RFC 5880, "Bidirectional Forwarding Detection (BFD)", June 2010

Note: This RFC has been updated by RFC 7419, RFC 7880, RFC 8562, RFC 9747

Errata ID: 4410
Status: Held for Document Update
Type: Editorial
Publication Format(s) : TEXT
Reported By: Liu Lin
Date Reported: 2015-07-07
Held for Document Update by: Alvaro Retana
Date Held: 2016-02-16

Section 6.8.4 says:

If Demand mode is active, and a period of time equal to the Detection
Time passes after the initiation of a Poll Sequence (the transmission
of the first BFD Control packet with the Poll bit set), the session
has gone down

It should say:

If Demand mode is active, and a period of time equal to the Detection
Time passes after the initiation of a Poll Sequence (the transmission
of the first BFD Control packet with the Poll bit set),and without 
receiving a BFD Control packet with the Final (F) bit set from the
remote system, the session has gone down

Notes:

If has received BFD Control packet with the Final (F) bit set from the
remote system, the session will not gone down

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