Perhaps you regarded IP telephony with cautious optimism when you first heard of it.

You know that converting calls to packet data can save you a lot of money on long-distance charges, but you've already spent enough money to purchase your PBX. That's why the latest generation of IP products can either replace your PBX or can work with your existing PBX to enable you to send voice-over-IP calls directly to agents' phones.

When you send and receive calls as data, or as packet-switched calls, you don't have to pay the cost of toll calls to transmit the data through your phone lines. A circuit-switched phone call requires you to pay a distance charge for each call, but a packet-switched call does not incur these charges. If you purchase a hybrid IP gateway and PBX, you can also route the voice-over-IP calls to special types of phones, known as IP phones, which you can connect directly to your local area network.

When you connect an IP gateway to a PBX, the gateway converts the call, which is a circuit-switched call, into packets of data. Gateways contain software that compresses the data so that your center can carry multiple packet-switched calls on one phone line. At the other end of a call, an IP gateway decompresses the packets of data and converts the data to audio signals. The IP gateway at the other end of the call is also connected to a PBX, and the call ultimately leaves the PBX as a circuit-switched call.

You can also use IP gateways without a phone switch to enable agents to receive customers' calls over a data network. If you're building a new center, you can consider IP telephony systems to save money on long-distance costs and on building separate phone and computer networks. Bear in mind that any delay in receiving packets can affect the audio quality of a voice-over-IP call.

With a growing number of options for you to choose from, here's a look at IP telephony products that you can use with or without your PBX.

A Look at IP Gateway Products That Work With Phone Switches
Some companies that sell phone switches now also offer IP cards that enable the switch to send and receive packet-switched calls. Nortel Networks (Richardson, TX) manufactures IP cards for its Meridian 1 phone switch, and you can use them to route voice-over-IP calls between call centers at different locations. You plug the Meridian Integrated IP Telephony Gateway 2.0 (ITG) card into your Meridian 1 at one site to convert circuit-switched calls into packet data, and you connect the switch to a router on your Ethernet. The router delivers calls through a wide area network to a router at another site; the router at the other site is also connected to a Meridian 1 switch. The ITG card inside that switch then converts the packet-switched call into a circuit-switched call.

The Meridian Integrated IP Telephony Gateway 2.0 card supports 24 trunks. If you manage a smaller multi- site network, the Meridian Integrated Telephony Gateway 1.0 accommodates eight trunks. You can also plug more than one card into the same Meridian 1 switch if you need additional ports. The ITG 2.0 gateway costs $6,590 and the ITG 1.0 costs $3,290. Nortel Networks also offers its Meridian Line ITG 2.0 card, which you connect to agents' PCs or to IP phones. The line card can handle up to 24 simultaneous conversations and costs $6,200.

Nortel Networks isn't the only company to offer voice-over-IP cards for its PBX products. Lucent Technologies (Murray Hill, NJ) introduced a new IP card and software for its Definity phone switch in July. The IP Media Processor works with Definity Release 8.3, the latest upgrade to the switch's software.

You plug the IP Media Processor into a single slot in the Definity switch, and you connect the switch to agents' phones through a local area network or wide area network. The IP Media Processor has its own software for compressing and decompressing data. The software is embedded on a chip on the card itself.

Lucent still also offers its Definity IP Trunk Card, which works with Definity Release 8.2. You connect the Definity IP Trunk Card to three slots in the Definity switch. It also includes its own hard drive that converts phone calls to voice-over-IP calls and vice versa.

Another key difference between the Definity Trunk IP Card and the IP Media Processor is how often each of them collects packets. The Definity Trunk IP Card receives packets every 30 milliseconds, but the IP Media Processor can vary its rate of collecting packets between 10 to 30 milliseconds. Release 8.2 and Release 8.3 both gauge how much bandwidth you're currently using and enable IP Media Processor to determine the amount of bandwidth each voice-over-IP call requires. Agents experience no significant delays when receiving each voice-over-IP call, and the steady flow of data to agents' phones, IP phones or PCs helps to ensure good audio quality.

