Echo Function and Asymmetry - Timer negotiation

"Tanya Shastri \(tanyas\)" <> Thu, 11 August 2005 20:58 UTC

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Date: Thu, 11 Aug 2005 13:58:27 -0700
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Thread-Topic: Echo Function and Asymmetry - Timer negotiation
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From: "Tanya Shastri (tanyas)" <>
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Subject: Echo Function and Asymmetry - Timer negotiation
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For an Asynchronous BFD session that has Asymmetric Echo function the
following statements in the spec seem to be misleading, unless I am
missing something.
Section 6.4 says: "When a system is using the Echo function, it is
advantageous to choose a sedate transmission rate for Control packets
since liveness detection is being handled by the Echo packets."
Shouldn't it be the receive rate - or the transmission rate of Control
packets of the remote system - that should be sedate? Also the end that
does not have echo mode active relies on Control packets for liveness
detection and may still want to receive Control packets at a faster
Section 6.7.3 says: " When the Echo function is active, a system SHOULD
set bfd.DesiredMinTxInterval to a value of not less than one second"
>From the description in 6.7.4 this will force the remote end to have a
Detect Timer no faster than 1 second, since the Detect Timer is based on
the transmit rate of the remote system. Also this will not reduce the
rate at which it sends control packets to the end that has echo mode
Wouldn't it be better to suggest that "RequiredMinRxInterval" in BFD
control packets should be set to a minimum of 1 second by the end that
has echo function active?