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Have you tried making a
phone call over the Internet yet? It's been possible, if not always a
piece of cake, for more than two years. I became mildly interested in
the spring of 1997, then got really into while researching several
articles (for PC World, Newsweek and MicroTimes. I'd like to share what
I've learned.
First, you should know the difference between
conventional and Internet telephony. Conventional telephone networks
use circuit switching. When a call is placed and answered, a circuit
opens. The circuit remains open as long as the call lasts, so that line
is tied up during that time.
Internet telephony employs packet switching,
which breaks up data into small packets which co-mingle on the same
line. Packets contains identifiers, address of where it came from and
where it's going, so they can be sorted, routed and reassembled at the
delivery point. When a packet is lost or corrupted by line noise, a
duplicate packet is sent.
You've come a long way, baby!
Internet telephony has come a long way since
its birth in 1996. Experts differ, however, on whether it's destined to
be a child prodigy, or a communications stepchild, stunted by politics
and efforts of the giant telephone companies (telcos). Other problems
include current Internet bandwidth restrictions and lack of product
compatibility.
Software-only products allowed hard-core
users to make the first free long-distance Internet phone calls. I used
VocalTec's Internet Phone software for my first Net calls in early 1997.
It was a free download and easy to install, but results were so-so.
Making sure we all had current copies of the software and setting a
mutually agreeable time to be online required mucho e-mail. Times delays
were a nuisance and sound quality ranged from fair to barely
intelligible at times. I couldn't see any viable business use for the
technology at the time, and personal calls were cheap enough in
off-hours or on weekends so that Net phoning wasn't worth the hassle.
Improved software and new hardware available
solve many of the earlier problems. I acquired samples to check their
effectiveness.
The Hardware Varies
The hardware I checked included Internet
PhoneJACK, InfoTalk and Aplio Phone, all different but representative of
currently available Net phone equipment. Software used included the
latest version of VocalTec's Internet Phone, Microsoft's Net Meeting and
IDT's Net2Phone. These were not objective, scientific tests,
understand; just quick, subjective trials to see how the results
compared with my earlier software-only Net phone calls and those I make
every day using conventional phone service.
PhoneJACK is a Plug-and-Play DSP (digital
signal processing) card that plugs into an ISA slot (half or full). It
works alongside, but independently of, existing sound cards. It doesn't
need a modem, and doesn't use a precious IRQs. It does include an RJ-11
POTS (Plain Old Telephone System) port, RJ-12 headset port and 3.5mm
connections for microphone and speaker. Its hardware-based compression
technology reduces delay and CPU load on your system.
You can connect a standard phone to the
PhoneJACK card and enjoy sound not too different from conventional
phones. It's ideal if there is another PhoneJACK on the other end of the
call, but that's not necessary. Even if the other party is only using
such software as NetMeeting or Net2Phone, both parties benefit from
PhoneJACK's better sound.
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InfoTalk and Aplio/Phone,
Net telephony devices from InnoMedia and Aplio, Inc., differ markedly
from PhoneJACK in that they do not require a PC. Both plug in between a
conventional phone and POTS wall outlet, serving as a mini-gateways to
the Net.
They have two drawbacks. They use proprietary
technologies, so parties on both ends of a call must use the same
products. An InfoTalk phone cannot talk to an Aplio/Phone, or to any
other IP Telephony device. Also, making a call is not as simple as just
dialing a number. That's just the beginning.
After you dial and the call is answered, with
InfoTalk, you tell the other party you want to make this an Internet
call. Either party can then press the pound (#) key to initiate the
Internet connection. When the connection is established, you can begin
the conversation.
With Aplio/Phone, after making connection,
either party can press the "APLIO" button on the device to switch the
call from the long-distance carrier to the Internet. Both parties then
hang up; in about 45 seconds, the phones ring and callers can converse
as usual. Only they're doing it on the Internet, not with AT&T's or
MCI's meter running.
So that's the current state of the art. The
three approaches -- software only, DSP cards and standalone devices --
have drawbacks, but I lean toward the PhoneJACK as the best solution for
my purposes at this point. All hardware IP Telephony products have one
thing in common, however. They're pricey, from about $200 to $300,
compared to standard phone instruments that now go for as low as $20.
How many long-distance calls will it take to amortize the cost of a Net
phone, especially if you have to supply the devices to some of the
people you call regularly?
The lack of interoperability looms as an
immediate threat to IP Telephony. It reminds me of the bad old days
(late 1970s, early 1980s) of proprietary operating systems, including
CP/M and DOS. Microcomputers could not talk to each other any more than
an InfoTalk can to an Aplio/Phone. It wasn't until standardized
operating systems came along that micros began selling in respectable
quantities.
I doubt that lack of standards will continue
too long, however. Some corporations already use their WANs (Wide Area
Networks) for communications via TCP/IP, using the new Voice Over
Internet Protocol (VOIP). The audio quality has been likened to that of
cell phones, which is good enough for this purpose. And the savings in
this context can be significant.
We also have the H.323 standard, which
defines a common set of compression/decompression algorithms. Pushed by
such biggies as Intel and Microsoft, H.323 is gradually being accepted
by IP Telephony vendors. Its champions say it will do for Internet
telephony what SMTP (Simple Mail Transfer Protocol) has done for e-mail.
On the debit side is the full-court press by
the giant telcos to stifle development of Internet telephony,
considering the big political guns they can bring to the task. They
claim that if Net phone calls were subject to the same fees as they are,
there would be little or no savings.
That remains to be seen. It might be true for
large companies with enough telephony volume to get rates of a few
cents per minute from the telcos, but probably not for individual and
small businesses.
Summing up, most experts believe that
Internet telephony future looks promising. I predict many of us will be
making at least some of our phone calls over the Net within two to three
years.
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