Address Classes question | Coursera Community

Address Classes question


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In my Bits and Bytes of Computer Networking, week 2 in the quiz it asks how may addresses are in a class C, I went back to the class after my first answer was wrong. When I took the quiz again I guessed [removed by moderator], and got it right. I don’t understand how they came up with that number. In the course it says “For a Class C network, this comes out to 2 to the 8th or 256 addresses” but 256 wasn’t an answer option on the quiz.


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Userlevel 6
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Hello @mistyceaton 

This is because, Class C Networks defines a maximum of 2,097,152 (2 ^21 ) /24 networks. And each network supports up to [removed by moderator] (2 ^8 -2) hosts.

Therefore, the correct answer is [removed by moderator].

The entire class C network represents 2 ^29 (536,870,912) addresses.

It is only 12.5 % of the total IPv4.

 

Hope this helps.

Regards,

Saheli

Single IPv4 block/segment (with 24-bit mask) of Class C pool indeed offers 256 unique IP addresses.

In addition - why (2^8 -2) hosts? - you might ask.
Well, because in such networks, the IP address ending with x.x.x.0 is the entire “network address”, and the one ending with x.x.x.255 is the “broadcast address” - and they (usually) cannot be assigned to any single network interface card, thus only remaining [removed by moderator] IP addresses are available for addressing actual hosts in such networks.

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thank you

Userlevel 7

Hi everyone, please don’t share assignment answers, as it goes against our Honor Code. I have removed them now.

 

:D

Userlevel 6
Badge +11

Hi everyone, please don’t share assignment answers, as it goes against our Honor Code. I have removed them now.

Thank you @Jose A .

 

 

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