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Is there any logic in using two different names for determining host ID and net ID?

For example, if you type print route in a Command Prompt you get things with netmask, but the IPv4 settings seems to use subnet mask.

Is there any significant difference between the two terms?

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It is just slang. –  KCotreau Jul 26 '11 at 17:01
then why should microsoft use 2 names for it ? –  SpiXel Jul 26 '11 at 17:05
Why do we call William, Bill or Billy? We like to, and in some case, just lazy. The proper term is subnet mask, but they others are just used a lot, probably netmask more though. –  KCotreau Jul 26 '11 at 17:10

2 Answers 2

up vote 5 down vote accepted

The difference is very, very slight. 9 times out of 10, they will mean the exact same thing.

However, in cases where we're discussing the subnetting of a given network, the two terms "network mask" and "sub-network mask" can have distinct meanings. That is, if we make a distinction between a "network" and a "sub-network" then "the mask of a network" and "the mask of a sub-network" mean different things. In all cases, this distinction is almost purely a relative distinction.

Let's say you've been issued the network (using CIDR notation). Here, your "network mask" is Let's say you need to separate this network into 4 smaller networks, each as large as they could possibly be. In order to get 4 networks out of, you need to borrow two bits (00, 01, 10, 11) from the host address and use them for the subnet addresses. This will give you the following sub-networks:

Here, your "network mask" is still, but each "subnet mask" is

But, as I said, it's completely a relative term. One could also talk about being a "network mask" and then being a "supernet mask". For example, is a supernet of, say,

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The "Netmask", "subnet mask", or simply "mask" are all the same thing: A mask that tells software which IPs belong to that network an which don't.

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I dont think so , cause first of all , microsoft wont use different names for the same thing , and second of all , i've found the difference but i dont get what does it mean , I'll post it here as an answer –  SpiXel Jul 26 '11 at 17:00
(sorry couldnt self response)i've found this : Subnetting is the process of breaking down a main class A, B, or C network into subnets for routing purposes. A subnet mask is the same basic thing as a netmask with the only real difference being that you are breaking a larger organizational network into smaller parts, and each smaller section will use a different set of address numbers. –  SpiXel Jul 26 '11 at 17:03
what is a larger organizational network ? and what does it mean breaking it to smaller parts ? –  SpiXel Jul 26 '11 at 17:04
@SpiXel: Darth Android is correct. This is not really even up for debate. –  jftuga Jul 26 '11 at 17:06
@SpiXel: Dividing a network into smaller parts may consist of using VLANs to separate and/or isolate traffic, such as DMZs, servers, HR, Marketing, Developers, iSCSI, backups, etc. –  jftuga Jul 26 '11 at 17:08

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