[VRRP] recomputing skew time when receiving an advertisement from the master in rfc 5798

Vladica Stanisic <vladica.stanisic@ericsson.com> Mon, 17 January 2011 17:01 UTC

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From: Vladica Stanisic <vladica.stanisic@ericsson.com>
To: "vrrp@ietf.org" <vrrp@ietf.org>, Shukri Abdallah <shukri.abdallah@ericsson.com>
Date: Mon, 17 Jan 2011 12:03:37 -0500
Thread-Topic: recomputing skew time when receiving an advertisement from the master in rfc 5798
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Subject: [VRRP] recomputing skew time when receiving an advertisement from the master in rfc 5798
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Based on the state machine in rfc 5798 on page 23 steps 450-460 when vrrp is in backup state and receives an advertisement there is no step to recompute the skew time. While in steps 740-765 on page 25 when vrrp is a master and receives an advertisement from some new master, it does recompute the skew time in step 750.
Since skew time is part of master down interval, shouldn't it be recomputed in both states when advertisement is received from a master? Otherwise backup vrrp would continue to use skew time  that was computed based on its configured value for advertisement interval when initially router transitions to backup.
Is this skew time recalculation implied in the backup state or there should be an explicit step like in the master case?

Vladica Stanisic