Madge Networks 802.11b User Manual
For a wireless client computer to communicate with a correspondent host on the Internet by the host’s
domain name (e.g.
domain name (e.g.
), it first sends a DNS request to a DNS server on the Internet.
The DNS request travels first to the advanced AP, the advanced AP then relays this request to the default
gateway of the client computer. Finally, this request is forwarded by the gateway to the DNS server on
the Internet. The DNS reply issued by the DNS server is transmitted back to the client computer
following a reverse path. When the client computer receives the DNS reply, it knows the IP address of the
correspondent host and sends further packets to this IP address.
As illustrated in Fig. 26, the communication path could be broken at some of the stages. The OS-provided
network diagnostic tool, ping.exe, can be employed to find out TCP/IP-related communication problems.
gateway of the client computer. Finally, this request is forwarded by the gateway to the DNS server on
the Internet. The DNS reply issued by the DNS server is transmitted back to the client computer
following a reverse path. When the client computer receives the DNS reply, it knows the IP address of the
correspondent host and sends further packets to this IP address.
As illustrated in Fig. 26, the communication path could be broken at some of the stages. The OS-provided
network diagnostic tool, ping.exe, can be employed to find out TCP/IP-related communication problems.
NOTE:
If two or more NICs are installed and operating on a client computer, TCP/IP may not work
properly due to incorrect entries in the routing table. Use the OS-provided command-line network tool,
route.exe, to add or delete entries from the routing table. Or, use Windows-provided Device Manager to
disable unnecessary NICs.
Solve the following problems in order:
route.exe, to add or delete entries from the routing table. Or, use Windows-provided Device Manager to
disable unnecessary NICs.
Solve the following problems in order:
The advanced AP does not respond to ping from the client computer.
Are two or more NICs installed on the client computer?
Use the OS-provided command-line network tool, route.exe, to modify the contents of
the routing table.
Use Windows-provided Device Manager to disable unnecessary NICs.
the routing table.
Use Windows-provided Device Manager to disable unnecessary NICs.
Is the underlying link (Ethernet or IEEE 802.11b) established?
Make sure the Ethernet link is OK.
Make sure the wireless settings of the wireless client computer and of the advanced AP
match.
Make sure the wireless settings of the wireless client computer and of the advanced AP
match.
Are the IP address of the client computer and the IP address of the advanced AP in the same
IP subnet?
IP subnet?
Use WinIPCfg.exe or IPConfig.exe to see the current IP address of the client computer.
Make sure the IP address of the client computer and the IP address of the advanced AP
are in the same IP subnet.
Make sure the IP address of the client computer and the IP address of the advanced AP
are in the same IP subnet.
TIP:
If you forget the current IP address of the advanced AP, use Wireless Router/AP
Browser to get the information (see Appendix B-3).
The default gateway of the client computer does not respond to ping from the client computer.
Solve the preceding problem first.
Are the IP address of the advanced AP and the IP address of the client computer in the same
IP subnet?
If you cannot find any incorrect settings of the advanced AP, the default gateway may be
really down or there are other communication problems on the network backbone.
Are the IP address of the advanced AP and the IP address of the client computer in the same
IP subnet?
If you cannot find any incorrect settings of the advanced AP, the default gateway may be
really down or there are other communication problems on the network backbone.
The DNS server(s) of the client computer do not respond to ping from the client computer.
Solve the preceding problems first.
If you cannot find any incorrect settings of the advanced AP, the default gateway of the
advanced AP may be really down or there are other communication problems on the network
backbone.
If you cannot find any incorrect settings of the advanced AP, the default gateway of the
advanced AP may be really down or there are other communication problems on the network
backbone.
100-408-01
Copyright © 2002 Madge Networks. All rights reserved.
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