Authentication Types; Rip Screen - ZyXEL Communications Unified Security Gateway ZyWALL 300 User Manual

Chapter 13 Routing Protocols
RIP uses UDP port 520.

13.1.2 Authentication Types

Authentication is used to guarantee the integrity, but not the confidentiality, of routing
updates. The transmitting router uses its key to encrypt the original message into a smaller
message, and the smaller message is transmitted with the original message. The receiving
router uses its key to encrypt the received message and then verifies that it matches the smaller
message sent with it. If the received message is verified, then the receiving router accepts the
updated routing information. The transmitting and receiving routers must have the same key.
The ZyWALL supports three authentication methods for RIP and OSPF routing protocols:
• None - no authentication is used.
• Text – authentication using a plain text password, and the (unencrypted) password is sent
over the network. This method is usually used temporarily to prevent network problems.
• MD5 – authentication using an MD5 password and authentication ID.
MD5 is an authentication method that produces a 128-bit checksum, called a message-digest,
for each packet. It also includes an authentication ID, which can be set to any value between 1
and 255. The ZyWALL only accepts packets if these conditions are satisfied.
• The packet's authentication ID is the same as the authentication ID of the interface that
received it.
• The packet's message-digest is the same as the one the ZyWALL calculates using the
MD5 password.
For RIP, authentication is not available in RIP version 1. In RIP version 2, you can only select
one authentication type for all interfaces. For OSPF, the ZyWALL supports a default
authentication type by area. If you want to use this default in an interface or virtual link, you
set the associated Authentication Type field to Same as Area. As a result, you only have to
update the authentication information for the area to update the authentication type used by
these interfaces and virtual links. Alternatively, you can override the default in any interface or
virtual link by selecting a specific authentication method. Please see the respective interface
sections for more information.

13.2 RIP Screen

The RIP screen is used to specify the authentication method, and it is used to maintain the
policies for redistribution.
To access this screen, login to the web configurator. When the main screen appears, click
Network > Routing > RIP to open the following screen.
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