In contrast to packet-switched technologies, asynchronous transmission guarantees timely delivery of information, avoiding delay and jitter. The premise behind asynchronous Ethernet is that voice (not audio or video) is the critical component in multimedia communications.¹ Hence, this technology is most important at locations where videoconferencing is the primary multimedia application.

To ensure that voice receives priority, a special asynchronous ISDN 6.144M-bps line is added to the standard Ethernet technology. This additional bandwidth is sufficient for a multipoint videoconference with six participants, each using 384K bps and additional bandwidth for such ancillary functions as white boarding. In addition, asynchronous Ethernet is easy to add to existing Ethernet networks, because all that is required is an asynchronous Ethernet hub and cards for the computers involved in videoconferencing. On segments where such asynchronous capability is not required, it need not be added.²

Suitability for Multimedia Traffic. Asynchronous Ethernet is a shared-media approach with limited multicasting support for audio only. It is not suited for full-motion video (i.e., the Moving Picture Experts Group or Motion Picture Experts Group standard), but it supports H.261 video (the teleconferencing standard). It provides truly asynchronous support for voice.³ From a business perspective, asynchronous Ethernet is only suitable as a small workgroup solution and where multimedia needs are not great. The technology should be viewed as a transitionary step to ATM technology.