8 posts categorized "PSTN"


Why Video Conferencing Needs a Better Story

By now we know a lot of details about why HD voice calls are better than conventional phone calls. We've heard how the PSTN cuts off much of the audio range human conversation usually employs, making it hard to distinguish between fricatives such as s and f, and to understand people with different accents. We know that straining to fill in the words and phrases we can't understand produces listener fatigue and makes conference calls an ordeal.

All this information is evidence that the HD voice promoters have done a good job of getting the word out about their favored technology. But we don't have the same kind of information about why video calling is better than voice calling. The general assumption seems to be that everyone understands the benefit of video communication intuitively. In reality, understanding is limited, because detailed information is in short supply.

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Does AT&T Really Want to Get Rid of the PSTN?

When AT&T responded late last year to the FCC's request for comment on the transition from circuit-switched to all-IP public telephone infrastructure, it seemed to mark a turning point in the history of telecommunications. The 30-page letter the telco filed on December 21 urged the total phaseout of POTS (traditional "plain old telephone service") and the PSTN (public switched telephone network) on which it runs. It also recommended that the agency set a firm date for the transition in order to ensure that it happen as quickly as possible. Thus the company whose name is virtually synonymous with traditional telephony seemed to cast a clear vote in favor of the all-VoIP future. In reality, though, it was just as much a vote against AT&T's traditional service obligations. It was also a shrewd attempt to bind the phone company's interests to the high-profile issue of universal broadband access.

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The Top 25 VoIP Advances of 2009

There were more advances than true innovations in the VoIP world in 2009. That's because some of the most important developments had more to do with commercial and political maneuvers than with technical creativity. Still, such maneuvers often helped spread the benefits of VoIP as much as did technical innovation. And collectively, the advances brought some already-evident trends into clearer focus. A key such trend is the increasing integration of voice with other applications and services. Another is the intensifying interest in HD voice. A third is the growing interconnection of VoIP services, in part in response to the possibilities that end-to-end HD voice offers. With such trends as background, here, in no particular order, are our top 25 VoIP advances of 2009.

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Google Voice-Gizmo5 Combination Means Free Inbound, Outbound Calling

TechCrunch reported this morning that Google has bought Gizmo5 for $30 million. Gizmo5 is a SIP-based Internet phone service that competes with Skype. Such an acquisition would make sense, given the already-close relationship between Google's Voice service and Gizmo5. One little-noticed effect of that relationship is that the combined services already allow free inbound and outbound calling to and from the PSTN via Internet-connected PCs with headsets. A formal acquisition would presumably make such calling even easier.

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Sprint Expands SIP Trunking Availability

SIP trunking services deliver voice calls from telecom providers to companies over IP data connections. Feeding their traffic directly into IP PBXes on the companies' premises, such services can bring considerable benefits. Sprint began offering SIP trunking to companies using Microsoft's Office Communications Server 2007 R2, an IP PBX software package that runs on Office servers, in February of this year. Now it's making the service generally available to business customers.

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AT&T Call Blocking Attack Reveals Google Voice Structural Problem

AT&T's recent letter to the FCC about Google Voice was obviously disingenuous. It tried to link network neutrality, a key Google crusade, with Google Voice's blocking of certain calls. In reality, there was little connection except the politics involved: The real goal of the communication was to paint AT&T as on the side of network openness, and Google as on the opposite side. But the letter did inadvertently bring to light a potentially major weakness in the Google Voice model: the fact that the free service has to pay to have its users' calls delivered to their destinations on the PSTN (public switched telephone network).

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Skype Adds Cisco SMB Interoperability

Skype business announcements are coming fast and furious these days. One big one was the introduction of Skype for Asterisk earlier this month. Others are the result of the introduction of Skype for SIP beta service in March. ShoreTel was the first to announce certification of its IP PBXes with that service earlier this month. SIPfoundry followed with certification of its sipXecs product about a week ago, and now Skype has added the biggest name yet: Cisco.

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XConnect and GSMA Open Way to VoIP-Cellular Interconnection

VoIP and cellular services alike can do a lot of things that conventional landline services can't. For example, they can transmit both voice and various other kinds of data between phones or other end devices. That capability makes possible all kinds interesting combined services, often starting with or based on the ability to detect users' presence – that is, their availability to receive calls or respond to messages.

Once those services encounter the traditional phone network, or PSTN (public switched telephone network), though, they hit a roadblock. The PSTN can transmit only voice calls and limited kinds of call-related data. That means presence and other information, not to mention the various kinds of video or other data streams themselves, can't get through. A new deal between XConnect and the GSM Association, or GSMA, attempts to circumvent that roadblock.

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  •     A selection of free documents for download to help make purchasing decisions when shopping for a business phone system.
  •      Get customized price quotes on a business phone system from top vendors.


  • Choosing the (Near-) Perfect Cloud Video Conferencing Solution
         This 7-page buyer's guide gives SMBs the information they need to choose the cloud-based video conferencing service that fits their needs. As a for-purchase download priced at $9.99, this document avoids the conflicts of interest of papers and guides that are offered for free, or sponsored by, vendors and service providers. Instead, it provides the kind of objective and authoritative information that would otherwise require assigning a staffer to spend days or weeks searching out and evaluating.

  • SMB Video Conferencing: Getting Beyond Clouds & Interoperability
         This 31-page VoIP Evolution report provides an in-depth analysis of a market that has suddenly become very competitive. It identifies and dispels some of the misconceptions that have become part of the conventional wisdom surrounding SMB video conferencing. Chief among these are unrealistic expectations regarding the cloud approach and interoperability.
         The report provides an innovative approach to analysis by illustrating that these issues are just two of many important factors that differentiate solutions from one another. The report surveys 10 Companies to Watch and compares 16 cloud solutions using a unique Differentiation Matrix that clarifies their strengths and weaknesses.

  • Voice Over LTE: More Pitfalls Than Promise for Now
        This 18-page Heavy Reading Insider report, written by Robert Poe, analyzes the prospects for delivery of voice calls over cellular networks using LTE (long-term evolution) 4G wireless technology. Operators are originally looking to use LTE mainly for mobile data services, since a number of technical issues make delivering voice traffic over LTE complicated. The report describes the various options available to operators, and explains why they are likely to move to voice over LTE later rather than sooner. Information about the report is available at Heavy Reading 4G/LTE Insider.

  • Making HD Voice Happen: Choosing Codecs, Connecting Islands
        This Heavy Reading Insider report by Robert Poe evaluates the impact HD voice will have on voice services providers ranging from traditional telcos to cable MSOs to cellular carriers to VoIP operators. The 20-page report also analyzes the role vendors' and providers' choices of codecs will play in ensuring that HD voice services can be delivered end-to-end, rather than only within individual providers' or enterprises' networks. It also surveys the HD voice efforts of 14 vendors.
        Information about the report is available at Heavy Reading Insider. A column about the report is available at Light Reading.

  • Disruptive VoIP Services: What Carriers Need to Know
        A report by Robert Poe for Heavy Reading, analyzing the innovative VoIP services with the most potential to disrupt the telecom services market over the next three to five years.
        The 57-page report describes the changes VoIP innovation brings to telephony models, practices and concepts. It identifies 17 categories of potentially disruptive VoIP services, and analyzes their potential impact on the market. It also profiles 50 potentially disruptive companies and services.
        Information about the report is available on the Heavy Reading Website. Coverage of the report is available on the Light Reading Website.

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