1. Home
  2. Cisco Systems
  3. Conceptual question: Reasoning behind private subnetting scheme?

Conceptual question: Reasoning behind private subnetting scheme?

We have a geographically dispersed WAN. All of the offices have

192.168.n.0/24 local IP address. The point-to-point links between all of our routers are taken from the 192.168.65.0/24 network which has been subnetted into 64 two host subnets 192.168.65.0/30.

Is there a reason the engineer that set up our network chose the

192.168.65.0/24 network to subnet into the site-to-site links? Is this a standard or customary practice, or just his preference? Why not subnet 192.168.254.0 into the site-to-site networks?

I=92m just curious. I have looked all over and have not been able to find any documentation on customary use of private subnets in a situation like this. Is there a best practice defined somewhere?

Thanks, John

Reply to
John H.
Loading thread data ...

They just picked it out of thin air. There is no best practice to choosing IP addressing like this, it just happens.

Reply to
Doug McIntyre

Well err, there is a reason for choosing particular addresses.

If route summarisation is anticipated then it is a decent idea to chose addresses appropriately.

For example:-

192.168.0-63.x can be summarised into a single prefix.

Similarly 128-255.

So if 254 had been chosen then the opportunity to summarise 128-255 would have been lost.

So perhaps the original designer was thinking ahead:)

Reply to
bod43

Thanks Bob43. Route summarization makes since. That was the concept I was not seeing.

Reply to
John H.

Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.