Network Instruments WAN Probe Kit - Manual (Page 36)

30 Analyzing a WAN Link with Observer
• Efficiency History
• Replay Packet Capture
Analyzing a WAN Link with Observer
In general, the WAN analysis works much like Ethernet analysis. One difference is that,
when appropriate, Observer identifies WAN links by their Data Link Connection Identifier
(DLCI) rather than by MAC address as is done with standard protocol analysis. In
addition, many WAN statistical modes break out the data by DCE, DTE, and summary to
reflect the full-duplex nature of WAN links. Modes unrelated to WAN analysis are greyed
out and unavailable.
The following sections describe how the available Observer modes operate to analyze a
WAN link.
Discover Network Names
To access this mode, choose Tools->Discover Network Names
Discover Network Names mode will show DLCIs instead of MAC addresses. You can
also define the Committed Information Rate for each DLCI you are monitoring with WAN
Observer.
Setting the Committed Information Rate (CIR) for a DLCI
The Committed Information Rate defines the guaranteed bandwidth for a WAN
connection. If you want Observer’s WAN Vital Signs and WAN Load by DLCI to monitor
CIR compliance, you must specify the CIR. A number of WAN triggers and alarms also
use this information, allowing you to be notified if the link is not performing to the CIR.