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WHITE PAPER Having It All: An Audio Conferencing Strategy for Networks in Transition WHITE PAPER Having It All: An Audio Conferencing Strategy for Networks in Transition WHITE PAPER Having It All: An Audio Conferencing Strategy for Networks in Transition Overview But it was unavoidable that this continued pressure to stretch the built-in constraints of POTS and PSTN would lead to the development of wholly new kinds of endpoints and ways to connect and network them, and that is the situation facing any IT manager or audio conferencing buyer today. We’re now positioned at a time where there are numerous attractive new options for phone connection, while many of the old systems are still in place and working. Hosted and unhosted alternatives are proliferating, and customers are looking for ways to ensure that changing a network or a service vendor next year won’t mean scrapping all those equipment investments as well. Alternatives in the universal network Cellular network But POTS is far from alone these days. With the rapid growth of wired and wireless technology, we are seeing an increasing range of options to move beyond the POTS connection. Taken all together, they form a kind of “universal” network in which there is some element, somewhere, that can support almost any capability imaginable. This is often a good thing, but each of these options also has its own distinctive strengths and weaknesses. This profusion of choices can make a selection difficult. • We sacrifice a lot for that independence. The unreliability of a cell phone connection, for one thing, is so ubiquitous as to have lost its novelty even as a topic for comedy. This paper will review these different alternatives, look at their advantages and drawbacks, and offer some suggestions as to how an organization can position itself for the future while continuing to make the most of its existing investments, and how that organization can continue to benefit from the stability of what is working today. The newest part of the “universal network” comes from the use of IP (Internet protocol, or just “Internet”) for telephony. Because IP carries data regardless of its meaning, that data can represent anything, from voice to video, graphics, entertainment, messaging, status information, data files…but why am I telling you what data is? When it’s used for voice, VoIP (Voice over IP) telephony offers a different set of advantages and disadvantages. A revolution is occurring in company telephone networks today. They are moving from older POTS and proprietary digital plans to IP, and this can make it hard to decide how to make the ongoing investments that keep them running. In this paper, we consider the different alternatives, and how the inclusion of multiple network abilities in an audio conferencing device can assure both excellent performance and investment protection. Introduction For decades now, telephony has been slowly awakening from Alexander Graham Bell’s analog dream of a wired narrowband audio service, to a host of agile communications abilities. But any change that affects billions of devices is a big change, and big changes never happen all at once. The evolution of voice and video communications is not happening at one time or in one place, so the solutions we select need to work across an unprecedented breadth of networks and environments. “Phone connection” has had twin meanings for a long time, but we are now comfortable with the distinction between how a phone is connected to the wall, and how a conversation is carried around the world. When we talk about the PSTN, or Public Switched Telephone Network, we’re referring to the massive and mature worldwide structure that lets us connect any one telephone to another. POTS, on the other hand, as Plain Old Telephone Service, is more often used to refer to the analog subscriber loop or twisted-pair hardware connection: that single pair of wires on which two-way audio is melded with dialing, presence, hook status, other signaling, and DC power to form a specific hardware interface to an endpoint. Connecting POTS telephones to one another through the PSTN network has long been one of the simplest and most common configurations, but the 20th century saw rapid growth in the varieties and capabilities of phone systems. Analog, and later digital, proprietary PBXs routinely discarded the old POTS interface for a direct customized phone interface, allowing them to add new features and manage costs while still connecting through the PSTN for longer-distance connections. As time went by, POTS and the PSTN were able to provide new abilities such as facsimile (initially analog, later digital), and even the direct transmission of computer data (in which, once the theoretical limit of 3200 bps was reached, we developed new theories and boosted this to 56000 bps over the very same networks, and then to 4 Mbps and higher by more finely parsing the meaning of “network”). 2 PSTN: Still here for a reason Millions of telephone connections are still secured by twistedpair POTS interfaces. Many enterprises have plans for VoIP and UC conversion, but even enterprises that have enthusiastically changed over their entire telephony backbone still hold on to a competent number of POTS connections. There are some very good reasons for this. POTS remains the unchallenged champion when it comes to reliability in communications. When someone says “five nines,” we don’t think of a free Internet phone service, we think PSTN. Carriers have spent a century buttressing this powerful, multiply-redundant network, and it has become legendary for its invariant ability to connect its network-powered endpoints under almost all circumstances. The PSTN is highly tolerant of abuse and misuse (a characteristic which is one advantage of setting low expectations and then exceeding them brilliantly). Some of the first phone systems were private networks, running