RE: [Sip] draft-jennings-sip-dtls

["Tolga Asveren" <[e-mail]>]

MessageIsn't "running out of sockets" an implementation issue rather than a
protocol one?

And I believe using multiple processes would solve that problem.

  Tolga
  -----Original Message-----
  From: [e-mail] [mailto:[e-mail]]On Behalf Of
Christian Stredicke
  Sent: Wednesday, February 16, 2005 5:02 PM
  To: Francois Audet; Cullen Jennings; Jonathan Rosenberg
  Cc: [e-mail]
  Subject: RE: [Sip] draft-jennings-sip-dtls


  Today I would recommend SIP operators to avoid TCP (and that includes TLS)
because the processes are simply running out of sockets (think about an ITSP
with one million customers). The UDP/DTLS idea would make it reasonable
simple to have much more connections and on top have security. And as far as
I understood the dtls it finally does solve the fragmentation pain problem.

  That sounds like a great thing to me. I would vote for dtls!

  CS



----------------------------------------------------------------------------
    From: [e-mail] [mailto:[e-mail]] On Behalf Of
Francois Audet
    Sent: Wednesday, February 16, 2005 9:47 PM
    To: 'Cullen Jennings'; 'Jonathan Rosenberg'
    Cc: [e-mail]
    Subject: RE: [Sip] draft-jennings-sip-dtls


    I would agree with Jonathan.

    Yes, some implementations of SIP/TCP have performance issues compared to
SIP/UDP, but not necessarily all of them.

    Also, if we need to address the other problems of UDP transport (like
fragmentation, and others), then it is not clear to me that we are saving
much in the first place by using UDP/DTLS instead of TCP/TLS.

    I'd like to see real data before we add yet another thing we'll have to
implement...
      -----Original Message-----
      From: [e-mail] [mailto:[e-mail]] On Behalf Of
Cullen Jennings
      Sent: Tuesday, February 15, 2005 20:08
      To: Jonathan Rosenberg
      Cc: [e-mail]
      Subject: Re: [Sip] draft-jennings-sip-dtls



      Oops - I meant to put that.... There is pretty much one key thing. No
one has build an single edge proxy that can terminate 100k to 1M connections
to UAs using TLS. In theory it is possible, but in practice it seems hard.
The argument is that this will be easier with DTLS. The issue is not the
time it takes to do the crypto - session resumption deals with that nicely -
it just the issues of dealing with half a million TCP connections to one
box. Of course no one has done it with DTLS either :-)

      I believe the argument we made for SCTP was that adding an extensions
for SCTP won't increase the complexity of things that don't support SCTP.

      I agree the UDP/TCP complexity made SIP more complicated and I agree
that sip and sips made things more complicated. I'm not sure I buy that both
TLS and TCP made things more complicated.


      On 2/15/05 7:15 PM, "Jonathan Rosenberg" <[e-mail]> wrote:


        Cullen,

        What seems missing to me from this is requirements and problem
        statements. What is DTLS doing for us that we don't get from TLS?

        Though SIP can run over many different transport protocols, I think
        experience over time has shown that more choices here is not
necessarily
        a good thing, as SIP has a fair bit of complexity as a result of
dealing
        with the differences between UDP and TCP. As such, I don't think its
a
        good idea to just add more transport protocols to SIP's list of
        supported ones unless there is a compelling problem that it is
solving.

        Thanks,
        Jonathan R.

        Cullen Jennings wrote:

        >
        > Nagendra and I put together a draft on using DTLS with SIP. Until
it
        > shows up in the archives you can find it at
        >
        >
http://scm.sipfoundry.org/rep/ietf-drafts/fluffy/draft-jennings-sip-dtls-00.
html
        >
        > (there is a .txt version too)
        >
        >
        > The abstract is:
        >
        >    This draft specifies how to use Datagram Transport Layer
Security
        >    (DTLS) as a transport for SIP.  DTLS is a new protocol for
providing
        >    TLS security over a datagram protocol.
        >
        >






  > ------------------------------------------------------------------------
        >
        > _______________________________________________
        > Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
        > This list is for NEW development of the core SIP Protocol
        > Use [e-mail] for questions on current sip
        > Use [e-mail] for new developments on the application of
sip

_______________________________________________
Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
This list is for NEW development of the core SIP Protocol
Use [e-mail] for questions on current sip
Use [e-mail] for new developments on the application of sip