Now, let’s briefly discuss some of the more common network terms in the event you are not totally familiar with one or more of them so that when they are used on this website, you will understand them more clearly in the context in which they are used. These terms are:
LAN - Local Area Network. A group of PCs that make up a home PC network.
ISP - Internet Service Provider. Examples are AOL, Earthlink, MSN, etc.
IP Address - Internet Protocol Address. This is the language that computers use to talk to one another on the Internet or a network LAN. It is essential to know what an IP address and Internet Protocol is because understanding it and the components that make up the IP address is crucial to understanding how to properly secure your PC and/or network LAN. The IP address is represented by a series of numbers in groups of 4 separated by dots or a period. Examples of an IP address are: 192.168.1.1, 127.0.0.1, & 204.7.92.123. While connected to a network LAN, the IP address along with the fully-qualified Domain Name of your PC is how your PC is uniquely identified.
Static IP vs. Dynamic IP Address - A static IP address is one that remains fixed and never changes. The PC always sees the same address regardless if the session between the PC and ISP is broken or not. A Dynamic IP Address is one that changes over time or in the case of a Dial-up connection, when the user disconnects and reconnects to his/her ISP.
Internet - The worldwide Inter-Network. A collection of PCs and Servers worldwide that are interconnected into one massive network that can communicate with one another. The first primitive Internet was a collection of PCs used by the University of California at Berkeley and MIT professors called ARPANET. It was primarily formed to pass data back and forth in an efficient manner between institutions so that data sharing would be easier.
NAT - Network Address Translation - This is a means of hiding the IP addresses of PCs on a home LAN from the Internet while still allowing the PCs on the LAN to access the Internet. The process of hiding the IP addresses using NAT is called “masquerading.” This allows individual PCs on the LAN to have their own internal IP Address to the LAN while the Internet sees only the IP address that is provided by the ISP to the home network administrator.
TCP/IP & UDP Ports - TCP/IP refers to Transmission Control Protocol/Internet Protocol while UDP refers to User Datagram Protocol. Both are protocols (or languages, if you will) that allow PCs to communicate with one another and with the Internet as well as allow applications to communicate with each other on the PCs that make up the LAN and with the Internet. The term “Ports” refers to the number associated with each application that runs on PCs on a network and their usage allows these applications to access other PCs on the LAN and with the Internet itself. Some common port number assignments to applications are: Port 80 (http or web server applications); Ports 20 & 21 (ftp or file transfer protocol server applications), Port 25 (email applications), Port 23 (Telnet Services) and Port 53 (DNS or Domain Name System) just to name a few. If applications or services aren’t needed on the LAN or one or more PCs that make up the LAN, these ports can be and quite possibly should be turned off.
DNS - Domain Name System. This is the means by which web addresses are converted to IP Addresses on the Internet so that when a web address is typed into a web browser, it is converted to an IP Address and the web browser can locate the web server serving the web pages that are ultimately presented to you on your desktop.
Router - A network device that receives network data traffic and delivers it to other PCs on the network or from the Internet to PCs on a Local Area Network (LAN). Typical home user routers are devices manufactured by LinkSys, NetGear, 2Wire, etc. These devices allow the home network administrator to connect more than 1 PC to the Broadband service thus giving all PCs connected to the router their own connection to the Internet independent of any other PC on the network and not shared as is the case with ICS or Internet Connection Sharing where one PC receives the Internet connection and shares it with other PCs on a Workgroup LAN.
Firewall - A hardware device connected to a LAN or software program that runs on the PC (local client) that prevents network traffic from getting to your PC or certain applications to communicate with the Internet or vice versa. Both forms of firewalls allows the network administrator of the LAN to set policies in place that prevent access to or from the Internet or between PCs within a given network LAN.
Computer viruses - programs that take the form of payloads that may be benign or destructive that are created by hackers or other Internet ne’er-do-well programmers for the sole purpose of interfering with the PC and/or network LAN. These viruses when activated by clicking on an email or visiting a website can destroy data or hardware as well as send email messages without the sender’s consent or simply remain dormant for a time prior to launching.
Antivirus Software - Programs written by vendors like McAfee or Symantec Corporation to detect and remove viruses that are distributed on the Internet to home PC users. In most cases, this software can detect and remove the virus before it even infects the PC it was intended to infect.
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| This page was last modified on Friday, November 03, 2006 02:53 PM GMT-05:00 |