The present invention relates generally to line cards for interfacing two telecommunication systems and more particularly, to a line card for supporting circuit switching and packet switching and for supporting high speed multimedia applications. 
Electronic communication systems are quickly becoming essential to today""s society.  Current communication systems utilize a number of high speed communication formats.  Packet based formats are becoming more and more popular.  Both synchronous and asynchronous communications formats have been used in a variety of different applications.  These communication formats include asynchronous transfer mode (ATM), ethernet and frame relay.  Each of these formats have different protocols and, in current communication systems, require different transmission systems.  Additionally, a significant portion of communications continue to be provided over plain old telephone services (POTS) or circuit based switching systems. 
Complicating matters even more, different communication formats are used to support different multimedia applications.  Multimedia applications may include voice communications, video communications and data communications.  These high speed applications similarly require a number of dedicated transmission devices. 
One of the electronic devices which are important to these communication systems are line cards.  Line cards provide the interface between a transmission line or bus and other electronic devices, such as digital signal processors.  Currently, line cards are also designed and manufactured to support specific types of communication formats and applications.  Thus, service providers are unfortunately required to have dedicated line cards for specific applications.  If service providers desire to add additional, higher speed services, they must acquire new line cards. 
Accordingly, there is a need in the art for a line card for supporting circuit switching and packet switching applications and for supporting multimedia applications. 
In accordance with an aspect of a present invention, a line card is provided with supports both circuit switching and packet data switching.  The line card may comprise a multimedia circuit for supporting multimedia applications.  The multimedia applications may comprise anyone or more of video, voice and data. 
An interface circuit provides an interface between high speed applications, such as any of asynchronous transfer mode, ethernet and frame relay.  The line card may comprise a conversion circuit for performing synchronous to asynchronous traffic conversion.  The conversion circuit may be a synchronous to asynchronous converter-time slot interchange. 
In accordance with another aspect of the present invention, a line card comprising a multimedia circuit for supporting multimedia applications; and a conversion circuit for converting synchronous traffic to asynchronous traffic is provided. 
These and other features and advantages of the present invention will become apparent from the following detailed description, the accompanying drawing and the appended claims.