Hi Carlos,
Thanks for the response. One question in-line (I removed sections that
seem closed.):
Thanks!
Ben.
On 3 May 2016, at 20:12, Carlos Pignataro (cpignata) wrote:
[...]
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DISCUSS:
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Section 4, 2nd paragraph: " If the port is not 7784, then the packet
MUST be looked up to locate
a corresponding SBFDInitiator session or classical BFD session
based
on the value from the "your discriminator" field in the table
describing BFD discriminators. "
Do I understand correctly that whether or not the destination port is
7784 tells you if this is an "initial" packet vs a "reflected"
packet? If
the destination port is not 7784, how do you know it’s not some
competely
different protocol? Do you assume the receiver has no other UDP based
services?
Alia caught the same thing. The text is currently kinda broken as
written in rev -04.
We fixed this as follows based on Alia’s discuss, from our working
copy:
This procedure for an S-BFD packet is executed on both the
initiator
and the reflector. If the port is 7784 (i.e., S-BFD packet for
S-BFDReflector), then the packet MUST be looked up to locate a
corresponding SBFDReflector session based on the value from the
"your
discriminator" field in the table describing S-BFD discriminators.
If the port is not 7784, but the packet is demultiplexed to be for
an
SBFDInitiator, then the packet MUST be looked up to locate a
corresponding SBFDInitiator session based on the value from the
"your
discriminator" field in the table describing BFD discriminators.
In
that case, then the destination IP address of the packet SHOULD be
validated to be for itself. If the packet demultiplexes to a
classical BFD session, then the procedures from [RFC5880] apply.
Which should clarify your point as well.
I think it does, and will clear the discuss. For my own curiosity: do I
understand correctly, that the non 7784 port would be a port that a
reflector learned from the source-port of an initiator message, which by
necessity be listening for S-BFD packets (based on your answer below
about an initiator listening on it's source port?
[...]
