Review: Voice over IP Systems

If you're in the market for a VoIP system, our Editor's Choice, with its excellent presence application and conferencing system, not to mention its affordability, might be what you're looking for.

June 24, 2004

18 Min Read
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One enticement of voice over IP is that it lets you offer productivity-enhancing applications, such as unified messaging, presence and telecommuting. We've seen these features in high-end, enterprise VoIP systems and wondered if smaller deployments (with matching budgets) could get the same functionality. So we crafted our RFP around a modestly sized fictional company, HaveNoFear Insurance. We required that the responses support ACD (automatic call distribution), telecommuting, unified messaging and presence. Phones had to support the 802.3af PoE (Power over Ethernet) standard with two 100-Mbps ports and QoS (Quality of Service). We also made clear that cost was an important factor (see our scenario for more details).

We invited every voice PBX and VoIP provider we could scare up and received solid proposals from Alcatel, Avaya, Interactive Intelligence, Nortel Networks, ShoreTel, Siemens and Zultys. Cisco Systems declined to participate.

We were excited to find that some advanced features are offered in systems for small enterprises. And not only did the vendor proposals meet our minimum requirements, but they all demonstrated that VoIP has advanced the state of communications. All the responses offered conference calling and voicemail in the price (for a list of must-have features, see "Checklist of Basic Features,").

We weighted cost at 30 percent for scoring purposes (see our report card). This is a heavy weighting, but based on recent conversations with readers in small business IT shops, cost is an overriding concern. Many enterprise departmental branch-office deployments also must adhere to strict budgets. Remember, too, that prices for these types of products are negotiable.

Even though a vendor might emerge as a favorite based on its RFP response, that can change later your decision-making process. Here are the steps we'd recommend to narrow the field:

• Make time to contact the vendor's reference customers.

• Take a good look at each vendor's management interface to determine how easy (or not) it will be to maintain the system.

• Check out local-support availability, since these products usually are installed by resellers, especially in small cities.

• Ask for demonstrations and make sure the product does what you want it to do without imposing limitations on the way you do business.

Checklist of Basic Features Click to Enlarge

Viable VoIP

We'd be hard-pressed to eliminate any of these vendors based on their responses, though it's tempting to toss those without SIP (Session Initiation Protocol) support. But we didn't, because we didn't specify SIP support as a requirement, despite our well-documented partiality for standards compliance. Given that this is our first look at lower-priced VoIP systems, we decided to judge products strictly on their functionality. The next time we do a VoIP RFP, we likely will mandate SIP support, since these systems will give you more phone options, as well as better integration with and more choices for third-party applications. Note that the proposals from Interactive Intelligence and Zultys are pure SIP.

Based on the responses, Siemens' HiPath 3000 IP System earned our Editor's Choice award. Its price is easy on the wallet, and it has an excellent presence application, is a full-featured PBX and has the best conferencing system of those we reviewed. The full vendor responses to our RFP can be found online here.


Siemens' proposal was the least expensive, at $84,134 including all the basics and more, especially in terms of presence. Siemens also has the widest codec selection for both its basic and executive phones, which support the G.711, G.729 and G.723 codecs (see "VoIP Codecs,"). All three codecs are also supported with VAD (voice-activity detection) with silence suppression. This feature can cut bandwidth utilization by transmitting data only when speech is present.

Siemens was the only vendor to point out that it inserts "comfort noise" locally to make up for the background noise not transmitted during silence suppression. This is good--most people use background noise as a cue that they're still connected. Siemens also has some of the least expensive phones, proposing the optiPoint 410 for both basic and executive-level phones for $182.50 each including software. This helped keep the total cost of its system low. However, the vendor also proposed this model for conference phones, and that hurt its phone ratings in relation to rivals that proposed Polycom's conference phone, which has become the industry reference.

Unfortunately, the HiPath 3000 switch line requires proprietary phones, and Siemens did not indicate any planned support for SIP-based phones. On the bright side standards-wise, Siemens' OpenScape SIP-based presence product is one of the most impressive of the bunch.

Based on Microsoft's Real-Time Communication (RTC) server, OpenScape lets users automatically advertise multiple levels of status and availability over the phone, instant messaging or e-mail. It also lets users easily set up rules for contacting them, update their current contact status and specify which devices should be contacted, in preference order or if at all, depending on who is calling (for a presence primer, see "The Basics of Presence,").

Vendors at a Glance Click to Enlarge

For example, you can choose from statuses like "on the phone," "in a meeting," "on vacation" or "available via cell phone." And the status information can be integrated with groupware applications, including Microsoft Exchange, IBM/Lotus Domino and Novell GroupWise.

