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... separation are outlined in section 3.2.3. It is important to remember
that security is only as strong as the weakest link in the chain.
Several of the most publicized penetrations in recent years have been
through the exploitation of vulnerabilities ...
... ISDN, SMDS, DDS and Frame
Relay. All are provided via physical links which go through
telephone exchanges, providing the potential for them to be diverted.
...
... encryption (such as IPv6) are evolving rapidly;
consider using them on links where security is important.
...
...
This Reference Index contains a list of links to information
sources on Network and Computer Security ...