The MPLS WG Archive

Cell Relay Retreat>MPLS WG Archive>month:2000-May> msg00382



[Date Prev][Date Next][Thread Prev][Thread Next]  
  [Date Index][Thread Index][Author Index][Subject Index]

Re: MPLS - ATM interworking?

  • From: CATANZARITI Sergio FTR&D/TI <sergio.catanzariti@rd.francetelecom.com>
  • Date: Wed, 31 May 2000 12:18:59 -0700
  • Cc: mpls@UU.NET, "'Andrzej Czerczak'" <Andrzej_Czerczak/HeadQ@netia.pl>, rraszuk@cisco.com

Title: RE: Re: MPLS - ATM interworking?


    Sorry, in my previous e-mail I meant draft-ietf-mpls-diff-ext-04.txt does not say anything about ECN ...,
    the problem is that I have not received any draft-ietf-mpls-ecn-00.txt.

    Sergio


    --------------------------------------------------------------------
    Sergio Catanzariti
    Senior Project Manager, Technology Integration
    France Telecom R&D
    1000 Marina Boulevard Suite 300
    Brisbane CA 94005
    Tel. 650-875-1526
    Fax. 650-875-1505
    email:sergio.catanzariti@rd.francetelecom.com
    --------------------------------------------------------------------


    -----Original Message-----
    From:   CATANZARITI Sergio FTR&D/TI [SMTP:sergio.catanzariti@rd.francetelecom.com]
    Sent:   Wednesday, May 31, 2000 12:13 PM
    To:     'Shahram Davari'
    Cc:     mpls@UU.NET; 'Andrzej Czerczak'; rraszuk@cisco.com
    Subject:        RE: Re: MPLS - ATM interworking?

    Shahram,

            the draft-ietf-mpls-ecn-00.txt does not say anything about ECN usage and applications, but only about ECN support and definition in an MPLS network, the things are quite different. So, I have the same question: where I can find Ramakrishnan et al., "A Proposal to Incorporate ECN in MPLS", draft-ietf-mpls-ecn-00.txt?

            Also, I do believe that the ECN in an MPLS network works on resource types (LSPs) quite different than native IP flows. So, the source address is not that useful here, albeit in an ECN schema in pure IP networks.

            ECN in an MPLS network is supposed to signal congestion in an edge-to-edge fashion (different from end-to-end) where the LERs could cooperate on that.

            Absolutely, I want to associate LSPs with congestion dynamics to eventually slow them down. How can I do that? That's the question.

    Sergio

            --------------------------------------------------------------------
    Sergio Catanzariti
    Senior Project Manager, Technology Integration
    France Telecom R&D
    1000 Marina Boulevard Suite 300
    Brisbane CA 94005
    Tel. 650-875-1526
    Fax. 650-875-1505
    email:sergio.catanzariti@rd.francetelecom.com
    --------------------------------------------------------------------


            -----Original Message-----
    From:   Shahram Davari [SMTP:Shahram_Davari@pmc-sierra.com]
    Sent:   Wednesday, May 31, 2000 11:34 AM
    To:     'Andrzej Czerczak'; rraszuk@cisco.com
    Cc:     mpls@UU.NET
    Subject:        RE: Re: MPLS - ATM interworking?

            Andrzej,

            1)ECN usage is defined in draft-ietf-mpls-ecn-00.txt, which is attached to
    this email.

            2)Congestion Notification is and end-to-end signal which is meant to be used
    by TCP. You don't need to know the ingress LSR or even the LSP from which
    the congested packet is received. The receiver may send the congestion
    notification to the sender using source IP address, either through another
    LSP or even through normal IP hop-by-hop routing.

            Regards,
    -Shahram




            >-----Original Message-----
    >From: Andrzej Czerczak [ <mailto:Andrzej_Czerczak/HeadQ@netia.pl>]
    >Sent: Wednesday, May 31, 2000 1:46 PM
    >To: rraszuk@cisco.com
    >Cc: mpls@UU.NET
    >Subject: Re:Re: MPLS - ATM interworking?
    >
    >
    >
    >Robert,
    >First of all thanks for your comments.
    >
    >>Have you read draft MPLS Support of Differentiated Services
    >>draft-ietf-mpls-diff-ext-04.txt where we are proposing to use the ECN
    >>(explicit congestion notification) on a per LSP basis using
    >the EXP bits
    >>in the shim header ? Currently this is the most attractive
    >option, but I
    >> am not aware of any implementation support this today.
    >
    >
    >
    >a) Document draft-ietf-mpls-diff-ext-04.txt does not not
    >define the usage
    >of ECN.
    >
    >b) Taking into account label merging capabilites of LSRs, how
    >can determine
    >to which ingress LSP to to send Congestion Notification?
    >
    >c) Where can I find:
    >
    >Ramakrishnan et al., "A Proposal to Incorporate ECN in
    >   MPLS", draft-ietf-mpls-ecn-00.txt?

            >
    >
    >
    >What I'd like to say is, that at least during first phases of
    >implementations (before entire infrastructure will become IP)
    >interworking
    >of MPLS core and ATM edge will be important, but I could not find a
    >proposal of how to do interworking between them.
    >
    >
    >
    >Andrzej
    >
    >
    >
    >
    >
    >
     << File: draft-mpls-ecn-00.txt >>