network
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In many remote access scenarios, a mechanism for making the remote
host appear to be present on the local corporate network is quite
useful. This may be accomplished by assigning the host a "virtual"
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... 6]-[9] is a protocol suite defined to secure
communication at the network layer between communicating peers.
Among many applications enabled by IPsec ...
... host is then configured in such a
manner so as to provide it with a virtual presence on the internal
network. This is accomplished in the following manner:
A remote host ...
... the remote host with an address from the corporate network address
space. The remote host subsequently uses this as the source address ...
... remote host when using the assigned
address appears to the corporate network as though it were situated
behind a security gateway bearing the original routable IP address ...
... IPv4 address of the
interface supplying network connectivity, and an additional octet.
The x'4000' value indicates a locally administered unicast MAC
address ...
... not be routed back and forth between the remote host and the security
gateway unless the external network and corporate network have a
consistent addressing ...
... remote host and the security
gateway unless the external network and corporate network have a
consistent addressing plan. In this case the private IP address ...
... security gateway may now filter traffic as it would if the remote
host were physically located on the corporate network.
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