from farm to farm over wire fences, and this kind of broad-mindedness in defining an architecture can be a real benefit when dealing with widespread geographies and changing environments. And, of course, the PSTN is here already. Costs are already sunk, the troubleshooting has been troubleshot, and analog telephony is in place and working worldwide. Complex issues of interworking among networks worldwide have been long solved, yielding a system that works reliably among endpoints everywhere. VoIP and open SIP • Since VoIP is carried over the IP network, no separate network is required as there is with POTS or wireless • Because the nature of the data is transparent to the network, no inherent restriction exists on the abilities that can be implemented • Digital communication lets noise be quantified rather than encountered haphazardly. On any reliable network, noise and distortion is carefully apportioned, most often as part of a tradeoff between data bandwidth and sound quality • The emergence of high-efficiency, high fidelity open standard audio codecs has enabled extremely high-quality audio and video on conventional data networks at low cost. • Anywhere IP goes, VoIP can travel. Since IP is carried over a wealth of wired and wireless media, VoIP has enormous reach, often extending to places where even cellular phones cannot connect. • Among the challenges is the fact that many VoIP networks are still fairly isolated. Even today, a VoIP phone on one network often cannot dial directly to a VoIP phone on another without both networks passing their traffic through— you guessed it—the narrowband PSTN. • Another VoIP issue is that phones must be properly registered and configured or they don’t work. While a POTS phone will plug in and get a dial tone if the jack is live, carrying a VoIP phone to another facility or even another subnet within the same building can be an uncertain proposition. • One other thing about VoIP is this: for organizations of all sizes, the transition to VoIP takes time, and new systems overlap the old. It’s not uncommon to find buildings in which some rooms have extensive VoIP connectivity while others have simple POTS connections and (non-VoIP) Internet jacks. • The cellular phone has transformed our conception of being “connected” by letting us stay in touch from vastly more places than is possible from wired (or wireless VoIP) phones. • Sound quality on cellular phones is another accepted compromise. Cell phones have traditionally sounded muffled, squawky and a fine conduit for any airport public-service announcement that drifts by. It’s interesting how, with its limitations and drawbacks that directly contradict any philosophy of “five nines,” the cellular phone is still almost universally welcomed. When cell phones work, they add a vital link to locations and settings that can be untouchable otherwise, and that versatility has enormous value in almost any application. Proprietary VoIP A constantly-shifting range of specialized proprietary and open-source systems are available for telephony over IP today; a quick look at Wikipedia reveals more than 40 distinct VoIP systems available for use (look under “comparison_of_ VoIP_software”). These systems vary widely in capabilities, licenses, scope, encryption, compatibility, performance, and so forth. There are many explanations for these differences, but one consequence is a continuing explosion in incompatibility, even among VoIP systems. Workplaces It used to be that the telephone’s place was on the office desk, the speakerphone’s on the conference table. This is still sometimes true, but there’s been a proliferation in workplace types that is throwing phones into a host of new and often challenging environments. This shift in work styles is happening for a number of reasons: new perspectives have emerged on how work can be done in facilities; definitions of facilities themselves have become less “traditional,” and the number of remote workers and remote workgroups is growing enormously. Consequently, a business audio teleconference may have participants from almost anywhere: a group of people sitting together in a big, loosely sketched cubicle area; a couple of workers in home offices; a surgical team in an operating room; or an open space in the stockroom of an offshore oil drilling platform, just to suggest a few. 3 WHITE PAPER Having It All: An Audio Conferencing Strategy for Networks in Transition WHITE PAPER Having It All: An Audio Conferencing Strategy for Networks in Transition Physical hosts Dependable performance At the same time as conference places are changing, what is used as conference devices is expanding, as well. Today, cell phones and laptop computers are often pressed into service as speakerphones, while earbuds make “hands free” possible with no loudspeaker at all. But these stand-ins often don’t work as well as we think. We all know from long experience that those on the other side of a phone conversation will gallantly tolerate even the worst corruption and noise without commenting unless they absolutely cannot hear what’s being said. Rather than asking “can you repeat that,” listeners commonly let it go, gradually falling out of the discussion completely. Telephone priorities on the universal network Change in how we communicate today is the rule, not the exception, and businesses must continue adapting and investing in spite of all these shifting winds. Given the speed with which networks are being created and evolved, and the expanding ways in and places from which people are doing business, it’s worth taking a new look at what priorities apply when choosing an audio conferencing system. How important are the characteristics we valued yesterday? And what is essential today that was unheard of yesterday? As it turns out, there are two broad priorities that come out on top: versatility and reliability. Versatility Where it’s used It’s hard to predict precisely where a particular system