will have at least enough storage allocated to handle the data being written or read at the port. A port name can be used instead of an address to refer to a port. A name is normally easier to remember than an address. Operating systems sometimes have predefine names associated with certain ports. For example, DOS reserves COM1 and LPT1 to refer to the first serial and parallel ports, respectively. ANALYZE CONFIGURATION Analyzing the configuration of the network can be accomplished in two different ways. The first and simplest way happens when the computer is turned on; the  operating  system  goes  out  and  checks  the configuration. The second way is accomplished by using an application to test whether a remote device is properly  connected  to  the  system.  The  use  of  an application is the best way to analyze the configuration. The application tests the remote device by sending out a signal to each device and waiting for the signal to return. This process is called “pinging.” The ping sent out is called an echo message, and the reply is called an echo reply message. The application sends out the echo message  and,  if  the  device  is  properly  connected,  it sends back an echo reply message. The receipt of this echo reply indicates that there is a viable connection. Some version of application software reports on how long it took to receive the echo reply and any lost replies. These reports provide information about the traffic and noise levels on the network. SYSTEM RESOURCE LIMITS The  advantage  of  a  network  is  it  allows  several people to share resources, both hardware and software. Hardware resources refer to printers, disk drives, CD- rom drives, scanners, and modems. Software resources include  operating  system,  drivers,  applications  (word processing, database, etc.), management software, and data files. To avoid problems, such as slow response time and unavailability of resources, you must know the limits of the system resources. Hardware Limits The limitation involved with hardware is going to be waiting. A particular piece of peripheral equipment can be accessed by one user at a time. Only one job can be printed at a time, and only one user can be using a single modem at a time. This small inconvenience of access outweighs the cost of several different pieces of the same type (i.e., several printers or modems). Software   Limits No matter  which  software  package,  whether application, mail, or operating system, there is a limited number of users that can use the software at one time. It is far cheaper to buy one multi-user package that allows for 25 users than to purchase 25 individual copies. But, it might run just a bit slower than an individual copy. NETWORK SOFTWARE Networks require the interaction of software and hardware. The system software to operate and control the network must be specifically designed for network operation. The application software/programs to solve user problems must also be specially designed to run on a  network.  Between  the  system  software  and  the application software/programs, two pieces of software are needed. One is the telecommunications access software. It provides application programs access to the network so they can send and receive data. The other  is  the  teleprocessing  monitor,  which  is  the interface  between  the  telecommunications  access software and the application programs. It handles the details of integrating these two. To install the system software, as with any software, follow the installation instructions supplied with the software. SYSTEM SOFTWARE It takes special system software to handle the unique and dynamic workloads of a network. This special  software  is  called  network  system  software. The network system software is sometimes referred to as the network operating system (NOS). It is different from the type of system software you normally use on your stand-alone PC. Network system software must be able  to  handle  multiple  users,  multiple  peripherals, network security, and be able to share information and application software, just to name a few differences. Normally, network system software runs on the network server.  It  includes  such  things  as  the  network’s operating system software, communications software, and all the programs needed to manage the sharing of information and resources on the network. Without it, there would be no way to coordinate and manage the many components of a network into a functioning whole. Network  system  software  provides  multitasking capabilities. If the network is to serve multiple users at the same time, then the server must be able to perform tasks   so   fast   they   appear   to   be   processed 1-6