SIP in higher education

[Garret Yoshimi <>]

Hi folks,

Apologies for the delay in these notes from our last call (and the 
abbreviated list of attendees since I was slow in starting the 
recording); I'm catching up on my e-mail piles after being on the road 
for a couple of weeks.

We have a couple of topics in the queue for the summer; please feel free 
to suggest speakers or topics for future calls.

Best.
garret

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Notes for VoIP SIG+SIP.edu Conference Call - May 17, 2007

*Attendees*

Chris Casswell, MCNC
Todd Edwards, Wake Forest
Dave Laurentino, Research In Motion
Deke Kassabian, University of Pennsylvania
Candace Holman, Independent
Phil Kulick, Penn State
Jonathan Tyman, Internet2
Chris Trown, University of Oregon
Garret Yoshimi, University of Hawaii
... and several others ;-)

*Discussion*

Today's call features Bill Rich, the president and CEO of Pingtel, 
providing a overview of open source SIP software. Bill starts by talking 
about a recent survey that he completed for ACUTA on VoIP deployment, 
which included a question about open source. The results indicate that 
while a large number of respondents are considering open source 
applications, 54% are not. A similar survey from three years ago 
indicates that there are greater numbers of people interested in open 
source now. Bill feels that this is representative of the early state of 
VoIP deployment, where people are starting to experiment but have yet to 
fully investigate open source options.
Bill talks about the Internet 2 reference architecture for VoIP, which 
he feels is a strong intersection between open source communications and 
VoIP. The reference drives what he calls the decomposed model, which 
allows organizations to build their own solutions using best-of-breed 
components in a vendor-neutral manner. This enables groups to deploy 
services at their own pace and encourages innovation at every level of 
the chain. Call control, networking, applications, and devices can all 
be configured and combined in ways that were previously impossible and 
in a manner that is diametrically opposed to the traditional TDM 
hierarchy, which focused on tightly integrated single-vendor solutions. 
This traditional approach, in Bill's opinion, offered limited 
flexibility and innovation as well as elevated costs. The arrival of 
open source communications systems has led to systems based on standard 
protocols with more choices for handsets and applications, as well as 
lower costs and quicker development cycles. Bill notes that some 
traditional vendors are developing VoIP solutions, but they are still 
based on the single-vendor models and often use proprietary or modified 
protocols, closed software, and limited choices for hardware.

One key element of open source is that the software is freely available. 
Customers can set up and configure the software on their own at no cost, 
or purchase supported versions for lower cost than traditional software. 
The open nature of the software leads to faster development and more 
innovation. Bill notes that there are several myths regarding open 
source, which he debunks. The open nature of the software leading to 
security risks is one such myth; the idea is that since anyone can 
contribute to the code it is easy to add malicious code. In reality this 
is unlikely, as projects are centrally managed and contributions are 
examined thoroughly before being integrated.

Another myth is that the software is of lower quality since it is free 
and nobody makes money from developing it. In reality, most large open 
source applications are funded by companies who pay developers and 
perform QA work on the resulting software, often indemnifying customers 
to ensure trust.

A third myth is that using open source software ends up being more 
expensive due to development and support costs. Bill notes that most 
major open source applications are available as commercial packages with 
support, and users are only on their own if they choose to be. 
Management tools for open source software have also gotten quite good, 
with most offering GUI applications rather than the traditional 
command-line interfaces.

Bill discusses the two major open source SIP projects: SIPfoundry and 
Asterisk. SIPfoundry is an IP PBX application sold as a commercial 
product by Pingtel and meant to serve as a unified SIP-based 
communication core, using SIP terminals and extensions. The SIPxchange 
software is sold by Pingtel on a subscription model, where customers pay 
a certain amount per server per year, up to a particular number of 
users. At the end of the subscription, the organization can continue to 
use the software at no cost, but would lose support. Pingtel performs a 
variety of testing and integration work with third party phones and 
gateways, and employs most of the SIPfoundry developers. The product is 
available as software only or as a complete package with all necessary 
hardware, handsets, and servers.

The other major open source SIP product is Asterisk, which has been 
around for close to seven years and is widely known and used. Asterisk 
is popular with a number of small businesses, though there are plenty of 
larger deployments as well, and is often used as a stand-alone voicemail 
application. It is mainly commercialized by Digium, whose business model 
focuses on selling cards to work with Asterisk. Other open-source 
packages mentioned by Bill include SER, which is a SIP router, and 
FreeSWITCH which is an outgrowth of Asterisk.

Bill offers a real-world example of costs for Pingtel's SIPxchange ECS 
product. For 25 users, with hardware, a media gateway, the SIP server, 
Polycom 430 phones, and a software subscription, including installation 
and support, the cost would be $300 per seat. Moving up to 200 users 
brings the cost down to $258 per seat, which is very cost effective 
compared to traditional solutions. Bill also notes that the major cost 
is for the IP phones, with the Polycom offered as a very 
middle-of-the-road solution. The real question, he says, is if the 
open-source SIP solution is ready for deployment in mission-critical 
applications. Bill feels that this answer is a definitive yes.

All of Pingtel's software goes through traditional software development 
practices, with releases in phases, QA, and faster release cycles of 
three to four months. The majority of common features from other 
communications software are available, as is support, a suite of 
management tools, and the ability to integrate with technologies like 
SOAP and LDAP. Current customers include a variety of colleges with 
deployments from 500 to 2000 users, with plans to scale to 3000 total. 
Amazon is also a customer, running their Seattle offices on Pingtel 
systems. Bill says that there is probably a limit of about 10,000 users 
on one server, but at a cost of $5,000 to $7,000 per server it is not 
difficult to add more servers while remaining less expensive than 
traditional systems.

Susan from Boston University asks about security measures in SIPxchange. 
Bill says that both products incorporate TLS, and secure SIP signaling 
and media available by the end of 2007.

Deke from Penn asks about the ability to do bridged line appearance and 
busy indicator across multiple lines. Bill says that BLA is available in 
SIPfoundry 4.0, which is scheduled for the end of summer and will work 
across differently phone types. Certain phones will things slightly 
differently, and initial support will probably be for Polycom and SNOM 
phones.

Garret asks about installations for over 10,000 users. He's seen a lot 
of deployments in the 100's and low 1,000's, but asks if anyone is 
seriously looking at 30,000 to 40,000 line implementations. Bill 
believes that this is the case, but would like to qualify his statement. 
There are currently live implementations of greater than 5,000 lines, 
and he's confident that 10,000 would work on high-availabiltiy 
load-balanced servers. There is also work done on isolating specific 
aspects, such as media or call center loads, onto different servers. In 
lab tests these systems can handle 20 to 25 calls per second, so two or 
three systems would work for 30,000 people. Voicemail and dialing plans 
are another concern, but it's possible to have multiple systems using 
one voicemail system.

Finally, Bill is asked about E911 support and lawful intercept. He says 
that E911 is supported, but lawful intercept currently is not as in the 
past it has been thought of as happening once traffic has moved to a 
public network. He understands why this would be desirable, though, and 
says that it is being worked on.

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