Viavi Apex Enterprise G3-APEX-ENT-32T, User Manual

Page: 207 / 380

Introducing Probes
Chapter 4: About Probe Instances 207
Hardware > GigaStor,
Portable
probes, Probe
Appliances, 3rd
party hardware
Dual port
Ethernet Probe,
3rd party
hardware
Ethernet Single
probe, 3rd party
hardware
Installed
software >
Expert Probe Multi Probe Single Probe
Port bonding (page
326)
4
X
Remote decode of
GigaStor captures
X
Sends expert
summary & decode
packets
4
X
VoIP expert, APA,
ATA
5
X
1.
Buffers are sent to Observer where the decoding and analysis is performed. This is less efficient
than sending the expert summary and decode packets, which is available with Expert Probe.
2.
Simultaneous users are supported when each user has his own probe instance.
3.
Only available on hardware probes from VIAVI.
4.
Decoding and expert analysis are performed by the probe and a summary is sent to Observer
reducing network bandwidth use.
5.
Application Performance Analysis and Application Transaction Analysis. Applications are generally
OSI Layer7 applications like HTTP, FTP, RTSP, SMB, and so on.
How probes work with switches
The purpose of a switch is to isolate traffic to the local network, thereby
reducing the amount of traffic each device on that network must see and
process. Although a protocol analyzer puts a network interface card in
“promiscuous” mode, the analyzer only sees packets addressed to or transmitted
from the port that it is connected to on the switch.
To operate a probe in a switched environment, you must choose a method that
provides network visibility to the port where the probe is connected. Most
switches provide a function that “mirrors” all packets received or transmitted
from either a single port of interest (for instance, a server or router), or multiple
ports of interest. The mirrored traffic can then be captured or analyzed by
connecting your analyzer (or in this case, the probe) to the “mirror port” (which is
sometimes called a SPAN port).
Note:
Switches typically provide two options for configuring the SPAN/
mirror port settings. You can either use a command line interface (CLI) or
web-based interface included with your switch to set the port (or ports) to
be mirrored.
To SPAN/mirror ports, Observer can use SNMP to directly query your switch
and report port-based statistics or use RMON to report any internal RMON
statistics the switch may have. Selecting the method right for you depends on
your switch, and the level of detail you need to troubleshoot the problem at
hand. For packet capture, decode and Expert Event identification, only static port
mirroring provides all the information required for a complete picture of what is
happening on your network.