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Whats the meaning of address of my computer (ip addr - command)?

  1. 1/24 and not 0/8

  2. 10.0.0 range and not 192.168.10

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if your computer is getting the address via dhcp, it means that the "box" handing out ip's is set up to use the 10 net. some soho routers use this, most use 192.168.?.0 /24. – dbasnett Jun 30 '10 at 13:49
up vote 16 down vote accepted

Thought I would expand on this with a few examples

/8 =

/16 =

/24 =

/32 = = is still in the same network as above we would have to go to to be on a different network. =

When you have a network you lose two IP addresses one for broadcast and one for the network. The first IP is reserved to refer to the network while the last ip of the range is reserved for the broadcast address.

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Thank you very much! – Yosef Jun 29 '10 at 21:40
According to RFC1878 "*Subnet all zeroes and all ones excluded. (Obsolete) *Host all zeroes and all ones excluded. (Obsolete) – dbasnett Jul 1 '10 at 13:12
@chris isn't = ? – Rajani Karuturi May 6 '14 at 15:08
@Rajani, I was looking over some of these old posts and you are correct. I'm surprised I even made this mistake at the time; thank you for pointing it out. – Chris Disbro Aug 21 '15 at 19:24

In addition to Tim's answer:

The /24 instead of /8 means that the first 3 octets of the ip address are used to specify the network. This is just a setting you can change if you want to. It's not super common to use the 10. private range with a /24 mask but there's no reason you can't do it.

/8 is using only the first octet to specify the network portion, which is what a 10. network explicitly meant back in the pre-CIDR days, and that's why you still see it more often with a /8 than with a 24.

As for the last octet being a 0 not a 1, that's because a would in this case be the network address, with being your computers ip.

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Thank you very much! – Yosef Jun 29 '10 at 21:40

RFC 1918 reserves 3 ranges for private IP addresses. Your DHCP server/router is configured to assign this range. - - -

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Thanks for answer 2, What about number 1. 1/24 etc... – Yosef Jun 29 '10 at 20:02
Sorry, didn't see that part. Dmatig answered above :-) So, your ip address is and the /8 subnet mask or – TD1 Jun 29 '10 at 20:28
I think you got the /8 and /24 from the post switched around /24 is /8 is :) – Chris Disbro Jun 29 '10 at 21:02
Thanks,Can you please explain to me more simple I dont know networks – Yosef Jun 29 '10 at 21:05
see… A subnet mask can also be represented in CIDR notation, like /8. /8 means because the first 8 bits equal 255. (think 8 binary 1's). Now from left to right if 24 binary ones and 8 0's were used we'd get /24 - – Dmatig Jun 29 '10 at 21:08

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