Network management

Definition

• Network management is the act (art) of initializing monitoring and modifying the operation of the primary network functions [Pras]
• Network management includes all the activities needed to keep the network running and evolving in such a way that it both satisfies the user needs and the provider constraints. [Festor]
• Network management determines the supervision of networked systems ensure that they behave according to some pre-defined goals [Stiller]
• A management system is a distributed system that monitors and controls another distributed system [Stadler]

Note, many more definitions exist:

• OSI Management Framework: OSI Management: the facilities to control, coordinate and monitor the resources which allow communications to take place in the OSI environment
• ITU-T E.410: International network management: the function of supervising the international network and taking action when necessary to control the flow of traffic Network management requires real-time monitoring and measurement of current network status and performance, and the ability to take prompt action to control the flow of traffic (http://www.itu.int/rec/T-REC-E.410/en).
• ITU M.3010: This recommendation presents the general architectural requirements for a TMN to support the management requirements of administrations to plan, provision, install, maintain, operate and administer telecommunication networks and services (http://www.itu.int/rec/T-REC-M.3010/en).
• ITS: The execution of the set of functions required for controlling, planning, allocating, deploying, coordinating, and monitoring the resources of a telecommunications network, including performing functions such as initial network planning, frequency allocation, predetermined traffic routing to support load balancing, cryptographic key distribution authorization, configuration management, fault management, security management, performance management, and accounting management. Note: Network management does not include user terminal equipment (http://www.its.bldrdoc.gov/fs-1037/dir-024/_3526.htm).

• die.net: The process of controlling a network so as to maximise its efficiency and productivity

Characteristics

• We can distinguish between managed systems ("system under management") and management systems
• Managed systems are always implemented in hard and software, management systems can additionally be implemented in terms of "brainware"
• Management involves activities of human beings
• Management decisions often operate on large timescales, lasting at least multiple round-trip times
• Management is performed in the operational phase, although management interfaces should be included in the design phase
• Management is defined under the system’s view, not by determining functions. This is due to the fact that functions may change all the time.

Management Automation

If the management functions are too complex or too expensive to implement them in hard / software, they can be provided by a human manager ("brainware"). If after some time the functions are better understood or cheaper to implement, it might be better (faster, less error-prone) to automate these functions and implement them in (hard or) software. In [pras] this process is described as the move from "explicit" to "implicit" management. In some network environments the goal may be to automate all management functions (and thus remove the need for a human manager / management); some people refer to this as Autonomous-management. In general complete automation may be impossible and some intermediate form may therefore be more realistic; some people refer to this as Autonomic-management.

Systems' View Points

• Sitting inside the system (network) – interior

Mini-view: Load balancing (controlled approach), resource sharing/allocation (controlled/managed mechanisms), error detection (automated), ...

• Sitting outside the system (network) – exterior

Maxi-view: “Security” (designed/managed by humans), optimal cost/operation benefits (calculated by IT – determined in-advance by humans), expansion decisions (supported by planning tools – decided by humans), ...