Historically, cable operators provided only video programming over their cable systems. To provide this video programming, equipment at the head-end (central locations) transmitted the television programming, much like legacy television programming does over the air, over coaxial cable to the subscribing homes. These initial systems were designed for one purpose, namely, one-way transmission of video from the head-end to the homes. Splitters and amplifiers were utilized to split/send the signals to the many homes. These splitters and amplifiers basically enabled one-way communications (to the homes). Over time, this programming was upgraded to include programming that was available at an extra charge. Initially, this was accomplished by putting RF blocks outside of each home to block the stations that a user did not subscribe to. This provided video.

Over the last 3-5 years, cable modems have been introduced to provide data access over the cable systems. These cable modems provide home-based Internet access to users through the cable plant as an alternative to dial-up Internet access and Digital Subscriber Line (DSL) Internet access. The addition of this data capability was not as easy of a task. Internet access requires two-way communications and many of the networks deployed only allowed one-way communications (to the homes). Cable operators have been upgrading their older networks to allow for data communications and have been using equipment which allows two-way communications through the network. An added benefit of the two-way communications is the ability to also use set top boxes to provide "Pay Per View" video programming, whereby users can pay for an individual movie when they want to watch it. It also allows the operators to better manage subscription services for each user (e.g., which program packages each user has signed up for). These changes allowed for Video and Data.

This brings us to today. Voice over IP (VoIP) is being deployed in long distance networks, enterprise networks, and even local access networks. VoIP services like Vonage and AT&T's CallVantage are able to provide VoIP services over the broadband Internet access provided by the cable operators. Cable operators are beginning to also offer VoIP over their cable networks as an additional service to their subscribers. This is essentially the Triple Play that many in the industry are talking about — namely, Voice, Video & Data. This allows cable operators to compete for local phone service with the incumbent phone providers by bundling the voice, video and data services into a common package under a single bill, which is attractive to many users.

To provide this service, similar to other VoIP networks, VoIP media gateways are required at the head-end to terminate the voice packets received over the IP network and to complete the call to the remote party. Users have a small analog media gateway in their homes to provide access by standard phones and fax machines. Some cable operators are also deploying local and/or long distance networks to also handle the long distance portion of the calls for additional revenue. In the future, cable operators may work with cellular operators to offer a quadruple play where cellular service is added, but that is a subject for another newsletter.

AudioCodes' media gateways have been designed to operate within cable networks and are being deployed today into cable networks globally. These media gateways take advantage of AudioCodes' legacy of providing high quality Voice over IP solutions. Additionally, the media gateways are qualified by CableLabs, a cable industry organization whose purpose is to specify and qualify the various components of a cable network.