The SVP server is an odd box that doesn’t conform to any common IT hardware standard -- it won’t fit nicely in a rack, for instance. It runs embedded Linux, and it has only a single tip-and-ring power connection and a single network connection. When a handset boots and contacts the SVP server, the SVP server then connects to the SIP server using another dedicated IP address. This means that each handset requires two IP addresses: one for the handset itself and another for the proxy connection to the PBX. From the PBX point of view, the extension is on an IP assigned to the SVP server, not the handset. This allows the SVP server to handle a variety of QoS tasks. Working with compatible access points, it pushes VoIP traffic to and from the handset to the top of the queue, ensuring that the latency-sensitive packets are delivered in a timely fashion. This results in better call quality and assists in AP roaming functions. The mechanism is a bit ungainly, but it serves a useful purpose. Further, multiple SVP servers can be configured in a redundant fashion.

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Call quality on the e340 is good, assuming that the unit is reasonably close to an access point. Drifting further from the AP can result in transmitted voice taking on a “Donald Duck” tone while received audio is still clear and crisp. I also noted that the handsets will hang onto a distant AP longer than they should when another AP is closer. And the e340s are quirky to use. The soft buttons are not only very small, but require significant pressure to trigger. That said, my inclement weather test (basically, leaving a handset out in the rain overnight) resulted in some misting of the LCD screen, but no other ill effects. This certainly isn’t a recommended use of the phones, but it’s nice to know that a little water won’t necessarily kill a handset outright.

Battery life is good. I conducted conversations lasting several hours with these phones without any problems. Also, they don’t get nearly as hot during normal operation as some other Wi-Fi VoIP handsets, which is a definite plus. A hot phone is not conducive to normal conversation. The e340 does have a standard minijack at the bottom for a headset, though I did note some quality loss when using a Plantronics headset. And try as I might, I couldn’t get the message waiting indicator to trigger on the e340. It’s represented as an icon on the LCD screen, but it doesn’t seem to work with Asterisk.

I’ve tested and used a variety of Wi-Fi VoIP handsets, and the SpectraLink NetLink e340 is right up there in terms of overall quality, ruggedness, and performance. I found a few minor annoyances and quirks, such as the difficult buttons and odd SVP server footprint and dual-IP scheme, but overall it’s a worthy product.

There’s still plenty of room to grow in this space, and as of yet, I haven’t found the truly perfect VoIP phone. Given that VoIP rollouts require a variety of phone types to meet needs throughout the enterprise, standardizing on a single phone vendor is really the only way to go. It means less hassle, easier configuration, and smoother implementation. Collectively, these units show that Polycom is serious about VoIP and SIP telephony. The Polycom line has a little something for everyone, including lower-end handsets that I didn’t test for this article. Especially in an Asterisk environment, Polycom phones are clear winners.