The HiPath 3000 comes with a basic conferencing system, but HaveNoFear could add on the OpenScape presence application, which brings presence to conference-call setups. This makes it much easier to set up ad hoc conference calls, especially with predefined groups also running OpenScape. And it makes it possible to turn a standard conference call into a multimedia collaborative workgroup session with a few mouse clicks.

Siemens' unified-messaging application offers high levels of integration with Microsoft Exchange and Lotus Domino, including the ability to listen to, delete and forward e-mail messages from the phone. Novell's GroupWise and Internet-based e-mail are supported, too, but with less integration. Our only real nit here is with the absence of IVR (integrated voice response), which lets users manage messages hands free.

HiPath 3000 Real-Time IP System 4.0. Siemens Information and Communication Networks, (800) 765-6123, (703) 262-2000.

We like Avaya's phones, both the basic and executive models. All include VAD for G.711 and G.729 and, notably, AES encryption. The executive speakerphones have many of the hard-key feature buttons we looked for--conference, transfer, redial, mute and hold. Avaya also included a high-quality, omnidirectional, disc-shaped conference phone that looked a lot like Polycom's. We were impressed that Avaya's phone-management utility allows for setting up one phone or a group of phones simultaneously and could let us schedule such operations in batch mode so that upgrades could be completed off hours.

Avaya's setup had all the basic PBX features except automatic camp-on, a nicety made somewhat obsolete when presence is implemented. Avaya split the PSTN access trunks across two G700 gateways so that if one failed, half the trunks would survive. The company also said that for $2,000, the S8300 call controller could be made redundant. This seemed like a small price to pay. One feature Avaya offers that none of the other vendors mentioned is extending the office phone features to a cell phone.

Avaya also touted its SIP support, which it says will extend to SIP telephony endpoints and other communications services. Although we liked Avaya's talk of SIP support, we'll be believers only when the company starts offering support for third-party products, which was lacking in its RFP response.

For telecommuters, Avaya has one of the most complete and secure packages, which includes a client VPN and its SG200 Security Gateway. The telecommuter response also included an IP soft phone with speech control for dialing, directory access and conferencing. The SG200 Gateway provides a stateful firewall that could restrict access to the network based on the user's login ID. Although Avaya's unified messaging isn't quite as integrated as that of Siemens' product, it can provide control using spoken commands, which Siemens does not.

Avaya's presence application is provided through its IP Softphone R5 and comes with all the basics plus IM encryption. It isn't quite as extensive as the Siemens OpenScape product, however. For example, it doesn't integrate with groupware to update status via a groupware calendar the way Siemens' does, nor could HaveNoFear's users update their Outlook calendars using voice commands. Again, Avaya seems high on SIP, touting the SIP capabilities of its presence software, but the company wasn't ready to offer any tangible benefits, such as third-party phones or applications. The company did say that whenever HaveNoFear is ready, it could reduce costs and update its Avaya phones to SIP operation. Well, we've been ready to reduce costs and take advantage of SIP!

Communication Manager 2.0 Convergence Platform. Avaya, (866) GO-AVAYA.

Mitel's proposal totaled $150,400, which was the average price of all the systems. Mitel was above average, however, in its ability to provide a fully redundant 3300 ICP call controller. The redundancy in the call controller also extends to HaveNoFear's teleworkers. This helped Mitel in the PBX features category. We also liked the company's telecommuter proposal, which is similar to Avaya's. The 6010 teleworker box regulates access from telecommuter phones to the phone system and the rest of the network. It also terminates an encrypted audio stream to the phones used by the telecommuters.

Mitel's phones are capable of encryption, but none has VAD/silence-suppression capabilities. This is more of a problem if the phones are being used over a WAN, where bandwidth is dear. The phone does support G.711 and the more bandwidth-stingy G.729. Mitel's executive phones are unique in that they also can act as docking stations for Hewlett-Packard iPAQ model H5550 and H5555 PDAs. This makes it possible to activate phone features on the PDA's touchscreens and easily move those capabilities from one phone to another with the docking capabilities. Nice.

Mitel's unified-messaging proposal had all the integration we asked for, including letting users listen to, forward or delete e-mail messages from the phone. It lacks speech recognition that would allow hands-free operation but does support Exchange, Lotus Notes, GroupWise and IMAP4 e-mail systems.

Integrated Communications Platform (Release 4.1). Mitel Networks, (800) 648-3579, (613) 592-2122.

