Specifications

Models
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Requesters are the processes responsible for initiation of maintenance
operations. This can be done either at higher level user request, or
because of information obtained from a lower level. Requesters are
the active side of a maintenance operation.
Servers are the processes that respond to maintenance requesters.
They are the passive side of a maintenance operation. Servers should
not try to do more than they are capable of. For example, it
is not
acceptable to always volunteer.to load every system that requests it
and then take too long to get done because the local resources are
overextended.
The diagram shows servers and requesters as separate to represent
their functional independence. In an implementation that supports
multiple servers and/or requesters that use the same protocol type,
they may have to be more closely coupled so that messages received
through the data link are properly demultiplexed. Also, servers and
requesters that allow multiple users must further demultiplex messages
to the proper user processes.
The
Dump/Load Data Base contains default information that the
Dump/Load Server uses to fill in necessary values in incomplete
requests.
Lines to the top of processes indicate flow of the control data that
initiates processing. Lines to the side indicate Network Management
control. The double horizontal line indicates data base access.
3 INTERFACES
The following sections describe the interfaces related to maintenance
operations. The function descriptions are in terms of subroutines
with input and output arguments. These subroutines are to be
understood as abstract, functional descriptions. Actual
implementations may vary, for example in synchronization techniques,
as long as they provide the same functions.
References to buffers in all of the following subroutine descriptions
assume
a buffer descriptor containing buffer address, maximum buffer
length, and, if applicable, length of information in buffer.
3.1 Data Link Interface
Maintenance operations can be performed over communication channels
provided by different data link disciplines. All of the potential
data link user interfaces are abstracted into the functions required
for maintenance operations. This section describes that interface.
This section is included to define exactly what services a data link
must provide so that the low level maintenance functions can be
performed. It
is an abstract representation of all possible data link
interfaces, in terms that are directly applicable to low level