Providing Open Architecture High Availability Solutions

Providing Open Architecture High Availability Solutions
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Management middleware – The software within a system responsible for managing that system.
This software is typically provided as a separate package, although some operating systems may
also provide these functions.
Mean time to failure (MTTF) – The average time between one failure and the next one as
measured (or projected) over a large number of failures.
Mean time to repair (MTTR) – The average time it takes to repair a component or system as
measured (or projected) over a large number of repairs.
Media access controller – The device within a network controller just above physical layer which
provides the physical address and access control.
Memory management unit (MMU)– A hardware unit on a CPU which translates virtual
addresses to actual physical addresses in a system. It allows multiple programs to be written
assuming the same address space, and then assigns that physical address space upon running that
program. A MMU also prevents one program from over-writing another.
Methods – In object-oriented system design, methods are the functions that an object can perform.
See also Attributes.
MIB – see Management Information Base.
MMU – see Memory Management Unit.
MTTF – see Mean Time To Failure.
MTTR – see Mean Time To Repair.
N+M redundancy – A system that has N components working in normal operation and has M
components in standby. This is frequently reduced to N+1, where there is one standby component
for every N operational components.
Node – Component of a system which itself is a complete computer system, containing hardware,
operating system, and communications capabilities.
OAM&P – Operation, Administration, Management and Provisioning; the standard set of
functions needed to control a system.
Off-line Diagnostics – Diagnostics which are run on a component with either that component or
the entire system not operational. Off-line diagnostics are typically run to verify that a component
is working correctly before putting it into service. They are also run to determine the detailed cause
of a failure.
OMG – Object Management Group, a standards body working with object oriented design of
computer systems. The OMG is responsible for CORBA.
Open architecture – An architecture in which the interfaces are well defined and available for
anyone to use. Open architectures promote diversity and best-of-breed solutions due to
competition, they also give engineers the ability to focus on solving problems instead of porting
code.
Out-of-band communication or message – Transferring information over a special
communications channel or bus, usually reserved for control or management purposes.