
Installation Prerequisites
Microcode Overview
The FEIP microcode (firmware) is an image that provides
The show controllers cbus command displays the currently loaded and running microcode version for each interface processor, and FEIP. The show
Software and interface processor microcode images are carefully optimized and bundled to work together. Overriding the bundle can result in system incompatibilities. We recommend that you use the microcode included in the software bundle. For a complete description of microcode and downloading procedures, refer to the section “Upgrading FEIP Microcode” on page 37.
Fast Ethernet Overview
The term Ethernet is commonly used for all carrier sense multiple access/collision detection (CSMA/CD),
Note
Environment B.
IEEE 802.3u is well suited to applications where a local communication medium must carry sporadic, occasionally heavy traffic at high peak data rates. Stations on a CSMA/CD LAN can access the network at any time. Before sending data, the station listens to the network to see if it is already in use. If it is, the station waits until the network is not in use, then transmits; this is
A collision occurs when two stations listen for network traffic, hear none, and transmit very close to simultaneously. When this happens, both transmissions are damaged, and the stations must retransmit. The stations detect the collision and use backoff algorithms to determine when they should retransmit. Both Ethernet and IEEE 802.3u are broadcast networks, which means that all stations see all transmissions. Each station must examine received frames to determine if it is the intended destination and, if it is, to pass the frame to a higher protocol layer for processing.
IEEE 802.3u specifies the following different physical layers for
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8Fast Ethernet Interface Processor (FEIP) Installation and Configuration