network subnet / bit

varun_saa · 09-10-2005, 10:47 PM

Hello,
I have a network subnet of 192.168.0.0.
I have been entering config as 192.168.0.0/24.

I am not really clear about this bit issue.

How to decide wether it is :

192.168.0.0/24 or 192.168.0.0/16

Where can read more about this ?

Thanks in advance

Varun

Thoreau · 09-10-2005, 10:51 PM

http://www.netfilter.org/documentati...entation-howto

iptables doesn't like abbreviations of your subnets. It's not IOS.

Matir · 09-10-2005, 11:39 PM

Thoreau: why do you say iptables does not like abbreviations of his subnets? Which abbreviations do you refer to? IOS is, as far as I know, a Cisco thing.

varun_saa: It's really up to you. If you need <=254 IPs, use /24. If you need >254 & <=65534 IPs, use /16. Just be consistent.

Thoreau · 09-11-2005, 12:24 AM

Matir: If he's putting in route statements via iptables, you need to put in the fully qualified statement. Putting in class C and B /24 /16 hasn't worked in practice for me. Although, I don't know what the guys doing so we could be talking about the wrong topic entirely.

varun_saa · 09-11-2005, 12:51 AM

This was just a general knowledge question.
Just for the basics.
Not in iptables context.

Thanks

Varun