applicationname appinstanceid pam id u201d flexibility is the most significant advantage of using context keys over direct references to message caches the infrastructure of the application serving environment is free to associate a context key with whatever routing information is necessary to ensure availability and differentiation one alternative to the hierarchical naming convention would be to link a context key to a network port and use the context key itself to identify the message cache additionally new relationships may be formed among pams by creating new ha groups in this additional embodiment an exemplary naming convention would be u201c parallel applicationname appinstanceid groupname pam id u201d additional ha groups would allow pams to participate logically in various configurations based on the original group each additional group would logically have unique message caches related to the default group message caches alternatively the context key manager sets up a partition for each pam instead of an ha group of pams if a partition is used then the context key manager creates a context key for each partition links each partition to a context key and links each context key to a pam a partition may represent a message cache the partition router handles communications between pams fig1 illustrates the general operation of context key manager 900 in support of message passing between pams message.