Agents who use either Release 8.2 or Release 8.3 software receive customers' information at their PCs, like their names and phone numbers, and can forward or transfer voice-over-IP calls to anyone connected to your call center's network. If you want to send calls to agents' PCs, both cards also work with Lucent's Definity IP Softphone, which is software that you install on PCs running Windows 95, Windows 98 or Windows NT. Soft phones, the generic term for this type of software, enables agents to view customers' information and to hold, transfer or conference voice-over-IP calls by clicking on icons from their PCs.

The IP Media Processor and Definity IP Trunk Card each costs $12,720. Lucent sells a modem, Windows NT server software and Symantec's pcAnywhere32 software with the IP Trunk Card, raising the card's total price to $14,000. Definity Release 8.3 costs $23,500 for 30 agents, including 30 licenses for the Definity IP Softphone software, 12 voice-over-IP ports and 24 T-1 ports. To upgrade from Definity Release 8.2 to Release 8.3, you pay $100.

NEC America (Irving, TX), a subsidiary of NEC that manufactures telecommunications hardware, plans to release IP trunk cards and IP line cards for its Neax PBX series before the end of the year. The company has already set pricing for most of its trunk cards, but pricing for the line cards was not available at press time. An eight-port trunk card for the Neax2400 IMX phone switch costs $6,600 and a 16-port trunk card costs $10,000. A trunk card with four ports for the Neax2000 IVS or Neax1000 IVS/VSP costs $3,700, and a card with eight ports costs $5,100.

Each Neax PBX has a different number of ports to accommodate phones or IP phones. The Neax1000 has 48 ports, and you can purchase four versions of the Neax2000 IVS with 48, 72, 320 or 512 ports. You can scale the Neax2400 IMX to up to 60,000 ports. NEC America also offers Neax Express, a PBX that runs on a Windows NT server instead of with a proprietary operating system. Neax Express scales up to 128 ports and enables you to install additional software on the same server, such as a database containing customer information. The company will introduce a trunk card and a line card for Neax Express this year.

Perhaps you regarded IP telephony with cautious optimism when you first heard of it.

You know that converting calls to packet data can save you a lot of money on long-distance charges, but you've already spent enough money to purchase your PBX. That's why the latest generation of IP products can either replace your PBX or can work with your existing PBX to enable you to send voice-over-IP calls directly to agents' phones.

When you send and receive calls as data, or as packet-switched calls, you don't have to pay the cost of toll calls to transmit the data through your phone lines. A circuit-switched phone call requires you to pay a distance charge for each call, but a packet-switched call does not incur these charges. If you purchase a hybrid IP gateway and PBX, you can also route the voice-over-IP calls to special types of phones, known as IP phones, which you can connect directly to your local area network.

When you connect an IP gateway to a PBX, the gateway converts the call, which is a circuit-switched call, into packets of data. Gateways contain software that compresses the data so that your center can carry multiple packet-switched calls on one phone line. At the other end of a call, an IP gateway decompresses the packets of data and converts the data to audio signals. The IP gateway at the other end of the call is also connected to a PBX, and the call ultimately leaves the PBX as a circuit-switched call.

You can also use IP gateways without a phone switch to enable agents to receive customers' calls over a data network. If you're building a new center, you can consider IP telephony systems to save money on long-distance costs and on building separate phone and computer networks. Bear in mind that any delay in receiving packets can affect the audio quality of a voice-over-IP call.

With a growing number of options for you to choose from, here's a look at IP telephony products that you can use with or without your PBX.

A Look at IP Gateway Products That Work With Phone Switches
Some companies that sell phone switches now also offer IP cards that enable the switch to send and receive packet-switched calls. Nortel Networks (Richardson, TX) manufactures IP cards for its Meridian 1 phone switch, and you can use them to route voice-over-IP calls between call centers at different locations. You plug the Meridian Integrated IP Telephony Gateway 2.0 (ITG) card into your Meridian 1 at one site to convert circuit-switched calls into packet data, and you connect the switch to a router on your Ethernet. The router delivers calls through a wide area network to a router at another site; the router at the other site is also connected to a Meridian 1 switch. The ITG card inside that switch then converts the packet-switched call into a circuit-switched call.

