A front-end processor (FEP) is a type of computer used in a network to help the main host computer manage the other connected computers. The primary reason for using a front-end processor is to keep the main computer from having to perform all the processing, which requires a lot of computer resources. Depending on the number of nodes to which the FEP can connect, the FEP may have relatively common hardware or very strong hardware. To help administrators with security, these computers often can eavesdrop on data transmissions.
The purpose of a front-end processor is fairly simple. In a network, there is a lot of data transmissions going from the host to the nodes, back to the host and out to other places. The host computer normally handles these transmissions. When an FEP is used, it takes over the process of managing these transmissions and reports directly to the host.
While a host computer can perform these tasks without a front-end processor, there are many advantages to use an FEP. In networks in which there are hundreds or thousands of nodes, this can be a difficult task for any single computer. The computer's need to use resources to manage the nodes means the host computer must be very powerful if it is not to provide poor performance on other tasks. For example, if the host user wants to run a program without using an FEP or having a strong system, then the computer may take a long time to load and run the program.
A front-end processor typically is outfitted with powerful hardware, but this depends on the size of the network. If the network is a relatively small size, such as less than 100 computers and devices, then the FEP typically does not need to be very powerful and may have hardware similar to other computers. When the network is large, the FEP typically will need much stronger hardware to ensure it can handle the management task without involving the host computer or crashing from the stress.
Another reason for using a front-end processor is that it enables the host user to eavesdrop on data transmissions. This type of eavesdropping is ethical and sound, because the host user typically is just looking for data that may compromise the network’s security, business trade secrets or other information that network users are not supposed to transfer. All the data go through the FEP, so it is uniquely suited for this task.