RFC 3263 SIP: SIP 포지셔닝 서버

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    .                | Proxy |------------- | Proxy |                  .

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    .   |       |              .          .                |       |   .

    .   |       |              .          .                |       |   .

    .   | UA 1  |              .          .                | UA 2  |   .

    .   |       |              .          .                |       |   .

    .   +-------+              .          .                +-------+   .

    .              Domain A    .          .   Domain B                 .

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                        Figure 1: The SIP trapezoid

Table of Contents



   1          Introduction ........................................    2

   2          Problems DNS is Needed to Solve .....................    2

   3          Terminology .........................................    5

   4          Client Usage ........................................    5

   4.1        Selecting a Transport Protocol ......................    6

   4.2        Determining Port and IP Address .....................    8

   4.3        Details of RFC 2782
 Process .........................    9

   4.4        Consideration for Stateless Proxies .................   10

   5          Server Usage ........................................   11

   6          Constructing SIP URIs ...............................   12

   7          Security Considerations .............................   12

   8          The Transport Determination Application .............   13

   9          IANA Considerations .................................   14

   10         Acknowledgements ....................................   14

   11         Normative References ................................   15

   12         Informative References ..............................   15


Rosenberg & Schulzrinne     Standards Track                     [Page 1]


RFC 3263               SIP: Locating SIP Servers               June 2002




   13         Authors' Addresses ..................................   16

   14         Full Copyright Statement ............................   17