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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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3  
It is just slang. –  KCotreau Jul 26 '11 at 17:01
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then why should microsoft use 2 names for it ? –  SpiXel Jul 26 '11 at 17:05
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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 10.10.0.0/16 network (using CIDR notation). Here, your "network mask" is 255.255.0.0. 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 10.10.0.0/16, 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:

10.10.0.0/18
10.10.64.0/18
10.10.128.0/18
10.10.192.0/18

Here, your "network mask" is still 255.255.0.0, but each "subnet mask" is 255.255.192.0.

But, as I said, it's completely a relative term. One could also talk about 255.255.192.0 being a "network mask" and then 255.255.0.0 being a "supernet mask". For example, 10.10.0.0/16 is a supernet of, say, 10.10.64.0/18.

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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
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@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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