Interactive Intelligence Enterprise Interaction Center 2.3

Interactive Intelligence and Zultys were the only vendors to propose SIP-based systems, and Interactive Intelligence was the lone vendor to propose all third-party phones (understandable, since the company does not make its own phones). The price for the proposal came in at $156,084.

Interactive proposed all Polycom phones, with its Interaction Client to accompany executive models. The phones have lots of hard keys tied into major features as well as soft keys, volume and cursor movement keys, and full-duplex speaker phones.

VoIP Features Click to Enlarge

This is a pure SIP implementation, and Interactive's PBX features are all there--notable because it contradicted some vendors' claims that one of SIP's problems is its lack of features.

The company proposed a telecommuter setup that had all the basics tied to its Interactive Client system, which would act as a soft phone on home PCs. Interactive proposed a high-end conference server, which added $24,000 to its price but provides HaveNoFear with Web administration, including mail notifications for conferences. The unified-messaging system is fully integrated with voicemail and e-mail, and supports all major e-mail packages, including Exchange, Notes and GroupWise. The company did not include any IVR or speech-recognition capabilities, but did point out that these could be added via third-party products.

Enterprise Interaction Center 2.3. Interactive Intelligence, (317) 872-3000.

Alcatel delivered all the goods, including excellent unified messaging and presence support, but its high price ($171,132) hurt it in our scoring. A big reason for the high price was its phones: Basic models run $450 each and executive phones are $550. Here is a perfect example of how a mass-produced, third-party SIP phone could bring down the price. The irony is that more than a year ago, Alcatel announced support for SIP phones with great fanfare. Still, Alcatel made no mention of third-party support for SIP phones--or for any third-party SIP product, for that matter.

The phones have plenty of feature buttons as well as support for G.711, G.729 and G.723, with voice activity and silence suppression for G.729 and G.723. Alcatel used its executive phones for console operator phones, and we like that it specified Polycom's Soundstation for the conference phone. The PBX with the phones supports all 19 of the features in our VoIP checklist.

Alcatel's presence application, My Phone 4980, lets users dynamically route calls to their preferred locations based on the caller, time of day and calendar status. It also can monitor whether users are at their PCs based on the presence--or lack--of keystrokes. The presence application can be integrated with Lotus Notes, which can provide calendar-based updates to the system. Alcatel's unified messaging is tightly integrated with e-mail, and lets you delete and forward e-mail messages from the phone. It includes support for Exchange, Domino and IMAP4 but lacks IVR and speech recognition.

Alcatel OmniPCX Enterprise 5.1.2. Alcatel Internetworking Enterprise Solutions Division, (800) 995-261, (818) 878-4500.

Zultys Technologies MX250 Enterprise Media Exchange

Zultys, like Interactive Intelligence, provided a pure SIP proposal, but there were a number of differences in its approach. For example, Zultys delivered much of its functionality on an appliance, whereas the Interactive Intelligence product is software-based. Zultys makes its own SIP phones, which it proposed as part of the package, and made it clear that it also supports third-party SIP phones. The Zip 4x4 phones are full featured, with 25 buttons and 11 LEDs, and include three more switch ports than are usually included with a VoIP phone. Given Zultys' openness to third-party phones, we were surprised that it proposed a Zip 4x4 for conference phones and not a SIP version of Polycom's Soundpoint.

Zultys' PBX includes mirrored disk drives, but it lacks trunk-callback queuing and class-of-service capabilities. These let administrators restrict calling privileges on certain phones, which is especially useful for restricting long distance on public phones. We dinged Zultys in the ratings for that.

Zultys' telecommuting proposal, on the other hand, was as impressive as those from Avaya and Mitel. It proposed $392 Zip 4x5 phones, which provide a VPN that is terminated on the MX250. It also includes a firewall, support for Bluetooth wireless headsets and an analog port as a simple solution to maintaining accurate 911 information. The Zip 4x5 is a great example of the innovation that's possible when standards compel vendors to compete on functionality instead of vendor lock-in.

MX250 Enterprise Media Exchange. Zultys Technologies, (408) 328-0450.

Nortel's proposal was solid, and its unified-messaging capabilities are about the best in the industry. Unfortunately, its $248,500 price was $77,000 higher than the next most-expensive response. This really hurt Nortel in our ratings.

