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New Member

Using NAT and one public IP on the same ethernet interface


I'm a network administrator and I need some advice.

I have a small network with a Cisco 2516 router, several servers and

lots of hosts. I also have a small range of public IP. I can't give a

public IP to every host, because I don't have enough. So, the question

is How can I organize the network?

I have thought two possibilities:

A: Using NAT for servers and hosts. Static NAT for Servers, and

NAT-PAT for hosts. This can improve network security, but the servers

need to use multimedia, and I don't know if there could be some

problems with NAT and ports. In this case, I will use an Ethernet

inteface as usual.

B: Configure two subinterfaces on Ethernet interface, with two

different addresses. Host will use private address and router will do

NAT . The other address will be public and the servers will have

public addresses. Do you know if this could be possible?

Which one could be possible or better?

Thanks in advance


New Member

Re: Using NAT and one public IP on the same ethernet interface

this is the way i would do it. Use a private class address for your host and severs. I assume you have connection to the internet. Use NAT and PAT for your outgoing connections to the internet. For devices accessed from outside the network use static nat.


Re: Using NAT and one public IP on the same ethernet interface

A looks to be simpler to implement. You can try it first and in case you encounter problems with protocols running on your servers you can try B. With B you'll lose three of your valuable legal IPs (subnet address, subnet broadcast address and router interface address).

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