LAN segmentation
4.2.1 This page will explain LAN segmentation.
A network can be divided into smaller units called segments. Figure
shows an example of a segmented Ethernet
network. The entire network has fifteen computers. Of the fifteen computers,
six are servers and nine are workstations. Each segment uses the CSMA/CD access
method and maintains traffic between users on the segment. Each segment is its
own collision domain. 
Segmentation allows network congestion to be significantly reduced within each segment. When data is transmitted within a segment, the devices within that segment share the total available bandwidth. Data that is passed between segments is transmitted over the backbone of the network through a bridge, router, or switch.
The next page will discuss bridges
LAN segmentation wit
4.2.2 This page will describe the main functions of a bridge in a LAN.
Bridges are Layer 2 devices that forward data frames based on the
MAC address. Bridges read the source MAC address of the data packets to
discover the devices that are on each segment. The MAC addresses are then used
to build a bridging table. This allows bridges to block packets that do not
need to be forwarded from the local segment. Although bridges are transparent to other network devices, the latency on a network increases by ten to thirty percent when a bridge is used. The increased latency is because of the decisions that bridges make before the packets are forwarded. A bridge is considered a store-and-forward device. Bridges examine the destination address field and calculate the cyclic redundancy check (CRC) in the Frame Check Sequence field before the frame is forwarded. If the destination port is busy, bridges temporarily store the frame until that port is available.
The next page will discuss routers.h bridges
No comments:
Post a Comment