Managing the elements of a network is made difficult in large part by the proliferation of network management protocols. The proliferation exists because of the market momentum of earlier protocols, and because no single protocol can hope to simultaneously satisfy the occasionally conflicting requirements. Some of the more popular protocols are:

SNMP (Simple Network Management Protocol) is an IETF standard that is the most commonly implemented network management standard on the Internet. Besides IETF, information may also be found at http://www.snmp.com/.

Common Management Information Protocol/Guidelines for the Definition of Managed Objects (CMIP/GDMO) is an ITU network management protocol. It requires more resources on client and server to operate than SNMP, but provides a richer and better object-oriented basis than SNMP. It is still backed by many telecommunications vendors and carriers but some question its future now that CORBA has become so popular (see below). Information may be found at http://www.itu.int/

Transaction Language 1 (TL1) is a Network Element (NE) management language defined by Telcordia (formerly Bellcore) that is used primarily in North America in telecommunications equipment. It is ASCII based and designed to allow text entry of commands via a "craft" port (EIA232 or X.25 connector) by either a machine or "craftsperson". The response and autonomous message syntax was designed to be unambiguously parsed by humans and machines. Information may also be found at http://www.tl1.com/

QD2 is a German network management protocol. If you read German, you may find more information at http://www.teleconnect.de/Users/altj/QD2.htm or contact tssinfo@de.bosch.com.

Common Object Request Broker Architecture (CORBA) is an object oriented remote-procedure-call (RPC) protocol. While not designed specifically for network management, it is now considered a more widely available and less expensive alternative to CMIP/GDMO for NEs whose management requirements can not be easily met by SNMP or TL1. Information may be found at http://www.omg.org/

Hyper Text Markup Language/Hyper Text Transfer Protocol (HTML/HTTP) is starting to show up in IP equipment, such as network ready printers. Try pointing a web browser at a recent HP laser printer if you have one on your network - it probably has a web server running on it, along with an SNMP agent too! Information may be found at http://www.w3.org/

Extensible Markup Language/Simple Object Access Protocol (XML/SOAP) is also becoming popular. XML is sometimes used in conjunction with CORBA. Information may be found at http://www.w3.org/

There are many proprietary protocols. Here are some that Lugoj has direct experience with:

• Telemetry Byte Oriented System (TBOS) is a very simple alarm and control protocol. Information may be found at http://www.tbos.net.

• Badger and Larse low baud rate serial protocols for control and monitoring of, for example, microwave sites. Some information might still be found at http://www.badger.com or http://www.larse.com.