Netgear RT338 참조 가이드
Reference Guide for the Model RT338 ISDN Router
Configuring Filters
9-9
Reducing Unnecessary Calls by Microsoft Windows
One example of when to apply a filter set is reducing unnecessary calls by Windows
®
95 and
Windows 98. When using Windows with a dial-up ISDN router, you may need to make some
configuration changes to avoid having ISDN calls placed unnecessarily. Most of these
unnecessary calls are caused by PCs on the LAN trying to perform local NetBIOS name
resolution, either in response to a user action (browsing the Network Neighborhood or turning a
PC on or off, for example) or as periodic background activity. In some cases, this NetBIOS activity
can be kept local by other means, such as configuring a WINS or DNS server on the local network,
using an LMHOSTS file to store addresses of local hosts, or turning off NetBIOS name resolution
by DNS. A simpler method is to filter NetBIOS traffic using the filtering capabilities of your
Model RT338 router.
configuration changes to avoid having ISDN calls placed unnecessarily. Most of these
unnecessary calls are caused by PCs on the LAN trying to perform local NetBIOS name
resolution, either in response to a user action (browsing the Network Neighborhood or turning a
PC on or off, for example) or as periodic background activity. In some cases, this NetBIOS activity
can be kept local by other means, such as configuring a WINS or DNS server on the local network,
using an LMHOSTS file to store addresses of local hosts, or turning off NetBIOS name resolution
by DNS. A simpler method is to filter NetBIOS traffic using the filtering capabilities of your
Model RT338 router.
Diagnosing the Situation
If you already know the source or types of packets that are causing the problem, you can proceed
directly to the design of the filter. Otherwise, you can use a sniffer or the router’s built-in tools to
determine the source. A particularly useful tool is the display in Menu 24.1 of the “LAN Packet
Which Triggered Last Call.”
directly to the design of the filter. Otherwise, you can use a sniffer or the router’s built-in tools to
determine the source. A particularly useful tool is the display in Menu 24.1 of the “LAN Packet
Which Triggered Last Call.”
illustrates the header of the packet that caused an
unwanted call to be placed.
Figure 9-4.
LAN Packet Which Triggered Last Call
LAN Packet Which Triggered Last Call: (Type: IP)
45 00 00 3E 9E 05 00 00 1F 11 CC 9D 8D FB 17 12 CF 45 BC B9 00 89 00 35
00 2A 63 C8 01 85 01 00 00 01 00 00 00 00 00 00 0A 53 41 4E 54 41 43 4C
45 00 00 3E 9E 05 00 00 1F 11 CC 9D 8D FB 17 12 CF 45 BC B9 00 89 00 35
00 2A 63 C8 01 85 01 00 00 01 00 00 00 00 00 00 0A 53 41 4E 54 41 43 4C