Why is IP range 225 invalid?

Posted on 2010-11-18
Last Modified: 2012-05-10
I have been asked to setup a secondary address in the range of  and found out if was invalid.   Why is this an illegal ip space and how can I find out more about it?   Google searches have not turned up anything as of yet.

Question by:DanRaposo
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Expert Comment

ID: 34165623

225 falls in class D ip address which is for multi casting
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Expert Comment

ID: 34165662


You cannot use this ip address for normal assignment which is reserved for multi casting.

Assisted Solution

Marvinlau earned 100 total points
ID: 34165700

the class D on networking, is used for multicast (communication with a group of computers), Its range is -

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Accepted Solution

moon_blue69 earned 400 total points
ID: 34165717
please find the attached guide

Author Comment

ID: 34166259
Great help guys ... before I accept and close can I ask for a bit more clarification?  In the Guide posted by Moon Blue69 it says

3.8.4 Class D And E Addresses
Class D networks are used for multicasting and do not contain network or host IDs. Multicasting is the process of sending a message simultaneously to more than one destination on a network. The first octet of a Class D address ranges from 224 to 239.
       Multicasting is often used to send information simultaneously to several registered hosts. A computer will register itself using a Class D address.

How do you register a computer with a Class D address if you cannot assign it to a NIC?

Author Comment

ID: 34166323
I found some interesting info ....

Thanks guys ...
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Expert Comment

ID: 34166358
You will have a class D ip address on multicast and you add the ip address of the participients of the multicast. You cast to one IP that is class D and the all the listed participients will recive it.

Hope this clarified it


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