The Meridian Integrated IP Telephony Gateway 2.0 card supports 24 trunks. If you manage a smaller multi- site network, the Meridian Integrated Telephony Gateway 1.0 accommodates eight trunks. You can also plug more than one card into the same Meridian 1 switch if you need additional ports. The ITG 2.0 gateway costs $6,590 and the ITG 1.0 costs $3,290. Nortel Networks also offers its Meridian Line ITG 2.0 card, which you connect to agents' PCs or to IP phones. The line card can handle up to 24 simultaneous conversations and costs $6,200.

Nortel Networks isn't the only company to offer voice-over-IP cards for its PBX products. Lucent Technologies (Murray Hill, NJ) introduced a new IP card and software for its Definity phone switch in July. The IP Media Processor works with Definity Release 8.3, the latest upgrade to the switch's software.

You plug the IP Media Processor into a single slot in the Definity switch, and you connect the switch to agents' phones through a local area network or wide area network. The IP Media Processor has its own software for compressing and decompressing data. The software is embedded on a chip on the card itself.

Lucent still also offers its Definity IP Trunk Card, which works with Definity Release 8.2. You connect the Definity IP Trunk Card to three slots in the Definity switch. It also includes its own hard drive that converts phone calls to voice-over-IP calls and vice versa.

Another key difference between the Definity Trunk IP Card and the IP Media Processor is how often each of them collects packets. The Definity Trunk IP Card receives packets every 30 milliseconds, but the IP Media Processor can vary its rate of collecting packets between 10 to 30 milliseconds. Release 8.2 and Release 8.3 both gauge how much bandwidth you're currently using and enable IP Media Processor to determine the amount of bandwidth each voice-over-IP call requires. Agents experience no significant delays when receiving each voice-over-IP call, and the steady flow of data to agents' phones, IP phones or PCs helps to ensure good audio quality.

Agents who use either Release 8.2 or Release 8.3 software receive customers' information at their PCs, like their names and phone numbers, and can forward or transfer voice-over-IP calls to anyone connected to your call center's network. If you want to send calls to agents' PCs, both cards also work with Lucent's Definity IP Softphone, which is software that you install on PCs running Windows 95, Windows 98 or Windows NT. Soft phones, the generic term for this type of software, enables agents to view customers' information and to hold, transfer or conference voice-over-IP calls by clicking on icons from their PCs.

The IP Media Processor and Definity IP Trunk Card each costs $12,720. Lucent sells a modem, Windows NT server software and Symantec's pcAnywhere32 software with the IP Trunk Card, raising the card's total price to $14,000. Definity Release 8.3 costs $23,500 for 30 agents, including 30 licenses for the Definity IP Softphone software, 12 voice-over-IP ports and 24 T-1 ports. To upgrade from Definity Release 8.2 to Release 8.3, you pay $100.

NEC America (Irving, TX), a subsidiary of NEC that manufactures telecommunications hardware, plans to release IP trunk cards and IP line cards for its Neax PBX series before the end of the year. The company has already set pricing for most of its trunk cards, but pricing for the line cards was not available at press time. An eight-port trunk card for the Neax2400 IMX phone switch costs $6,600 and a 16-port trunk card costs $10,000. A trunk card with four ports for the Neax2000 IVS or Neax1000 IVS/VSP costs $3,700, and a card with eight ports costs $5,100.

Each Neax PBX has a different number of ports to accommodate phones or IP phones. The Neax1000 has 48 ports, and you can purchase four versions of the Neax2000 IVS with 48, 72, 320 or 512 ports. You can scale the Neax2400 IMX to up to 60,000 ports. NEC America also offers Neax Express, a PBX that runs on a Windows NT server instead of with a proprietary operating system. Neax Express scales up to 128 ports and enables you to install additional software on the same server, such as a database containing customer information. The company will introduce a trunk card and a line card for Neax Express this year.