# isis message-digest-key

#### Syntax

isis message-digest-key keyId hmac-md5 key
[ start-accept startAcceptTime [ { startAcceptMonth startAcceptDay | startAcceptDay startAcceptMonth } startAcceptYear ] ]
[ start-generate startGenTime [ { startGenMonth startGenDay | startGenDay startGenMonth } startGenYear ] ]
[stop-accept { never | stopAcceptTime [ { stopAcceptMonth stopAcceptDay | stopAcceptDay stopAcceptMonth } stopAcceptYear ] } ]
[ stop-generate { never | stopGenTime [ { stopGenMonth stopGenDay | stopGenDay stopGenMonth } stopGenYear ] } ] [ level-1 | level-2 ]

no isis message-digest-key keyId [ level-1 | level-2 ]

#### Release Information

Command introduced before JunosE Release 7.1.0.

#### Description

Specifies an HMAC MD5 key that the router uses to create a secure, encrypted message digest of IS-IS level 1 or level 2 hello packets on the interface. Level 1 packets are the default. The digest is inserted into the packet from which it is created. Using this algorithm protects against intrusion by preventing unauthorized routers from forming adjacencies with your router.

You can specify when the router will start (default is the current time) and stop (default is never) accepting packets that include a digest made with this key. You can specify when the router will start (default is the current time plus 2 minutes) and stop (default is never) generating packets that include a digest made with this key. The no version deletes the key specified by the keyId.

#### Options

- keyId—Integer from 1 to 255 that is a unique identifier for the secret key, sent with the message digest in the packet.
- key—String of up to 20 alphanumeric characters; secret key used by the HMAC MD5 algorithm to generate the message digest.
- startAcceptTime, startAcceptMonth, startAcceptDay, startAcceptYear—Time, month, day, year that the router will start accepting packets created with this password. Use military time format HH : MM[ : SS ].
- startGenTime, startGenMonth, startGenDay, startGenYear—Time, month, day, year that the router will start inserting this password into packets. Use military time format HH : MM[ : SS ].
- never—Specifies that the router never stops accepting or generating packets; overrides previously specified stop times.
- stopAcceptTime, stopAcceptMonth, stopAcceptDay, stopAcceptYear—Time, month, day, year that the router will stop accepting packets created with this password. Use military time format HH : MM[ : SS ].
- stopGenTime, stopGenMonth, stopGenDay, stopGenYear—Time, month, day, year that the router will stop inserting this password into packets. Use military time format HH : MM[ : SS ].
- level-1—Inserts the password into level 1 hello packets
- level-2—Inserts the password into level 2 hello packets

#### Mode

Interface Configuration, Subinterface Configuration