Networking Bible

Chapter 4. Network Discovery and Mapping

IN THIS CHAPTER

• The methods used to browse networks

• The properties of connections are described

• How SNMP is used to manage network devices

• Network mapping

Network discovery is the way systems and devices are located on a network. There are various mechanisms that are used to enumerate devices, including node advertisement or broadcasting, browse lists, polling, and direct connections. Many times, combinations of these approaches are used. These different approaches are protocol independent, although many protocols are developed with a particular method of discovery in mind.

Network discovery uses a separate set of processes and protocols from name resolution. In order to be useful, both must work properly on a network. The methods used to look up names on a network are described. They include checking the HOSTS file; doing a DNS lookup; checking the NetBIOS name cache, WINS servers, and ARP broadcasts; and checking the LMHOSTS file.

A network connection is a defined path with two endpoints. Different types of network connections can be defined. Paths (or circuits) and endpoints can be either physical or virtual devices. A private circuit or channel can also be defined that is the basis for virtual private networks. Connections can be either stateful or stateless. A stateful connection retains the definition of a connection during and sometimes between sessions. Stateless connections are used when the path isn't defined.

Simple Network Management ...