Alcatel Carrier Internetworking Solutions Switch/Router 사용자 설명서

Page 19-61

An essential tool of the network engineer is a network packet capture device. A packet 
capture device is usually a PC-based computer, such as the Sniffer

®

, that provides a means for 

understanding and measuring data traffic of a network. Understanding data flow in a 

VLAN

-

based switch presents unique challenges primarily because traffic takes place inside the 
switch, especially on dedicated devices. 

The port monitoring feature built into OmniS/R software allows the network engineer to 
examine packets to and from a specific Ethernet 10BaseT port. Port monitoring has the 
following features:

• Software commands to enable and display captured port data.
• Captures data in Network General

®

 file format.

• Limited protocol parsing (basic IP protocols and IPX) in console dump display.
• Data packets time stamped.
• One port monitored at a time.
• RAM-based file system.
• Memory buffer space from 

1 MB

 to 

8 MB

.

• Statistics gathering and display
• Monitors only Ethernet 10BaseT ports
• Filtering limited to basic packet type—broadcast, multicast or unicast. 

You can select to dump real-time packets to the terminal screen, or send captured data to a 
file. Once a file is captured, you can FTP it to a Sniffer for viewing.

An alternate method of monitoring ports is Port Mirroring, which allows a network engineer 
to attach a Sniffer to one Ethernet port and mirror traffic to and from any other Ethernet port. 
Port mirroring is described in Port Mirroring on page 19-57.

The port monitoring commands are contained on the port monitoring menu, which is a sub-
menu of the Networking menu. The port monitoring menu displays as follows:

The commands in this menu are described in the following sections.