The MPLS WG Archive[Date Prev][Date Next][Thread Prev][Thread Next] [Date Index][Thread Index][Author Index][Subject Index] PHP negotiation
From: James Huang@MITEL on 01/24/2001 02:06 PM PST
I found in sec 6 of RFC 3036 that PHP negotiation is an area of future study for
LDP. Is it also an area of future study for RSVP-TE? Before this negotiation
mechanism becomes available, I presume we can only reply on manual
configuration on a per peer basis.
-- James Huang
Bora Akyol <akyol@pluris.com> on 01/24/2001 12:33:03 PM
To: James Huang/USA/Mitel@Mitel
cc: Bora Akyol <akyol@pluris.com>, mpls@UU.NET
Subject: Re: PHP negotiation
There is no such mechanism. The assumption is that the network
operator knows how to configure their equipment and they know
their network.
Bora
>>>>> "James" == James Huang <James_Huang@Mitel.COM> writes:
James> From: James Huang@MITEL on 01/24/2001 12:03 PM PST Hi
James> Bora: Maybe I did not express my concern clear
James> enough. As you said, the LSP setup will fail when
James> the egress LSR assigns an Implicit NULL label to the
James> penultimate hop, if the penultinate hop does not
James> support PHP. So there should be some negotiation
James> mechanism in LDP or RSVP/TE such that an egress
James> router will know not to assign an Implicit NULL label
James> to a penultimate hop that does not support PHP. But
James> I can not find such mechanism in the documents.
James> -- James Huang
James> Bora Akyol <akyol@pluris.com> on 01/23/2001 08:24:45
James> PM
James> To: James Huang/USA/Mitel@Mitel cc: mpls@UU.NET
James> Subject: PHP negotiation
James> You should also read the label encapsulation
James> RFC. What happens is that the egress LSR assigns an
James> (...) NULL label (I think it should be Implicit Null)
James> to the penultimate hop, if penultimate hop does not
James> support this, then LSP setup should fail.
James> There was a LOOONG discussion on this sometime last
James> year.
James> Some people think this stuff is really clear. I think
James> that it is in about three different RFCs, and someone
James> needs to write a BCP that explains common usage and
James> tricks that network operators that use MPLS should
James> use.
James> BTW, this question comes up about once a month on the
James> list, maybe we should have an MPLS FAQ.
James> Bora
>>>>> "James" == James Huang <James_Huang@Mitel.COM> writes:
James> Hi all, The following paragraph is from Section
James> 3.16. (Penultimate Hop Popping) of RFC3031.
James> "Initial label distribution protocol negotiations
James> MUST allow each LSR to determine whether its
James> neighboring LSRS are capable of popping the label
James> stack. A LSR MUST NOT request a label distribution
James> peer to pop the label stack unless it is capable of
James> doing so."
James> However, I can not find any mechanism in LDP/CR-LDP
James> or RSVP-TE to accomplish this PHP negotiation.
James> Am I missing something here?
James> -- James Huang
|
|