3.2. Identifying Capabilities Clients Need to Use Network Resources
For two computers to communicate over a network, they must have three components in common. It is essential that you understand the role of these components so you can design, manage, and troubleshoot networks.
3.2.1. Critical Information
A computer connection over a network requires a common media, a common protocol, and a common client or service. In this section, we discuss each of these subjects in detail.
3.2.1.1. Common Network Media
"Network media" is a loose term for anything that is connecting two computers together to form a network. This can be cables and wires or wireless communication such as Wi-Fi access or even infrared light. The main requirement in order for the network media to be effective is that the computers that are going to communicate share the network media in common. In other words, just because one computer can connect with a cable and another computer can connect with a radio signal does not mean that the two computers can connect to each other. In fact, just because two computers can connect with a wireless connection does not mean that they can connect to each other. However, if two wired computers are connected to a common hub or if two computers are connected with a wireless connection and share the same frequency, then they have a chance at connecting to each other, assuming that all of the other components are present.
3.2.1.2. Common Protocol
Most computers in use today share the common protocol of TCP/IP. This is because TCP/IP has become the de facto standard protocol for communication on the Internet. Whether TCP/IP is chosen as the common protocol between two computers, or some other protocol, such as IPX/SPX or AppleTalk, is chosen, the main requirement is that both computers share the same protocol and that the protocol be configured properly to allow the computers to communicate with each other. In regard to TCP/IP, this can be accomplished with manual configuration, or special servers and services can automatically configure the protocol address. Other protocols are self-configuring; an example is IPX/SPX, which uses the MAC address of a computer to complete the configuration.
3.2.1.3. Common Client
The term "client" can sometimes be a confusing one because it's used interchangeably to refer to a client computer, a client operating system, and sometimes even a person (as in "a client of a law firm"). Still another use for the term "client" is the networking software that is used to connect computers. The type of client used will depend completely on the vendor of the operating system software, but it's not quite that simple either.
Vendors such as Microsoft and Novell provide client software that can be used to connect to their servers and use resources. The services called CSNW and GSNW (which we discussed earlier in the chapter) are actually clients that Microsoft provides, which can be added as a second client to the Microsoft Client software included with the Microsoft operating system. Like-wise, Novell "clients" are just computers with another type of operating system installed first (Novell does not make an operating system that runs a client PC) and then followed up with an installation of Novell client software.
3.2.2. Exam Essentials
List the requirements for common network media. The media that computers use is not important in regard to their ability to communicate with each other, only the fact that the media must be common between the computers. A common network media is a cabled media or a wireless media. Some computers have multiple connections that allow more than one type of media on the same computer.
Know the requirements for a common network protocol. A protocol is like a language that computers use to communicate within a network. The main requirement of a common network protocol is that the two computers use the same protocol and that the protocol be configured properly for connectivity. The most common protocol used for network connectivity is TCP/IP, but many more protocols are in use today.
Understand the requirements for a common network client. The type of client that you use will largely depend on the vendor of the client operating system that you choose. Microsoft operating systems come installed with a client called Microsoft Client. Some vendors also provide client operating system software that allows their clients to communicate with the servers and clients of other vendors.