DESIGN solution required: Can (2) seperate external ip class C blocks from same ISP use a single internet link?

[Steve Coady]

Hello

In the process of a network integration between (2) compnaies. Company_A acquiring Company_B

Company_B has own centralized internet link with it's own external ip Class C block

Company_B will  get new external IP Class C thru same ISP as Company_A

Can (2) seperate ISP Class C blocks utilize the same Internet link within 1 company?

Is that a best practice.?

Company_A has a centralized internet link thru it's corprate site which consists of (3) buildings located in same City but seperated geographically.

2 Corporate sites have internet links. (1) link used as Primary, the other is the backup internet link.

From a design perspective it seems to make better sense if Company_B keeps an internet link for their Class C block with the possibility

that is Company_A internet link goes down, traffic could be routed out Company_B internet link and vice verse.

[Jon Marshall]

Steve

Your description of which company is getting what is a little confusing (at least to me) but to answer your specific question -

Can (2) seperate ISP Class C blocks utilize the same Internet link within 1 company?

Is that a best practice.?

Yes they can. As long as the ISP routes both address blocks to the company's internet facing router it will work fine. The actual public IPs do not need to be assigned to a physical interface, they can just be used for NAT statements on the router.

In terms of whether it is best pratice, well it's quite a common thing to happen because if a company runs out of public IPs rather than getting a whole new assignment and having to readdress or redo the NAT they simply get assigned another range to use.

Perhaps you could clarify the other bit ?

Jon