Using rule-based decisions for selective control of proxy connections
Original Publication Date: 2001-Mar-01
Included in the Prior Art Database: 2003-Jun-11
When a change is made, by an administrator, to the configuration of an Internet Protocol "proxy", it is usual practice to close all current connections through the proxy, make the change, and then allow the connections to be re-established under the new configuration regime. This invention allows the possibility that some or all of the current connections can remain in progress during and after a change to the proxy configuration. The proxy to which this invention is applicable is a system which allows for the configuration of a number of predefined "routes". These are specifications of remote servers to one of which the proxy will connect when it receives a connection request from a client system. Each of these "routes" has a set of parameters which affect its behaviour and indicate certain modes of operation for that route. Reconfiguration is performed by editing a configuration file, which the proxy reads at startup, and subsequently when told to re-read it by a special "reconfigure" signal sent by the administrator to indicate that a change has been made to the file. When asked to re-read the file, the proxy compares the configuration options for each route in turn, against the settings that it is currently using on the running system. For any given route, the changes are noted, and a test is applied to determine if the change to each particular parameter, in the context of the current activity state of that route, requires a closing of currently active connections and subsequent re-establishment of those connections, or if the change to that parameter can be effected without forcing the closing of connections. Clearly the latter is a desirable outcome, since the intent is to provide a continuous service as far as is reasonably possible.