The type of binding expressed here. A given bit is set if DLCS
has detected that the two relevant items are bound together.
e.g. an entry with application2user(3) set to 1 implies that
the username extremeDlcsBindingUser has been seen to be using
the application extremeDlcsBindingApplication. In addition, if
this entry also has user2port(1) set to 1 then this user and
application have been detected as running on the physical
switch port extremeDlcsBindingPhysPort.