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Next: Delay and Loss Up: 33.3.1 Object Linkage Previous: Nodes and Links Session Helper

Each active source in a session requires a ``session helper''. The session helper in is realised through a replicator. This session helper is created when the user issues a []create-session to identify the source agent. The simulator itself keeps a reference to the session helper in its instance variable array, session_, indexed by the source and destination address of the source.

Note that the destination of source agent must be set before calling []create-session.

SessionSim instproc create-session { node agent } {
    \$self instvar session\_

    set nid [\$node id]
    set dst [\$agent set dst\_]
    set session\_(\$nid:\$dst) [new Classifier/Replicator/Demuxer]
    \$agent target \$session\_(\$nid:\$dst) # attach the replicator to the source;
    return \$session\_(\$nid:\$dst) # keep the replicator in the SessionSim instance variable array {\tt session\\_};