Overview

Interconnection, data transfer modes, networking protocols, and the like continue to be hot topics in today's ever expanding digital media technologies. The technical methodology associated with moving data around in a system begins at the transport level (sometimes called transport layer). Even though it is the physical layer that makes the actual contact with the media (the wire or optical fiber), it is further up the network model, at OSI Layer 4-Transport, that all the details get put together.

Standards aimed at making the interoperability of data communications possible are constantly evolving. The establishment of the MPEG compression standards, the transport protocols such as SDTI, and the multiplexing of the packetized elementary streams, are critical elements in the system. Part of the standards process includes making certain that data can be efficiently and effectively exchanged, stored, and forwarded on a variety of cabling, networking, and transmission topologies.

The most prevalent of network media is Ethernet. The name is nothing new to most of us. What it does and how it works still raises eyebrows even in broadcasting technical circles. In the past couple of years, those getting into multimedia and digital video on the computer desktop arena have dealt with Ethernet as the method of choice. We venture to bet, though, Ethernet is still one of the more confused of the various network topologies and connection interfaces.

As voice, data, and media technologies grow ever closer together, some difficult and expensive decisions will need to be made in the network...