will be installed. This means that an audio conference system has to adapt to a wide range of acoustic environments: a key participant in an important meeting can call from anywhere--from a full-sized conference room to a small office, a cubicle, and even an open area in the middle of a building. Ventilation grilles, computer fans, tapping keyboards, bad room acoustics, and people sitting everywhere from up close to the back of the room and even nonparticipating passersby are all part of the challenge that an audio conference system must handle flawlessly. Multi-network connectivity As organizations shift among different service vendors and network formats, the most important response by audio conferencing systems must be that they keep working. A system may have been planned as part of a SIP network but then be unexpectedly needed in a session over AOL, Blink, or ZPhone. A planned Skype video call may run afoul of a firewall and the only option to have the meeting is to use that POTS jack nearby or to cluster around the one working cell phone in the room. Further, there’s no guarantee that the service in 4 place today is what IT will find optimal tomorrow. It wasn’t that long ago that it would have been unimaginable to question whether a phone could plug into the phone network, but today the question is not whether there are a half-dozen active networks, the question is which network shall we use for this particular meeting? Equipment pools Most organizations don’t want to pay for a permanent conference phone at every single wall jack. One common solution is to maintain one or more centralized pools, dispatching devices like audio conferencing systems at need and then re-collecting them after meetings are completed. This approach puts a higher emphasis on the need for a sturdy, reliable solution for several reasons: • Uncertain wall jack. There’s only one chance for the “speakerphone from the A/V pool” to work wherever it’s delivered. Because networks are always in flux, the chances of a working connection are much higher when more than one kind of connection is supported by the traveling system. Incorporating multiple network interfaces in audio conferencing systems to be dispatched ad hoc makes a business more robust, regardless of the preferred network. • Sturdiness. Some conference systems are moved two or three times a day: unplugged, dropped on a cart, wheeled to another floor or another building, and thrown onto a table or a counter in front of an unforgiving audience. Equipment isn’t coddled like fine china, and it has to be built to meet this kind of casual treatment. • Power. The destination may have an AC power jack somewhere, but that doesn’t mean there’s one nearby or available. A unit that can accommodate both power over Ethernet (PoE) as well as AC power means that the destination doesn’t need to be near both an AC jack as well as an Internet jack. Future proofing A lot of organizations are still in a transitional state when it comes to their telco networks. “I know what I want us to do, but we haven’t done it yet” is a common remark we hear. Networks may be partly VoIP and partly POTS; some may even still be proprietary digital throughout, using terminal adapters for devices like fax machines and conferencing systems. Trapped in this in-between state, their managers are reluctant to purchase new POTS equipment because they know they’re moving toward VoIP although they may not know exactly when. These managers are torn between conflicting requirements. A new conferencing system has to hook up and work in the network as it exists today, yet continue to work as well, or better, whenever the new network arrives. When a conferencing system can connect to a variety of networks, one challenge is that each network usually has different strengths and shortcomings, as mentioned above. Conventional PSTN telephony, for example, doesn’t support HD Voice, while the VoIP networks which do sometimes suffer from degraded reliability due to connection problems, dropped packets, and other causes. “Jack of all trades but master of none” isn’t acceptable behavior for a piece of core communication technology; it has to be a top performer on every interface, understand the strengths and weakness of each, and configure itself accordingly. Failover When a telephony network goes down before or during a conference call, a common response is confusion: people suddenly find themselves trying to be their own IT specialists, figuring out what happened, where it happened (Is it working at this end? Did the other end hang up? Is the network down?), what to do about it (Is there another room? Do we have a speakerphone that can plug into this other jack?), and taking action (Does anybody have Pamela’s landline number?). The preferred behavior is one in which an endpoint can implement its own “Plan B,” by taking advantage of the fact that most locations have more than one separate network available, especially in conference rooms. Automatically switching to a PSTN connection on loss of VoIP (or vice versa), and back again on recovery, is a quick and easy way to re-establish a call across a backup network and keep the conversation going. Transparent speech Supporting HD voice as well as narrowband, implementing multiple codecs and open standards, and building-in inherent resistance to network problems and poor acoustic environments are basic requirements of an audio conferencing system. These help assure that whatever new capabilities come with a system upgrade, the conference unit will be ready to take advantage of them. Simple operation and configuration A number of past-generation telephony systems became infamous for their complexity of configuration and difficulty of use. Nobody expects to need an instruction manual to place a phone call, so an endpoint, especially one shared among assorted users, has to be elegant and forgiving in its operation. Open standards An important aspect of reliable