Ip subnet zero

[muddyfox1009]

Hi, i started learning subnetting before the new cisco update comes into force last year. Now Cisco has introduced the ip subnet zero. What I would like to know is , is this why I am now getting two less subnets in the networks?
For example for class c / 240, i am now getting 16 subnets and 14 hosts. Previously before the ip subnet zero was introduced I will get 14 subnets and 14 hosts. Is this the result of ip subnet zero?

I hope I'm correct in this because i'm so used to the previous non-ip subnet zero, that i'm making mistakes all over. Please help.

[dbeare]

The ip subnet-zero concept is nothing new and has been supported by Cisco routers for quite some time. It is, in practice, the main difference between concept and practice. The reason that it is said to not use it is that we don't want to use IP's with an actual subnet of all 1s or 0s, the first and last subnets. In practice, both of these subnets has always been available to use. Starting with the 12.0 IOS release, ip subnet zero has been set as default on the routers, allowing for use of these subnets. On prior IOS's, the command can be entered in manually in the global configuration mode. Here is a great link from Cisco that gives some information on how subnet zero works:

http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080093f18.shtml

[muddyfox1009]

Thanks dbeare. I'll finding the time to digest this.

[chapsman]

u're right having 16 subnet theyare using ip subnet zero
because the first and last number are consider