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A comment on Goodbye, IPv4 IANA Starts Allocating Final Address Blocks. Parent comment

Re:Goodbye, IPv4 IANA Starts Allocating Final Address Blocks by mgkimsal on Thursday May 22, 2014 @05:26PM (#7786664)
15 years ago I had to fill out an IP justification form - the justification was I had multiple SSL sites that all needed separate IP addresses. Wasn't a big deal, but was told it was standard practice (it was a smaller server center). And then I've had other dedicated server companies give me a block of 8 (5 usable) as just part of the monthly price.

What seems so wasteful is the "3 unusable" out of the 8 that are allocated. I have a vague understanding that those 3 are used for some routing/addressing stuff internally, but it's always felt incredibly wasteful.

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Re:Goodbye, IPv4 IANA Starts Allocating Final Address Blocks by q3k on Thursday May 22, 2014 @10:37PM (#7787733)
You can actually use two of these addresses (network & broadcast) - but you cannot really call it a proper /X block anymore. You will also have to make sure to disable the broadcast address you've used up on all of your hosts.

This is all very fuzzy and some admins will look at you weird for doing this - but sometimes you've gotta do what you've gotta do.

The third address (router) is actually used by your ISP's router's to reach your subnet.

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