Unintended Consequences of NAT Deployments with Overlapping Address Space
Pyda Srisuresh and Bryan Ford
IETF RFC 5684
February 2010
Abstract:
This document identifies two deployment scenarios that have arisen
from the unconventional network topologies formed using Network
Address Translator (NAT) devices. First, the simplicity of
administering networks through the combination of NAT and DHCP has
increasingly lead to the deployment of multi-level inter-connected
private networks involving overlapping private IP address spaces.
Second, the proliferation of private networks in enterprises, hotels
and conferences, and the wide-spread use of Virtual Private Networks
(VPNs) to access an enterprise intranet from remote locations has
increasingly lead to overlapping private IP address space between
remote and corporate networks. This document does not dismiss these
unconventional scenarios as invalid, but recognizes them as real and
offers recommendations to help ensure these deployments can
function without a meltdown.