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<DIV><FONT size=2>Hello all!</FONT></DIV>
<DIV><FONT size=2>I would like to bring your attention to the topic in the
attached e-mail.</FONT></DIV>
<DIV><FONT size=2>The intend of the proposed procedure is to use DHC Protocol at
the bootstrap time in order to receive the IP address(es) of SIP (Proxy)
Server(s). In other words, a kind of RAS Discovery procedure for
SIP.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2>The purpose to this e-mail is not to compare between the two
procedures. My thinking is that end devices should support more then one
procedure for the same purpose (especially when it is a configuration
issue). In this way they are flexible and can be deployed in
various environments.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2>My concern is that the functionality described in this
proposal (see the attachment) is by no means SIP-specific. There are many
application level protocols that require this sort of functionality, i.e.
they relay on application-specific Server (or a list of possible Servers),
whose IP address(es) should be discovered. The examples only in our area are
H.323 and MEGACO. Taking a look into "Procedure for Defining New DHCP Options"
RFC-2489 you will find that "the option number space for publicly defined DHCP
options has almost been exhausted" and this is the whole reason for the new
procedure defined by RFC-2489. More then that: in order to solve this allocation
problem "groups of related options may be combined into a single specification
and reviewed as a set by the IESG".</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2>Based on this I would like to request from SIP Working group
to review their proposal (possibly as a part of "fast track" procedure).
Opinions?</FONT></DIV>
<DIV><FONT size=2>Orit Levin<BR>RADVision Inc.<BR>575 Corporate Drive Suite
420<BR>Mahwah, NJ 07430<BR>Tel: 1 201 529 4300 (230)<BR>Fax: 1 201 529
3516<BR><A href="http://www.radvision.com">www.radvision.com</A><BR><A
href="mailto:orit@radvision.com">orit@radvision.com</A></FONT></DIV></BODY></HTML>