What does an IP ending in 0 signify?

When I tried to tell a norton firewall to allow traffic from the local network range, from 192.168.1.1 thru 192.168.1.149, it said, "IP already allowed".

I looked on the "allowed List".  The firewall's "network wizard" had already allowed this:  192.168.1.0

What does this mean? I don't think I've seen an IP ending in 0 before (sorry). Does the "0" signify a range from "1 thru 254"?  

If so -- does that apply in any of the 4 octets?
dgrrrAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Guy Hengel [angelIII / a3]Billing EngineerCommented:
a 0 at the end is like a wild-card, allowing all ip addresses in that range 1-254
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
r_naren22atyahooCommented:
angelIII is rite, adding to it

it is also called as network address

example
192.168.1.0 (this address is for whole network staring from 192.168.1 192.168.1.254)
255.255.255.0

in the same way for
192.168.0.0 is the network address for
255.255.0.0

regards
naren
0
thajuonlineCommented:
"The firewall's "network wizard" had already allowed this:  192.168.1.0"


this means that u'r firewall will allow all the address it the range 192.168.1.1 to 192.168.1.254

thanks
0
The--CaptainCommented:
A .0 address is meaningless without a corresponding subnet mask or CIDR notation - if your have a subnet wider than /24, an addressable host with an IP ending in .0 certainly exists.

That being said, I agree that the .0 address likely refers to the entire corresponding /24 subnet, since firewall manufacturers love to make their devices/software interpret the IP spec as creatively as possible, and their configuration interfaces are as brain-dead as possible...  

Regardless, it should be noted that the accepted answer is not correct for all cases.

Cheers,
-Jon
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Software Firewalls

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.