Hi,
For my part (I only worked as an author quite late in the process, but I was
helping to get this through the IESG review that raised issued about TCP
ports) I think Julien has not captured the point.
The RFC is not silent about source ports because it does intend to limit the
scope.
As Julien says, it does matter which port is listened on, and this is
deliberately a well-known port number so that it is not necessary to
configure (or advertise) the port that must be called.
But in Section 4.2.1 you will find...
Only one PCEP session can exist between a pair of PCEP peers at any
one time. Only one TCP connection on the PCEP port can exist between
a pair of PCEP peers at any one time.
One way to help ensure this is to reduce the number of available ports to
use as the source port.
Does restricting the source port cause any implementation or deployment
problems?
Thanks,
Adrian
----- Original Message -----
From: <[email protected]>
To: <[email protected]>; <[email protected]>;
<[email protected]>
Cc: <[email protected]>
Sent: Thursday, September 10, 2009 9:57 AM
Subject: Re: [Pce] PCE port number
Hi Vishwas.
Interesting comment. We must admit the wording is a bit ambiguous.
RFC 5440 says: "The system listens to the PCEP-registered TCP port" and
"Upon receiving a TCP connection on the PCEP-registered TCP port"; I do not
see any behavior description for the source TCP port (good thing!).
My guess is that there is no intend to put constraints on the TCP initiator
port. I would interpret the sentence you mention as "using the registered
TCP port on the PCE side, i.e. for the source TCP port for PCE to PCC
messages and for destination TCP port for PCC to PCE messages"... A little
cumbersome, I agree.
Authors of RFC 5440, would there be an actual intend to specify otherwise?
Implementers, any other interpretation?
Thanks,
Julien
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of
Vishwas Manral
Hi,
I looked at the following in the spec:
“Transport Protocol
PCEP operates over TCP using a registered TCP port (4189). This
allows the requirements of reliable messaging and flow control to be
met without further protocol work. All PCEP messages MUST be sent
using the registered TCP port for the source and destination TCP
port.”
This has been worrying me a bit. Unlike other protocols like BGP or LDP
In BGP it states clearly:
A BGP implementation MUST connect to and listen on TCP port 179 for
incoming connections in addition to trying to connect to peers.
and
BGP's destination port SHOULD be port 179, as defined by IANA.
Why do we have this restriction on source port? It is becoming a
challenging task
in merchant OS.
Thanks,
Vishwas
Vishwas
_______________________________________________
Pce mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/pce
_______________________________________________
Pce mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/pce
_______________________________________________
Pce mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/pce
