While driving up to Vermont with my girlfriend to go skiing,
we had a disagreement on the temperature in the car she was cold and I
was hot, so I was a gentleman and put the heat on. Nicole was still chilled,
so I handed a jacket to her and said, Here, if youre still chilled you
can wear this. Be careful, my phone is in the jacket pocket and it can slip
out. Since she was wearing a dress, she wore it over her legs to stay
warm.
Upon arriving in Vermont, we brought our bags into the house and then
headed out for dinner. We arrived at the restaurant and just as I sat down,
I reached into my jacket and realized my phone was gone. I was a little
concerned since I have never misplaced my phone before, but I figured it
probably slipped out in my car from when Nicole had it over her legs.
After dinner, we drove back and then searched the house, the driveway,
and my car outside in the dark for 25 minutes to no avail. I even tried
calling the phone, but being surrounded by mountains the phone had no signal
and I was sent right into voice mail.
Who Needs A Land-Line Anyway?
Now I was really concerned because this was my only phone. I had cancelled
my land-line and switched to 100 percent mobile phone service for two
reasons. One, I had 3,000 all long distance minutes per month for
$39.99, which was much cheaper than the $200 phone bills I was paying with
my land-line service. Second, I had broadband cable access, so there was no
need for a phone line for dial-up Internet access.
The Mystery Continues
The next morning we searched the 3000GT high and low. Alas, the phone was
nowhere to be found. More annoying than the replacement cost of the phone
was the mystery of where the phone disappeared. Losing the phone was not a
big deal, but I was now temporarily phone-less, disconnected in a
world where staying connected is essential.
Fortunately, the Internet was once again my savior. I already use MSN
Messenger to instant message with coworkers and friends, so I figured that I
could use the voice features embedded within MSN Messenger to stay in touch
with friends and family. MSN Messenger is a SIP-compliant software
application that Ive already tested within TMC Labs making several
PC-to-PC VoIP calls to fellow employees. Certainly, this could be a great
temporary solution until I received my new cell phone in the mail.
Unfortunately, MSN Messenger has issues with NATed firewalls, which means
it doesnt always work. Second, I couldnt expect everyone to turn on
their home computer and wear a headset connected to their PC anytime someone
wanted to talk to me. Third, some friends dont have a home computer at
the moment, so this meant any free PC-to-PC VoIP solution was out of
the picture.
Several days had passed and I still had no phone and thus couldnt call
friends or family. If I had lost my phone 2 years ago, I could have used
DialPads free PC-to-Phone calling plan, but unfortunately like many
Internet companies, theyve switched to a pay model. So I then considered
using MSN Messengers PC-to-Phone feature that allows you to sign up with
an Internet Telephony Service Provider, such as CallServe, DeltaThree, or
Net2Phone. I could then make PC-to-Phone calls via MSN Messenger.
I started this process, but MSN Messenger informed me that my home
firewall was preventing voice communications due to NAT. At the time I just
didnt feel like futzing around with my firewall settings. I decided to
head over to www.net2phone.com and download their CommCenter 1.1
application. After registering my name and credit card information, I
charged it with $10 and made my first very important VoIP call using
CommCenter, a call to a local pizzeria.
Internet Telephony Saves The Day!
The pizza was pretty good and the VoIP voice quality wasnt too bad
either. Using VoIP saved me a trip to order the pizza, not to mention the 20
minutes wait for it to be cooked. Internet telephony truly came to the
rescue! I used some of the $10 balance to call my girlfriend (which, oddly
enough, would have been a free local call if I still had a land-line in my
house, probably one of the few times VoIP is more expensive than PSTN), and
over the course of the next few days, I used Internet telephony to order
pizza and Chinese, and call some friends.
Ironically, while I was attempting to get MSN Messenger to work with a
third-party ITSP, I received an e-mail from Microsoft inviting me to
participate in their beta of their Real Time Communications Server (RTC).
RTC Server is a SIP registrar and proxy that works in conjunction with their
SIP-compliant MSN Messenger client. I should mention that I had been playing
with using MSN Messenger at work in conjunction with Exchange Server to
implement internal corporate instant messaging. Unfortunately, the Exchange
Server instant messaging implementation uses a proprietary protocol, and in
my experience is buggy to say the least. But a SIP implementation, besides
being very open and extensible, is pretty cool, especially with several
interesting SIP applications coming to market (see sidebar
below).
