The networked phone
VOIP takes off as agencies look to exploit broadband data networks
- By David Essex
- Jan 07, 2005
Voice over IP almost didn't survive its over-hyped debut in the last decade. It often disappointed, with kludgy hardware, quirky software, and dropped packets that ruined many calls.
Now VOIP'phone calls transmitted over private networks and the Internet rather than traditional phone systems'has a second life. New quality-of-service standards and more powerful analog-to-digital coders/decoders have brought sound quality and signal reliability within shouting range of the traditional public switched telephone network (PSTN).
But the promised revolution has been slow in coming. 'Voice over IP has been a little slow to take off in the government,' said Shawn McCarthy, senior analyst at International Data Corp. and the Internaut columnist for GCN. 'Penetration is under 15 percent.'
Still, news of recent government pilots and installations is abundant. Net2Phone Inc., a VOIP service provider that also sells hardware, has partnered with cable company Rural West to outfit military housing with special adapters to dial traditional analog calls over the cheaper broadband Internet. The Air Force in recent years has been replacing its digital phone systems with Nortel Networks VOIP switches. A ShoreTel network links a Utah desert test site with NASA research centers, and the Navy used ShoreTel equipment to set up phones for mobile medical units. The Texas Health and Human Services Commission built a statewide 211 community information system on call center and VOIP technology from Cisco Systems.
VOIP can still save money on phone bills, but increasingly it's seen as a way to bring sophisticated call control and messaging to more workers and locations.
'It's not just about quality,' said David Span, Net2Phone's senior vice president for product management and marketing. 'You can get features that you couldn't get on a traditional PSTN,' Span said, and make call waiting, three-way calling, caller ID, and voice mail the standard rather than the exception.
On more and more networks, government agencies and corporations are pairing VOIP with multimedia communications'typically adding videoconferencing'as well as channels such as instant messaging and PC whiteboarding in a broader mix called IP telephony.
New Power over Ethernet technology ensures that VOIP lines, which normally aren't powered like traditional copper phone lines, stay up in a power failure. 'The benefit of in-line power is you can have a UPS [uninterruptible power supply] in a closet that keeps power to the phones,' said Steve Childs, a product manager in Cisco's government systems unit.
Security, too, is becoming a focus as the military brings VOIP to the Iraqi desert and other hostile environments. The Defense Department's Joint Operability Test Command has begun issuing PBX2 certifications to products with strict enough interoperability, reliability, and security for use with DOD installations.
There are essentially five main categories of VOIP infrastructure:
- Gateways, consisting of software'typically embedded in stackable appliances, but often in other devices'that translate between IP and the PSTN
- Standard network hardware, such as routers and switches, equipped with gateways and other telephony features
- Servers, either stackable or in standard PC form factors, that handle call management and run telephony applications
- Endpoints, typically IP phones and consoles
- Adapters that connect analog phones to the network.
The accompanying chart (on Page 34) excludes the adapters and such special-purpose products as gateways for specific legacy voice mail systems and customer-premises hardware sold to telecom carriers. In a break with the usual convention, I have shown product series names, not specific model names, whenever the latter were too numerous or their differences too minor to note.