• Create BookmarkCreate Bookmark
  • Create Note or TagCreate Note or Tag
  • PrintPrint
Share this Page URL

Chapter 7. Networking > Networking Terminology

7.1. Networking Terminology

Understanding networking terminology is essential to making sense of the software and hardware used to assemble a network. The following terms are used throughout this chapter, as well as in just about any conversation about networking:


The capacity of a network connection to move information. If a network is capable of transferring data at 10 mbps, and two users are simultaneously transferring large files, each will only have about 5 mbps of bandwidth at their disposal. See Hubs and switches, later in this list, for limitations.


The technology upon which the vast majority of local area networks is built. A standard Ethernet connection is capable of transferring data at a maximum of 10 mbps, and a Fast Ethernet connection can transfer data at 100 mbps. A device capable of communicating of both speeds is typically labelled "10/100."


A layer of protection that permits or denies network communication based on a predefined set of rules. A firewall can be used to restrict unauthorized access from intruders, close backdoors opened by viruses and other malicious applications, and eliminate wasted bandwidth by blocking certain types of network applications. Windows XP includes a rudimentary firewall feature, described in Section 7.2.5, later in this chapter.

Hubs and switches

Devices on your network to which multiple Ethernet connections (called nodes) are made. See Figure 7-1 for an example. The main difference between a hub and a switch is a matter of performance (and cost). A switch is capable of handling multiple, simultaneous, full-bandwidth connections, while the less expensive hub throttles all connections such that, for example, three simultaneous connections can only each use one third of the total bandwidth.

IP address

A set of four numbers (e.g., corresponding to a single computer or device on a TCP/IP network. No two computers on a single network can have the same IP address, but a single computer can have multiple IP addresses. Each element of the address can range from 0 to 255, providing 256^4 or nearly 4.3 billion possible combinations. Network Address Translation (NAT) is used to translate an address from one network to another. This is useful, for example, when a LAN is connected to the Internet. On the Internet, dedicated machines called nameservers are used to translate named hosts, such as www.microsoft.com, to their respective numerical IP addresses. See Windows IP Configuration and NSLookup, both in Chapter 4, for more information.


Local Area Network, a designation typically referring to a network contained in a single room or building.


Mega-Bits Per Second, the unit of measure used to describe the speed of a network connection. Ethernet-based networks can transfer data either up to 10 mbps or up to 100 mbps. High-speed T1, DSL, and cable modem connections typically transfer data up to 1.5 mbps, while the fastest analog modems communicate at a glacial 56 kbps, or 0.056 mbps.

Since there are eight bits to a byte, you can determine the theoretical maximum data transfer rate of a connection by simply dividing by 8. For example, a 384 kbps connection transfers 384 / 8 = 48 kilobytes of data per second, which should allow you to transfer a 1 megabyte file in a little more than 20 seconds. However, there is more going on than just data transfer (such as error correction), so actual performance will always be slower than the theoretical maximum.


Network Interface Card, commonly known as an Ethernet Adapter. If your computer doesn't have built-in Ethernet, you'll need a NIC to connect your computer to a network. For Desktops, your NIC should be a PCI card; for laptops, your NIC should be a PCMCIA (PC Card) card. Universal Serial Bus (USB) based NICs can also be used with both desktops and laptops.


A number representing the type of communication to initiate. For example, web browsers typically use port 80 to download web pages, so web servers must be "listening" at port 80. Other commonly used ports include port 25 for sending email (SMTP), port 110 for retrieving email (POP3), port 443 for accessing secure web pages, port 21 for FTP, port 23 for Telnet, port 22 for SSH, port 53 for DNS, port 119 for newsgroups, and port 6699 for peer-to-peer file sharing applications (such as Napster).


Point-to-Point Protocol, a protocol used to facilitate a TCP/IP connection over long distances. PPP is used by Windows to provide an Internet connection over ordinary phone lines using an analog modem. Some DSL and cable connections use PPPoE (PPP over Ethernet), discussed later in this chapter.


A protocol is the language, so to speak, that your computer uses to communicate with other computers on the network. These days, the TCP/IP set of protocols is the de-facto standard for local area networks, and is required for Internet connections.


Shorthand notation for the collection of protocols that includes Transmission Control Protocol (TCP), Internet Protocol (IP), User Datagram Protocol (UDP), and Internet Control Message Protocol (ICMP). TCP/IP is required for all Internet connections, and is the standard protocol for most types of modern LANs.


The physical layout of your network. See the next section, Section 7.1.1, for more information on how topology comes into play.


Wide Area Network, or a network formed by connecting computers over large distances. The Internet is an example of a WAN.


Another name for a peer-to-peer LAN.



Not a subscriber?

Start A Free Trial

  • Creative Edge
  • Create BookmarkCreate Bookmark
  • Create Note or TagCreate Note or Tag
  • PrintPrint