Why All Networked PCs Need Anti-Virus Software

Many computer owners mistakenly think that if they run anti-virus software on the computer connected to the Internet then all PCs on the network are protected. However, if you use Microsoft’s Internet Connection Sharing (ICS) and Internet Connection Firewall (ICF)programs to share a DSL or cable modem line with several PCs, you need to use anti-virus to protect each PC. Even though only one PC is directly connected to the Internet, any system with Internet access is capable of accidentally downloading or opening virus infected files. For that reason, it’s absolutely imperative that you install a good anti-virus package on all of your computers.

Some people confuse the function of the anti-virus software with the function of a firewall. A single firewall is sufficient to protect an entire network, which is not the case with anti-virus software. That needs to be loaded on every system.

Both firewalls and anti-virus software provide protection, but that’s where the similarities end. The anti-virus software protects your PC and network from becoming infected with troublesome and sometimes destructive viruses. A firewall protects your entire network from unauthorized access into your network. This prevents intruders or hackers from accessing your personal information or from participating in a Denial of Service Attack on another company’s Web site.

Unfortunately, you do incur the cost adding anti-virus software to all your computers. But there is a plus side, the cost of anti-virus software has come down tremendously. For instance on Buy.com, the 2006 version of Norton Anti-virus sells for $34.99 with a $20 mail-in rebate for a total cost of only $14.99.
So for less then $30 you could upgrade two computers to the latest version of Norton for less then you paid for a single copy of your previous version. It’s definitely worth a few bucks for the added protection it provides. Believe me, the first time a virus infiltrates your system and erases your data, you’ll wish you had.


Tip for New Mac Owners
Many new Macintosh owners find themselves in unfamiliar waters when it comes to navigating the Mac OS. They quickly find that they don’t know how to perform even the most basic functions, like getting it online. If you’re in that category, here’s how to manually configure the IP address on my Mac.

Macintosh OS 7.5 to Macintosh OS 9.2




  1. Go to Apple > Control Panels > and down to TCP/IP.


  2. In the connect via field select Ethernet built-in, and then select
    Manually in the configure field.


  3. Type in your IP address, subnet mask, router address (Gateway), and
    name server address (DNS) in the boxes provided. Close out of the window and select OK to save your changes.


Macintosh OS X




  1. Go to Apple > System Preferences > and double-click on either of the Network icons.


  2. The first Configure field should read Ethernet built-in. The configure field under the TCP/IP tab should be set Manually.


  3. Type in your IP address, subnet mask, router address (Gateway) and
    name server address (DNS) in the boxes provided. Close out of the window and make sure to select Save to save your changes.



Ethernet Cables … How Far Will They Go?
The maximum length of Category 3, 4 or 5 twisted pair Ethernet cable that can be used between computers and other devices (such as hubs and switches) on a network is 100 meters or about 328 feet. You should keep in mind though that this is actually a theoretical limit and has such you would usually want to keep the distance between devices well below that.

If you are doing new construction or renovations, you also might want to consider bringing in a technician with a line tester to verify the integrity of the cable before you close up the wall, just to be on the safe side.

Adapted from PracticallyNetworked.com, part of the EarthWeb.com Network.

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