The company proposed a lot of hardware, much of which is also used in its higher-end systems. The phones are full-featured, and Nortel proposed the Polycom Soundstation for conference phones (the analog version). It did say that it plans to introduce a conference phone that supports SIP as well as its proprietary protocol. In fact, we discerned a trend: As with Avaya, Nortel claims to support SIP but did not propose any third-party SIP products, which could have helped it pricewise. The company did list the ipDialog Manitone SIP phone as being supported under its presence application. Nortel's presence application was impressive, with a long list of features that included the ability to exchange files, whiteboarding and point-to-point video calling. It does not work with groupware calendaring systems--an unfortunate lapse, as this is an obvious way to provide presence status.

Nortel's CallPilot unified-messaging offering is the best of the bunch. It works with all the major e-mail packages, and it has speech-recognition capabilities that make it possible to turn many telephone keypad functions into hands-free speech commands.

Succession 1000 3.0 and Multimedia Communication Server (MCS) 5100 2.0, $248,500. Nortel Networks, (800) 4NORTEL.

ShoreTel ShoreTel5 IP Phone System

ShoreTel (previously known as Shoreline) touts its ability to easily distribute all the functionality that comes with its call manager across multiple appliances via a single image. The company proposed two ShoreGear 120/24 voice switches for distributed call control, so if HaveNoFear loses one box, only that portion of the system is affected. With IP phone failover, the phones will link to a new box automatically. If it wanted more redundancy, HaveNoFear could add a third ShoreGear-120/24 for $5,000.

ShoreTel had all the standard PBX capabilities from our 19-item checklist, except group paging and trunk-callback queuing, which is employed when all outgoing trunks to the PSTN are in use. It will call back a phone that attempted to make a call during that time as soon as an outgoing trunk becomes available.

The company's phones are adequate, but ShoreTel and Mitel were the only vendors that didn't implement VAD/silence suppression. The company proposed its own IP210 phones as conference phones. However, these lack the omnidirectional design of most conference models. One notable feature that all its phones have is a Wideband codec. The ITU standard Wideband codec, known as G.722, provides a wider range of sound than conventional codecs, which could be helpful for conference calls. The downside is that G.722 requires a lot more bandwidth, though for LAN implementations that should not be an issue.

ShoreTel5 IP Phone System, $96,952. (800) 425-9385, (408) 331-3300.

Peter Morrissey is a full-time faculty member of Syracuse University's School of Information Studies, and a contributing editor and columnist for Network Computing. Write to him at [email protected].

Codecs convert analog signals to digital signals and back again. There are three common codecs used for voice: G.711, G.729 and G.723.

The standard codec is G.711, which uses Pulse Code Modulation to convert human speech to digits. PCM processes human speech at a rate of 8,000 samples per second, putting 8 bits of data within a sample--that's about 64,000 bits of data in one second. The digital backbone of the PSTN is built around this increment, and when you run it over Ethernet, utilization comes to around 80,000 bits per second after all the protocol overhead is factored in.

The G.729 codec uses compression to decrease bandwidth utilization to roughly half of G.711 on an Ethernet network. The disadvantage of G.729 is that the compression process adds delay, which, if it gets too high, will impact the quality of the call.

G.723 provides further compression with even greater delay.

RFP Scenario

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The company's phones are adequate, but ShoreTel and Mitel were the only vendors that didn't implement VAD/silence suppression. The company proposed its own IP210 phones as conference phones. However, these lack the omnidirectional design of most conference models. One notable feature that all its phones have is a Wideband codec. The ITU standard Wideband codec, known as G.722, provides a wider range of sound than conventional codecs, which could be helpful for conference calls. The downside is that G.722 requires a lot more bandwidth, though for LAN implementations that should not be an issue.

ShoreTel5 IP Phone System, $96,952. (800) 425-9385, (408) 331-3300.

Presence makes it possible to monitor someone's current availability status via all of his or her communication mediums--similar to an IM Buddy List but more accurate and more flexible. Presence applications usually have some type of GUI that will list all of the individuals within an organization with whom you communicate, along with icons and text messages that indicate their current status--you can even see if they have typed anything on their keyboard within a predefined amount of time.

Presence can make communications much more productive because users will know immediately the best way to contact coworkers. For example, say a good customer calls for a sales rep. The receptionist knows the rep is in her office and transfers the customer call. However, the rep is on her phone, so the customer gets dumped into voicemail. With presence, the person who answered the call would be able to avoid this situation and might use IM to alert the rep to the call. If your VoIP system is integrated with a groupware platform, it can even show if a person is in a meeting.

Users can set up rules for contacting them, and in some cases these rules can be different for different callers. For example, they can set a rule that says if the boss calls, ring the office phone and the cell phone at the same time, but if a salesperson calls, send the call directly to voice mail.

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