Like this CertiGuide? Get it in PDF format!
Click Here!
Use coupon code "certiguide" to save 20%!
(Expires 2004/12/31)

NEW! Network+ N11-003 2005 Beta Exam Study Guide - Just $9!
Get It Here!

Custom Search







Table Of Contents  CertiGuide to Network+

Previous Topic/Section
Base 16
Previous Page
Pages in Current Topic/Section
1
2
Next Page
Appendix D: Graphics
Next Topic/Section

Appendix C:  Subnet Masks
(Page 2 of 2)

Custom Subnet masks

Not all subnets are made up of 255 and zeros. The Class A subnet shown above allows 16,777,216 unique devices (hosts). That is quite a bit of network traffic. To keep things flowing more smoothly an network can be divided into separate physical areas, and traffic can be divided by group or geography. For example finance and engineering. To break this single Class A address into two physical areas, the subnet 255.192.0.00 would be created. One for engineering, the other for finance.

The subnet would look as shown in Figure 63.

Figure 63: Sample Subnet Identifier

 


The 192(11000000) creates two custom subnets (at the network layer)

In this case IP host addresses were borrowed to create separate physical spaces. This reduces the number of available host addresses by 2 bits. Going with 255.224.0.0 creates three physical subnets, and further reduces the number of hosts. Perhaps you may wish to think of IP addresses as a pie. You can create more slices and serve more individual pieces if you cut more and serve smaller pieces. However, 32 bits is 32 bits. Just like the pie, it all is determined in how you slice it.


Previous Topic/Section
Base 16
Previous Page
Pages in Current Topic/Section
1
2
Next Page
Appendix D: Graphics
Next Topic/Section

If you find CertiGuide.com useful, please consider making a small Paypal donation to help the site, using one of the buttons below. You can also donate a custom amount using the far right button (not less than $1 please, or PayPal gets most/all of your money!) In lieu of a larger donation, you may wish to consider buying an inexpensive PDF equivalent of the CertiGuide to Network+ from StudyExam4Less.com. (Use coupon code "certiguide" by December 31, 2004 to save 20%!) Thanks for your support!
Donate $2
Donate $5
Donate $10
Donate $20
Donate $30
Donate: $



Home - Table Of Contents - Contact Us

CertiGuide for Network+ (http://www.CertiGuide.com/netplus/) on CertiGuide.com
Version 1.0 - Version Date: November 7, 2004

Adapted with permission from a work created by Tcat Houser and Helen O’Boyle.
CertiGuide.com Version © Copyright 2004 Charles M. Kozierok. All Rights Reserved.
Not responsible for any loss resulting from the use of this site.