e receiver do signal conversions need to be done. Multiplexing Multiplexers, often called muxes, are extremely important to telecommunications. Their main reason for being is to reduce network costs by minimizing the number of communications links needed between two points. Like all other computing systems, multiplexers have evolved. Each new generation has additional intelli- gence, and additional intelligence brings more benefits. The types of benefits that have accrued, for example, include the following: The capability to compress data in order to encode certain characters with fewer bits than normally required and free up additional capacity for the movement of other information. The capability to detect and correct errors between the two points being connected to ensure that data integrity and accuracy are maintained. The capability to manage transmission resources on a dynamic basis, with such things as priority levels. If you have only one 64Kbps channel left, who gets it? Or what happens when the link between San Francisco and Hong Kong goes down? How else can you reroute traffic to get the high- priority information where it needs to go? Multiplexers help solve such problems. The more intelligent the multiplexer, the more actively and intelligently it can work to dynamically make use of the available transmission resources. When you're working with network design and telecommunications, you need to consider line cost versus device cost. You can provide extremely high levels of service by ensuring that everybody always has a live and available communications link. But you must pay for those services on an ongoing basis, and their costs become extremely high. You can offset the costs associated with providing large numbers of lines by instead using devices such as multiplexers that help make more intelligent use of a smaller number of lines. Figure 1.12 illustrates a network that has no multiplexers. Let's say this net- work is for Bob's department stores. The CPU is at Location A, a data center that's in