Excited, I immediately downloaded RTC from their Web site along with a
special version of MSN Messenger. I installed RTC on a Windows 2000 Server
and used Microsofts Management Console (MMC) to configure the RTC Server.
Next, I installed the special version of MSN Messenger on a Windows XP PC.
Then I simply selected the Communications Services Account within MSN
Messenger, populated the Sign-in name ([email protected]) and then click
Advanced to the right of the Sign-in name where I then entered the IP
address of the SIP Server (RTC Server) and finally I selected the
appropriate transport (UDP, TCP, or TLS are supported).
I was then able to successfully logon to the SIP-based RTC server. I used
a couple more test PCs to also authenticate on the RTC Server, which would
allow me to make test voice and video calls, as well as send instant
messages. In addition, I tested whether the presence status would
propagate to buddies on the appropriate buddy lists. All of my tests
passed with flying colors even though the RTC Server is still in beta. I
also tested using the Siemens HiPath 100 SIP phone. Unfortunately, I was
unable to get the HiPath 100 to register on the RTC Server. However, the
HiPath 100 SIP phone was able to successfully make a direct SIP call to MSN
Messenger by dialing the IP address.
While Microsoft appears focused on SIP within the enterprise, Hotsip (www.hotsip.com)
appears to be targeting both the enterprise and service providers with their
HotSIP Application Server product. Hotsip was the first company to support
both the SIP and the Wireless Village industry standards, which allows for
direct interoperability with Microsoft, Nokia, Ericsson, and Motorola for
Presence and Instant Messaging services. The Hotsip SIP Application Server
is a platform for developing and deploying complete SIP infrastructure and
application services. Service providers can operate the SIP Application
Server in a wide range of scenarios such as voice, presence, messaging, and
gaming services. The SIP Application Server supports multiple roles,
including proxy, redirect, registrar and application server. In addition it
has an XML interface for configuration as well as SNMP management support.
It supports TCP, UDP, SSL/TLS, and multicast and is interoperable with SIP
clients, including MSN Messenger.
Hey, Whats This On The Floor?
Two weeks after receiving my new phone, I had a friend sitting in the back
seat of my 3000GT (if you can call it a back seat), and he said Hey, whats
this on the floor. He reached down and then said Whoah, theres a
phone back here. My long lost phone, just as mysterious as it
disappeared, had now reappeared. Ive yet to discover what hidden crevice
exists underneath my passenger seat that was able to hide the phone so well
from multiple searches. In any event, I went from having just one phone
service to now owning three phone services/phones: A Sanyo 4500, a Sanyo
4700, and about $5.00 left of Net2Phone credit.
Now if I could just figure out where I put my wallet.
Tom Keating is CTO of Technology Marketing Corporation, and the
executive technology editor of TMC Labs. He can be reached at Tom Keating .
[ Return
To The May 2002 Table Of Contents ]
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Software-based Telephony via SIP
Traditional telephony boards have provided functions such as DTMF
detection, recording, fax functionality, voice recording, and speech-rec, as
well as the DSP horsepower to drive these functions. Now, a company called
aTelo (www.atelo.com) has developed a
software-only media processor called the aTelo Media Server (aMS) that can
replace traditional computer telephony boards.
Essentially, the aMS processes media streams on the network and doesnt
require the use of specialized, proprietary CTI or DSP resources. The aMS
provides recording, playback, speech recognition, text-to-speech, DTMF, and
T.38 fax functionality by leveraging the host CPU of standard servers (Intel
Pentium or Sun UltraSparc based). It is an application-level process that
runs on top of standard operating systems, such as Windows, Solaris, and
Linux to effectively provide board-less media processing.
aMS is controlled using SIP and HTTP. This eliminates many of the details
typically associated with computer telephony development (e.g., channel
allocation, managing low-level signaling), enabling developers to use
generally available web tools (Java, ASP, Perl, CGI, etc.) and
infrastructure to build and deploy telephony applications. aMS supports VXML
2.0 as well as their own XML-based scripting language, giving developers the
ability to create a wide range of services such as unified messaging, IVR,
etc. The cost reduction advantage of using a software versus a hardware
solution is pretty obvious. I found it interesting how voice was converged
onto data networks, and now aTelo has taken it a step further by converging
complex voice/telephony applications onto the data network. Certainly, I
found aTelos software-based solution an interesting paradigm that could
have the ability to revolutionize how telephony apps are created.
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