- Telephony modems convert the analog signals of telephone lines--which are continuously variable--into the digital signals needed for DSL Internet networks, which operate on stable signals. This Internet protocol conversion is usually used for voice communication in residential environments. As of November 2010, global communications company ARRIS manufactures three different telephony modem models with varying specifications.
Touchstone Telephony Modem TM502G
- ARRIS' Touchstone Telephony Modem TM502G, successor to the ARRIS Touchstone TM402 model, stands as the company's mid-range telephony modem offering. This modem features two lines of primary line voice over Internet protocol, or VoIP, alongside high-speed data access. A lithium-ion battery powers the TM502G, supporting the modem even during power outages. A PacketACE configuration file editor offers interoperability with other communication devices, while software configuration allows for customizable battery management and operation parameters. The TM502G measures 8.6 inches high, 2.1 inches wide and 7.1 inches deep and weighs 1.2 pounds.
Touchstone Telephony Modem TM502A
- The specifications of the ARRIS Touchstone Telephony Modem TM502A are similar to the TM502G model, though this unit is a simplified, basic model. Like the TM502G, the TM502A features two lines of VoIP with high-speed data access. Also like the TM502G, this model uses Boost Current technology and automatic gain compensation to increase its compatibility with existing communication technology in the home, such as cable modems and routers. The TM502A updates via remote software upgrades. This unit's exterior specifications are slimmer than the TM502G. It is 7.3 inches high, 1.9 inches wide and 7.1 inches deep. It weighs 1.06 pounds.
Touchstone Telephony Modem TM702G
- Of all the ARRIS telephony modem line, the ARRIS Touchstone Telephony Modem TM702G offers the most feature-heavy list of specifications. This Embedded Media Terminal Adaptor--or E-MTA--device features two primary line carrier-grade VoIPs, ultra-high speed data access and two battery pack configurations capable of powering the unit during outages. Via DOCSIS 3.0 channel bonding, this modem transfers data at speeds over 160 megabytes per second. With channel-bonding, the modem combines the network interfaces of two or more host computers. The unit supports PacketACE configuration file editing and multiple protocols, including PacketCable for streamlined data transmission and session initiation signaling protocols, which help establish voice, video and gaming connections. Physically, the TM702G is ARRIS' heftiest model, measuring 8.6 inches high, 2.1 inches wide and 7.1 inches deep and weighing 1.5 pounds.