Evan,
>>I was wondering if the evaluation parameters that were discussed would be evaluated at only the beginning of a call or when each individual packet is sent.<<
By its nature, the adjustments would be dynamic, but not necessarily packet by packet, since it takes several packets to make a usable sampling to analyze. Afraid that I don't have the specifics on this handy, but I would surmise that it would be a time-averaged treatment, looking at very short term (almost instantaneous) performance, and very short-interval trending patterns, and adapting to those conditions accordingly. [[Atin, can you clarify this for us?]]
>>I wonder what the future of 'smart-routing' will be. Which data pipes are used at what time, etc. to route IT calls more efficiently and effectively.<<
Increasingly, the ITSPs who provide service level assurances (still yet to be defined, for the most part) will use private IP backbone nets (or public Frame Relay networks where they are more extensible, internationally, in particular), for the majority of their high density routes between routers and switches.
These private-like nets may be proprietary (owned, or of an indefeasible right-of-use type) or they may be tunneled pipes on VPNs now being offered by xSPs <?> such as Concentric, BBN, and most recently, by AT&T.
Or they may be any high capacity cloud that can guarantee a pre-defined level of quality of service (QoS) assurances, as opposed to subjecting the VoIP application to an inordinate number of hops and congestion over the greater Internet, both of which adversely affect latency, hence, call quality.
By keeping the VoIP separate in this fashion, providers can more accurately predict bandwidth availability and utilization, and route traffic loads more intelligently, preserving high-quality conditions. Actual paths can be further defined in accordance with policies and QoS statements as they are written into the ITSPs routing tables and filters for specific users, as specified by the user-ITSP service level contract.
Also, the paths may be selected in a dynamic way in accordance with Advanced Intelligent Networking call procedures if there is a cross-over of domains, i.e., if "contamination" is introduced by the PSTN side, as in the case of call waiting, follow-me services or time-of-day features, etc., that are a part of the user's larger switched-service account profile.
In the end, users will NOT want to deal with two service profiles, i.e., one for POTS and one for VoIP. Rather, they will depend on their service provider to mend the differences in a transparent way for them. Remember the use of alternative carrier "automatic dialers" not so long ago? These were replaced through the use of 1+ intelligence in the PSTN which directed calls to the appropriate carrier through pre-subscription features. We'll see this in the VoIP arena soon, if it hasn't been done already, as opposed to having to call a node, entering a PIN and so forth. The instructions that will support this (and other least cost routing features) will not _necessarily_ reside in the ITSP's database, rather it may also in part reside with the PSTN carrier(s) and their universal signalling system 7. Cross-over, again.
>>I can foresee the development of even more sophisticated data traffic software that will be used to monitor data flow and route the calls around any potential problems.<<
This is, in essence, the beauty of TCP/IP and one of the reasons for its initial development as a fail safe network for the government (ARPAnet). However, and I won't dwell on this here, the fact that security holes exist on the Internet has never really been stated strongly enough, and I am beginning to see a great deal of clinical level denial about how truly porous the whole thing actually is. This, too, will lend impetus to the ITSPs use of private-like ("off-net") facilities wherever they can. After a hundred plus years of solid voice quality performance supplied by the LECs, upstarts now find themselves with a hard act to follow, at least where audio quality and time-sensitive delivery is concerned. Private IP backbones and VPNs are one way to assure that they at least have a chance. Sed'nuf.
>>also if you could post a link to the full article for InnoMedia, I'd appreciate it.<<
I no longer have the link you're asking for. I think I deleted it inadvertently, but they have a web site at innomedia.com which includes PRs, that you may want to investigate.
The following article is one that I thought might interest you. It can be found at Tech Search:
192.215.107.71
It in some ways supports the issues that I've raised above.
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IP Telephony Takes Off
(12/05/97; 10:00 a.m. EST)
By Matthew Friedman, TechWeb
Dismissed earlier this year as technological whimsy, IP
telephony products are now being introduced with a
frequency bound to capture IT managers' attention, if
not their purchase orders.
Lucent Technologies will unveil next week software
for voice over IP conferencing, and Vienna Systems
will launch a new IP telephony network service. And
voice processing vendor Clarent is preparing a
strategic marketing alliance with Microsoft.
Lucent Technologies' Elemedia division is building the
foundation for IP conferencing with its CX1000S and
CX2000S software modules. Lucent will make the
modules available to other vendors developing Internet
voice-conferencing applications.
"Right now, IP telephony products are point-to-point,"
said Elemedia president Joe Mele. "Software that uses
our components will be able to enable conference calls
that are as high quality as point-to-point calls, but with
large numbers of participants."
While Mele said that conferencing is a fairly simply
matter using pulse-code modulation telephony, IP
creates some unique challenges. The biggest hurdle is
conferencing together multiple compressed voice
feeds, with acceptable quality in real time.
Both modules will be available to developers in the
first quarter of next year, and Mele said he expects
other vendors to begin shipping products by next
summer.
In an effort to leverage its line of IP telephony
hardware, Vienna Systems will announce next week a
partnership with Boston-based IP telephony service
provider VIP Calling to deploy a global IP telephony
network.
"Private networks are so much more efficient as a
transport medium," said Kerry Hawkins, Vienna's vice
president of sales and marketing. "In the short term,
this kind of virtual private network is necessary for IP
telephony, so it's necessary for us. Standards aren't
widely available or deployed, so you need
single-vendor networks to make it work."
Zona Research analyst Barbara Ells agreed and
pointed out that, by creating a specialized virtual
private network, Vienna is, in effect, creating its own
market.
"There are a lot of infrastructure problems with IP
telephony that have to be ironed out before it really
works," Ells said. "Everyone keeps talking about the
Internet as if it's one thing, but there are a lot of
different pieces that do different things, and there will
have to be specialized resources for IP telephony."
Meanwhile, Clarent and Microsoft had planned to
unveil a strategic alliance for the cross-promotion of
each other's products next week, but they put the
announcement on hold to iron-out last minute details.
Under the deal, Clarent is expected to promote
Microsoft's NetMeeting collaboration software and
integrate the International Telecommunication Union's
H.323 standard for IP-based conferencing into its
gateway product so it can communicate with
Microsoft software.
According to Ells, Microsoft is testing the IP telephony
waters through the alliance.
"Contrary to what Bill Gates might say, Microsoft just
wants to be in every business," Ells said. "NetMeeting
already has some voice-over-IP capabilities, and it's
normal that Microsoft might want to expand on that."
===============
Hope this helped, Frank
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