Business applications running on a content delivery network (CDN) having a
distributed application framework can create, access and modify state for
each client. Over time, a single client may desire to access a given
application on different CDN edge servers within the same region and even
across different regions. Each time, the application may need to access
the latest "state" of the client even if the state was last modified by
an application on a different server. A difficulty arises when a process
or a machine that last modified the state dies or is temporarily or
permanently unavailable. The present invention provides techniques for
migrating session state data across CDN servers in a manner transparent
to the user. A distributed application thus can access a latest "state"
of a client even if the state was last modified by an application
instance executing on a different CDN server, including a nearby
(in-region) or a remote (out-of-region) server.