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Tech Note #37:  Introduction to the TOAD
TM
 Protocol
©
1998 Bionic Buffalo Corporation; All Rights Reserved.
                  12 June 1998
http://www.tatanka.com
Page 
7 of 13
request-
mode client
broadcast request
for objects of a
specified class
unicast response from
master node which
advertises availability of
objects on slave node
slave mode
server
master node
To request objects of a specific class, the Slave passes the requests to its Master. The
Master makes the choices for the Slave. Slave mode does not make use of broadcast
transmission.
Mode 6: Directed Mode
Directed Mode is similar to Slave Mode, except that the Directed Node serves multiple
Masters. When a Directed Node seeks objects, it may choose from among the objects
offered by its various masters.
A Directed node may be one of its own masters. In this case, the node may choose
between objects contained within itself, or objects advertised to it by its other servers.
Note that there is no “Master Mode”. There is no ultimate authority in this hierarchy: all
authority is contextual.
Internal Mode may be used in a non-networked environment for the advertising and discovery
of objects within a single node.
Request Mode and Advertising Mode are complementary. In Request Mode, the client
broadcasts requests for objects of a class, whereas in Advertising Mode, the server broadcasts
the availability of its objects.
Slave Mode is used for the complete subjugation of one node to another. Directed mode is
similar, but gives the Directed node some measure of autonomy. If several nodes are Directed to
one another as Masters, then the group operates similarly to a group of nodes in Broadcast,
Aggressive, or Passive Mode, except that the network traffic uses specific addresses instead of
broadcast addresses.