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network using public address space

Benjamin Waldon
Level 1
Level 1

Hi,

I just had a quick question and I wanted to check in with everyone before making a recommendation and finding out that I am totally wrong.

I am working with a new client. Their internal subnet is 192.0.0.0 /24. I am thinking that is totally messed up, because that it is public address space. Maybe they were assigned that range by the ISP, but I doubt it.

I checked on the RFC http://www.ietf.org/rfc/rfc1918.txt

At any rate, I plan on telling them tomorrow that they need to start a process of changing it to one of the 3 in the RFC.

Just to flesh out the conversation...

Is that illegal? what are the ramifications? Is seems to me that it's just a matter that if they try to talk to a host in that network, it isn't going to work.

Thanks,

Ben

1 Accepted Solution

Accepted Solutions

Jon Marshall
Hall of Fame
Hall of Fame

benwaldon wrote:

Hi,

I just had a quick question and I wanted to check in with everyone before making a recommendation and finding out that I am totally wrong.

I am working with a new client. Their internal subnet is 192.0.0.0 /24. I am thinking that is totally messed up, because that it is public address space. Maybe they were assigned that range by the ISP, but I doubt it.

I checked on the RFC http://www.ietf.org/rfc/rfc1918.txt

At any rate, I plan on telling them tomorrow that they need to start a process of changing it to one of the 3 in the RFC.

Just to flesh out the conversation...

Is that illegal? what are the ramifications? Is seems to me that it's just a matter that if they try to talk to a host in that network, it isn't going to work.

Thanks,

Ben

Ben

It's not illegal as such but you must ensure that none of that addressing leaks onto the Internet because you can then conflict with the real owners of the address space.

You are right in what you say ie. they will not be able to get to any external 192.0.0.x hosts, at least not without some fancy NAT

Jon

View solution in original post

1 Reply 1

Jon Marshall
Hall of Fame
Hall of Fame

benwaldon wrote:

Hi,

I just had a quick question and I wanted to check in with everyone before making a recommendation and finding out that I am totally wrong.

I am working with a new client. Their internal subnet is 192.0.0.0 /24. I am thinking that is totally messed up, because that it is public address space. Maybe they were assigned that range by the ISP, but I doubt it.

I checked on the RFC http://www.ietf.org/rfc/rfc1918.txt

At any rate, I plan on telling them tomorrow that they need to start a process of changing it to one of the 3 in the RFC.

Just to flesh out the conversation...

Is that illegal? what are the ramifications? Is seems to me that it's just a matter that if they try to talk to a host in that network, it isn't going to work.

Thanks,

Ben

Ben

It's not illegal as such but you must ensure that none of that addressing leaks onto the Internet because you can then conflict with the real owners of the address space.

You are right in what you say ie. they will not be able to get to any external 192.0.0.x hosts, at least not without some fancy NAT

Jon

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