Integrated Services Digital Network (ISDN) User Part (ISUP) to Session Initiation Protocol (SIP) Mapping
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Auteur(s) : L. Ong
, J. Peterson
, G. Camarillo
, A. B. Roach
Classé sous : Pstn
, Signaling system no. 7
, Public switched telephone network
RFC 3398 ISUP to SIP Mapping December 2002
gateway implements some way of prevent clipping of the initial media
associated with the call.
Unlike a traditional PSTN phone, a SIP user agent can launch multiple
simultaneous requests in order to reach a particular resource. It
would be trivial for a SIP user agent to launch 100 SIP requests at a
100 port gateway, thereby tying up all of its ports. A malicious
user could choose to launch requests to telephone numbers that are
known never to answer, which would saturate these resources
indefinitely and potentially without incurring any charges. Gateways
therefore MAY support policies that restrict the number of
simultaneous requests originating from the same authenticated source,
or similar mechanisms to address this possible denial-of-service
16. IANA Considerations
This document introduces no new considerations for IANA.
This document existed as an Internet-Draft for four years, and it
received innumerable contributions from members of the various
Transport Area IETF working groups that it called home (which
included the MMUSIC, SIP and SIPPING WGs). In particular, the
authors would like to thank Olli Hynonen, Tomas Mecklin, Bill
Kavadas, Jonathan Rosenberg, Henning Schulzrinne, Takuya Sawada,
Miguel A. Garcia, Igor Slepchin, Douglas C. Sicker, Sam Hoffpauir,
Jean-Francois Mule, Christer Holmberg, Doug Hurtig, Tahir Gun, Jan
Van Geel, Romel Khan, Mike Hammer, Mike Pierce, Roland Jesske, Moter
Du, John Elwell, Steve Bellovin, Mark Watson, Denis Alexeitsev, Lars
Tovander, Al Varney and William T. Marshall for their help and
feedback on this document. The authors would also like to thank
ITU-T SG11 for their advice on ISUP procedures.
18. Normative References
 Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A.,
Peterson, J., Sparks, R., Handley, M. and E. Schooler, "SIP:
Session Initiation Protocol", RFC 3261, June 2002.
 Bradner, S., "Key words for use in RFCs to indicate requirement
levels", BCP 14, RFC 2119, March 1997.
 Zimmerer, E., Peterson, J., Vemuri, A., Ong, L., Audet, F.,
Watson, M. and M. Zonoun, "MIME media types for ISUP and QSIG
objects", RFC 3204, December 2001.
Camarillo, et. al. Standards Track [Page 64]