operation is the ability for everyone to be able to access the same methods of communication. This applies to everything from the use of openly available protocols and standards such as PSTN, SIP, LDAP and a host of others; G.711, G.722, and multiple other common audio codecs; and to a the use of simple and common user interfaces. Connection independence A system needs to adapt to a wide range of requirements when connecting via multiple networks. VoIP approaches DTMF signaling differently than POTS, for example, and caller ID and directory services work differently in different countries and over different networks. Working well over multiple networks doesn’t stop at the dial tone; all essential functions have to be tuned to meet the requirements of each network. Single system, multiple networks: The Polycom® SoundStation® Duo The Polycom® SoundStation® Duo solution is the first in a class of audio conferencing systems that is designed to deliver the best from multiple network connections: VoIP, PSTN, audio, and cell phone. The philosophy behind the creation of the Duo is unique, and embodies the two major principles detailed above: versatility and dependable performance. • A s a VoIP conferencing system using SIP, the SoundStation Duo phone supports superb speech clarity with Polycom HD Voice™ technology, and defends against erratic data networks with packet loss concealment, adaptive jitter buffers, and low-delay packet transmission • When connected using its POTS interface, the SoundStation Duo solution is a robust, reliable conferencing system that supports multiple caller ID protocols and is compatible with specialized network requirements, ringer responses, and line impedances worldwide. • Connected to a network through a user’s cell phone, the SoundStation Duo phone brings full-duplex, whole-room coverage to whatever cellular network the user chooses. By leveraging the user’s own wireless connection, the SoundStation Duo phone is instantly localized, and adds a professional full-duplex room conferencing capability to any cellular network regardless of region or country. • And by connecting the SoundStation Duo phone using a host computer’s audio interface, virtually any specialized or custom protocol can be supported, from common systems like Google Voice and Skype to the arcane and highly specialized protocols used in some demanding environments. Most locations still have PSTN connections available and this is especially true in conference rooms. Because the SoundStation Duo phone can automatically failover to a PSTN connection on loss of VoIP (and back again on recovery), it is quick and easy to re-establish a call across a backup network and keep a conversation going. 5 WHITE PAPER Having It All: An Audio Conferencing Strategy for Networks in Transition Conclusion Change happens in stages more often than it happens all at once. Plans get delayed or what is sometimes worse, they unexpectedly fall into place without warning. So while it’s possible to be fully prepared for network changes, and it’s easy to hold off spending on new capabilities until just when they’re needed, it’s hard to do both. That’s why the Polycom SoundStation Duo solution is such a compelling proposition. The SoundStation Duo phone makes Polycom group audio available to all networks, so it provides extraordinary leverage of an organization’s communications investment. By building around a transparent Polycom HD Voice audio conferencing core, and supporting it with a clear multilingual graphic UI, simple configuration, and easy support, the SoundStation Duo architecture brings these critical communication elements to any communications network. When a network changes, users aren’t confronted with a whole new system and this yields another savings in time and convenience. One of the most critical needs we ask of an audio conference system is the simplest: it should stay out of the way, and let users get on with business. The SoundStation Duo solution delivers this experience by connecting transparent interactive conversation from whatever room or space is being used, over whatever network is most convenient. A versatile and top-performing solution, integrated with a robust Plan B, is a pretty good match to most network requirements. About the author Jeffrey Rodman, Co-Founder, Fellow, Polycom, Inc. Jeff Rodman is focused on ensuring the best and most transparent human communication experiences over local and remote connections. Prior to Polycom, he led definition and development of innovative new media products in roles including PictureTel‘s first engineering director and digital video products for the Broadcast division of Harris. Jeff holds an MS and a BSEE cum laude from CSUN, and has written numerous articles, songs, and one musical. He frequently speaks on topics of communications and media, being consulted when the topic turns to telepresence and HD voice technology. About Polycom Polycom helps organizations unleash the power of human collaboration. More than 400,000 companies and institutions worldwide defy distance with video, voice and content solutions from Polycom. Polycom and its global partner ecosystem provide flexible collaboration solutions for any environment that deliver the best user experience and unmatched investment protection. Polycom, Inc. 1.800.POLYCOM www.polycom.com Polycom Asia Pacific Pte Ltd +65 6389 9200 www.polycom.com.sg Polycom EMEA +44 (0)1753 723282 www.polycom.co.uk © 2015 Polycom, Inc. All rights reserved. Polycom®, the names and marks associated with Polycom’s products are trademarks and/or service marks of Polycom, Inc. And are registered and/or common law marks in the United States and various other countries. All other trademarks are property of their respective owners. No portion hereof may be reproduced or transmitted in any form or by any means, for any purpose other than the recipient’s personal use, without the express written permission of Polycom. 18234-0515