Specifying Md5 Start And Stop Timing; Figure 19: Packet Flow Between Routers With And Without Authentication - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - IP-IPV6-IGP CONFIGURATION GUIDE 2010-10-31 Configuration Manual

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Figure 19: Packet Flow Between Routers With and Without Authentication

Set

Specifying MD5 Start and Stop Timing

With each of the MD5 commands, you can specify when the router will start and stop
accepting packets that include a digest made with this key. You can also specify when
the router will start and stop generating packets that include a digest made with this key.
If you specify a time for any of these actions, you can further specify the day, month, and
year. The default times are as follows:
Start accepting keys (startAcceptTime)—Current time
Stop accepting keys (stopAcceptTime)—Never
Start generating keys (startGenTime)—Current time plus 2 minutes
Stop generating keys (stopGenTime)—Never
If you specify times, you must follow these guidelines to achieve appropriate timing
between the actions:
startAcceptTime must be less than startGenTime.
stopGenTime must be less than stopAcceptTime.
When a new key replaces an old one, the startGenTime time for the new key must be
less than or equal to the stopGenTime time of the old key.
For example, suppose you configure authentication on router A and router B. If the
startGenTime for router A is earlier than the startAcceptTime for router B, router B does
not accept packets from router A until the current time matches its startAcceptTime.
The router accepts any packet authenticated with a key you have defined if the packet
is received within the period defined for the key by its startAcceptTime and
stopAcceptTime. If more than one key has been defined for that period, the router
determines which key to use by comparing the startGenTime with the current time. When
the startGenTime of a key matches the current time, the router starts using this key to
transmit packets and stops using the previous key.
Example
The following commands configure both key 1 and key 2 to be accepted between
08:00:00 and 23:00:00. When the current time reaches 09:00:00, the router begins
Chapter 6: Configuring IS-IS
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