Metro Area Networking
Detailing the technological challenges and opportunities in a lucid, humorous prose, this book lays bare the tricks and traps awaiting service providers in the metro area space.
TABLE OF CONTENTS Metro Area Networking
The Arrival of Fast Ethernet
In 1995, the IEEE announced the 100 Mbps 802.3u 100BaseT standard. Commonly known as Fast Ethernet, the standard actually comprises three disparate substandards, which in turn support three different transport media. These include 100BaseTX, which operates over two pairs of CAT 5 twisted pair; 100BaseT4, which operates over four pairs of CAT 3 twisted pair; and 100BaseFX, which operates over a pair of multimode optical fibers. It was deemed necessary to offer a version for each of these media types because of the evolving customer environment; more on this will be covered later.
Two-Way Ethernet
Due to popular demand as they say, the IEEE announced 802.3x in 1997, which provided a standard that governed full-duplex Ethernet. By allowing stations on an Ethernet LAN to simultaneously transmit and receive data, the need for a medium contention mechanism such as CSMA/CD was eliminated, allowing two stations to transmit simultaneously over a shared point-to-point facility. The standard was written to accommodate all versions of Ethernet, including Fast Ethernet.
The IEEE also released the 802.3y 100BaseT2 standard in 1997, which provided a mechanism for transmitting at 100 Mbps over two pairs of CAT 3 balanced wire.
The Arrival of Gigabit Ethernet
In 1998, Gigabit Ethernet arrived on the commercial scene. Like Fast Ethernet, the 802.3z 1000BaseX standard supported three different transmission mechanisms with three substandards: 1000BaseSX relied on an 850 nm laser over multimode fiber, 1000BaseLX used a 1300 nm laser over both single and...
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