About Probes and Instances
Discover the basics of probes, probe instances and what type is right for you, and how probes work with switches.
As a network administrator, when something goes wrong on your network, seeing what is happening on the wire can quickly lead you to a solution. Use this guide to assist you with choosing, deploying, configuring, and using your probes. The probes, along with Observer software, let you see all traffic on the network to which it is connected. To monitor multiple networks from a single analyzer, probes must be installed at every point where network visibility is required.
Probes collect and report network traffic and statistics (usually from a switch) to an Observer. This enables you to detect and anticipate problems on both local and remote portions of the network. Probes gain insight and visibility into every part of the network, access remote networks as easily as local networks, eliminate the time and expense of traveling to remote sites, and speed troubleshooting.
A probe is a hardware device on your network running VIAVI probe instance software. Each hardware probe has at least one probe instance that captures packets from your network to analyze. The probe hardware device could be an appliance purchased from VIAVI or you could install the probe software on your own hardware.
The probe can be located on the same system as the analyzer (every Observer includes a “local probe”), or the probe can communicate with remote analyzers over TCP/IP.
Probes monitor the following topologies:
10/100 Mb, 1/10/40 Gb Ethernet (half- and full-duplex)
Wireless ( 802.11 a/b/g/n)
shows how probes provide visibility into your network. It may be obvious, but it also shows that you cannot see traffic on portions of your network where you do not have a probe. Finally, you can put Observer anywhere on your network so long as it has TCP connectivity to the probe.
 
Figure 69: Typical network