOSe 11.0.x IP, IPv6, and IGP Configuration Guide
NOTE: The router supports simple authentication for compatibility with existing IS-IS
implementations. However, we recommend that you do not use the simple
authentication method because it is insecure (the text can be "sniffed" ).

HMAC MD5 Authentication

When you enable IS-IS HMAC MD5 authentication (also referred to as MD5
authentication), the router creates secure digests of the packets, encrypted according
to the HMAC MD5 message-digest algorithms. The digests are inserted into the packets
from which they are created. Depending on the commands you issue, the digests
can be inserted into hello packets, link-state PDUs, complete sequence number PDUs,
and partial sequence number PDUs.
You can configure an HMAC MD5 authentication key by using the following
commands:
These commands enable MD5 authentication of LSPs and (for the isis
message-digest-key command) hello packets only; they do not enable authentication
of CSNP and PSNP packets. To enable authentication of CSNPs or PSNPs, you must
issue either the area-authentication command or the domain-authentication
command. For information, see "Enabling and Disabling Authentication of CSNPs
and PSNPs" on page 332.

MD5 Authentication Example

In the example shown in Figure 19 on page 331, authentication is configured on router
LA and router SanDiego, but not on router SanJose. Router LA and router SanDiego
accept packets from each other because they contain message digests generated by
an accepted key. Router SanJose accepts packets from router LA and router SanDiego,
and simply ignores the message digest included in their packets. Router LA and
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Overview
The area-message-digest-key command specifies an HMAC MD5 key that the
router uses to create a message digest of each level 1 packet LSPs, CSNPs, and
PSNPs transmitted by area routers. Using MD5 authentication for area routers
protects against unauthorized routers injecting false routing information into the
area portions of your network. This command also enables MD5 authentication
of level 1 LSPs.
The domain-message-digest-key command specifies an HMAC MD5 key that the
router uses to create a message digest of each level 2 packet LSPs, CSNPs, and
PSNPs transmitted by domain routers. Using MD5 authentication for domain
routers protects against unauthorized routers injecting false routing information
into the routing domain portions of your network. This command also enables
MD5 authentication of level 2 LSPs.
The isis message-digest-key command specifies an HMAC MD5 key that the
router uses to create a message digest of level 1 or level 2 hello packets on the
interface. Level 1 packets are the default. Using MD5 authentication on interfaces
protects against intrusion by preventing unauthorized routers from forming
adjacencies with your router. This command also enables MD5 authentication
of level 1 or level 2 hello packets.