1. Technical Field
The present invention relates in general to the transmission of data between local area networks (LANs) and in particular to a system for transmitting data between LANs through an asynchronous transfer mode (ATM) crossbar switch.
2. Description of the Related Art
Today, asynchronous transfer mode (ATM) technology is improving at a rapid rate. Most research developments in this field are concentrated in high-speed ATM networks instead of LANs. Extremely high speed ATM switches are now readily available and are utilized for transferring data between LANs coupled to the ATM switch. The utilization of the ATM technology for switching LAN frames requires a transformation of each LAN frame by splitting the LAN frame into ATM frames. This is accomplished by encapsulating each LAN frame in the ATM adaptation layer (AAL) format.
The LAN frame is transformed into ATM data packets in the AAL format via a special module. The LAN frame is then transferred to the switch card for switching. Such a requirement results in two major drawbacks. Since the frame is converted into ATM cells, a header in each cell including protocol information (e.g., destination address) is required. A second drawback is that the transformation of the LAN frame into ATM cells and the encapsulation in the AAL format requires important and costly hardware and software.
Consequently, it would be desirable for a system and method of exchanging data between multiple LANs without the protocol information header and the utilization of costly hardware and software.