SONETnetwork management protocols

There are some features that are fairly universal in SONET Network Management. First of all, most SONET NEs have a limited number of management interfaces defined. These are:

Electrical interface. The electrical interface (often 50 Ω) sends SONET TL1 commands from a local management network physically housed in the Central Office where the SONET NE is located. This is for "local management" of that NE and, possibly, remote management of other SONET NEs.
Craft interface. Local "craftspersons" can access a SONET NE on a "craft port" and issue commands through a dumb terminal or terminal emulation program running on a laptop. This interface can also be hooked-up to a console server, allowing for remote out-of-band management and logging.

SONET and SDH have dedicated data communication channels (DCC)s within the section and line overhead for management traffic. Generally, section overhead (regenerator section in SDH) is used. According to ITU-T G.7712, there are three modes used for management:Dual (IP+OSI) stack using PPP or LAP-D with tunneling functions to communicate between stacks.An interesting fact about modern NEs is that, to handle all of the possible management channels and signals, most NEs actually contain a router for routing the network commands and underlying (data) protocols.

The main functions of network management include:Network and NE provisioning. In order to allocate bandwidth throughout a network, each NE must be configured. Although this can be done locally, through a craft interface, it is normally done through a network management system (sitting at a higher layer) that in turn operates through the SONET/SDH network management network.Software upgrade. NE software upgrade is in modern NEs done mostly through the SONET/SDH management network.

Performance management. NEs have a very large set of standards for Performance Management. The PM criteria allow for monitoring not only the health of individual NEs, but for the isolation and identification of most network defects or outages. Higher-layer Network monitoring and management software allows for the proper filtering and troubleshooting of network-wide PM so that defects and outages can be quickly identified and responded to.