Following is a brief write up about the term project. There is a new
newsgroup (csd.cmsc417.term-project) for the project.  All postings
about the term project should go there.
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In order to understand what is required for the term project, you will
have to first read RFC 1459 (Internet Relay Chat Protocol (IRC)).
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e-CHIMP: e-CHIMP is the CMSC 417 Hierarchical IP-based Messaging Protocol.
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Concepts:
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   e-CHIMP users:  A named e-CHIMP communicating end-point.  The name of a
	user corresponds to IRC nicknames.
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   e-CHIMP group: A named set of e-CHIMP users (corresponds to IRC channel)
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   e-CHIMP clients: Local processes that e-CHIMP users use to
         correspond to other e-CHIMP users (equivalent to IRC clients).
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   e-CHIMP servers: e-CHIMP forms a two-level hierarchy.  The base-level
         consists of e-CHIMP clients.  e-CHIMP servers form the
         second-level in the hierarchy.  These are "transit" nodes that
         do not host users but act as message forwarders for e-CHIMP clients.
         Servers roughly correspond to IRC servers.
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   e-CHIMP routed network:  A set of e-CHIMP clients and servers.  Nodes in
         a e-CHIMP       routed network maintain route tables that indicate how
         to route messages to various e-CHIMP users using e-CHIMP servers.
         Unlike IRC, a e-CHIMP network does not have to be a tree; in
         fact, e-CHIMP networks should be able to "seamlessly"
         recover from connectivity failures and node faults.
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Implementation:
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   e-CHIMP clients connect to e-CHIMP servers using TCP.
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   e-CHIMP servers connect to each other using UDP.
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   e-CHIMP servers do not provide any guarantee about connectivity
         or reliability.  In this way, the e-CHIMP servers are much like
         IP routers.  e-CHIMP servers must detect link and node failures.
         e-CHIMP servers must also implement an "eventually consistent"
         routing protocol for e-CHIMP client messages.
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   e-CHIMP clients implement an end-to-end messaging protocol that
         ensures integrity and reliability.  The e-CHIMP end-to-end
         protocol does NOT have to implement congestion control but
         can implement flow control for extra credit.
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   e-CHIMP servers do not keep state about e-CHIMP users.  Their routing
         tables only contain entries about e-CHIMP clients.  e-CHIMP clients
         must implement a directory service protocol using which they
         can determine which client a particular user is currently connected
         to.  Messages sent from e-CHIMP clients contain both a
         destination e-CHIMP client id and an user id; however, en-route
         e-CHIMP servers ignore the user id and route based on the
         e-CHIMP client-id.  The user id is used at the destination client
         to demultiplex the e-CHIMP message to the proper user.
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   e-CHIMP users should be able to start an arbitrary number of "topics"
         corresponding to e-CHIMP groups.  All groups should eventually be
         "available" at all e-CHIMP clients.  (The directory service can
         be used to advertise groups and users).  Deletion of groups
         and private groups need not be implemented.  e-CHIMP users
         should be able to send individual messages to other users.