Data security in packet switched networks

The use of X.25 packet switching networks allows many channels to share one physical connection, and dynamically allocates bandwidth according to the immediate demands of each channel, including call management, without denying access to other channels. The paper outlines the categories of threat to data in such corporate X.25 environments, and includes a brief statement of the major security requirements needed to meet those threats. It identifies where security mechanisms, in particular data encryption, are most effectively applied within the ISO network architecture model. An overview of one of the most complex security issues in X.25 security-the key management problem-is presented, and an implemented solution is described. Some of the future possibilities for development in this area are also examined