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Re: [] Call Notes - 11/3

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  • From: (Dennis Baron)
  • To:
  • Subject: Re: [] Call Notes - 11/3
  • Date: Mon, 14 Nov 2005 14:50:23 -0500 Conference Call November 03, 2005


Dennis Baron, MIT
Jeff Kuure, Internet2
Mark Spencer, Indiana University
John Steir, Stony Brook University
Ben Teitelbaum, Internet2
John Todd, Tello
Mike Van Norman, UCLA
Doug Walston, Cisco
Dave Zimmerman, UC Berkeley


Today's call begins with Dennis discussing recent changes at MIT. They
have fixed the Cisco gateway problem mentioned in the last call, and
most systems are now running on Cisco gateways and SER. After the call,
the DNS records will be moved from Pingtel to SER. MIT has also recently
completed campus-wide wireless coverage, and wireless SIP phones are
starting to show up.

John Todd asks if MIT's wireless network is using any sort of
encryption. Dennis says that everything is open, but access is by DHCP
restricted by MAC address. John mentions that he's encountered some recent
media coverage of SIP that has cited the lack of encryption, and hopes
this won't lead to any sort of backlash against VOIP in general. Dennis
has mixed feelings - he hopes such coverage would lead to more people
investigating technologies like secure RTP; on the other hand, he doesn't
like to see VoguyIP portrayed as evil for lacking encryption.

Following this, John Todd mentions the Soekris Net 4801, which is a
small embedded system containing a Sangoma single- or dual-port T1
card for about $600. This system provides an entry-level integration
between Asterisk and an existing PRI-based telephony system for inbound or
outbound calls. It runs Astlinux, a version of Asterisk, and boots off of
a flash card. It does basic call mapping using the Asterisk toolkit. John
says that this would work well on a small scale, but would not be suitable
for handling a large volume of calls or using high-complexity codecs.

Dennis mentions that he recently received a call from Excel Switching, who
make soft switches as well as PRI and SS7 gateways. They are interested
in finding schools to test their new equipment, consisting of a 1U DS3
gateway. Dennis will contact them about possibly participating in a
future call.

Ben is still working on the ISN cookbook, which is available at Currently, there is a SER recipe,
and he is incorporating John Todd's Asterisk recipe. Comments from
participants are welcome.

Dennis was emailed by Ed Guy, who has completed outgoing ISN access. The
access code is **012 for the time being.

In the last call, the question of caller ID came up. There does not seem
to be an easy solution to the question of how to handle the passing of
caller identity between various networks and dialing plans. The goal is
to not break URI-style calling, if possible. The remainder of
the call centers around discussion of possible solutions - using the
Cisco RPID field to insert the caller identity is what Dennis favors,
but this is not necessarily a widely-supported standard. Another
possibility is rewriting the "from" headers of calls based on their
origin and destination. Allowing multiple "from" headers and letting
the receiving end decide what to display would also be a solution, but
no one is sure if this is allowed by the RFC. Ben believes that proxies
are not allowed to alter the from line, which might limit this approach.

John Todd mentions that Alan Johnston, who wrote a lot of the SIP RFC,
has recently started working at Tello; John will consult with him
regarding this question to see if he has any insight.

Call participants agree that questions about caller identification must
have come up before, and feel that there has to be something that they
are missing. Dennis asks how far people are willing to go in pursuit of
a solution, as such options as proposing new standards, collaboration
with vendors, or requiring campuses to run back-to-back user agents may
be necessary.

The call concludes with John Todd discussing progress towards ISN
dialing. There are several test setups currently running, and some of
the latest ITAD requests are waiting for entry in the namespace. Contact


with DNS questions or for pointers
on getting things working.

The next call will be on Thursday, November 17th.

  • Re: [] Call Notes - 11/3, Dennis Baron, 11/14/2005

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