This document provides a sample configuration of a wireless LAN (WLAN)
on a Cisco 1800 Integrated Services Router (ISR).
There are no specific requirements for this document.
The information in this document is based on these software and
1800 ISR on Cisco IOS® Software Release 12.3 or later with the
Advanced IP Services feature set
Note: You can apply the same configuration to any of the ISRs. The
configuration is not specific to the 1800 series.
PC with these wireless network cards:
The information in this document was created from the devices in a
specific lab environment. All of the devices used in this document started with
a cleared (default) configuration. If your network is live, make sure that you
understand the potential impact of any command.
Technical Tips Conventions for more information on document
In this section, you are presented with the information to configure
the features described in this document.
Note: Use the
(registered customers only)
to find more information on the commands used in this
This document uses this network setup:
Wireless Connection to the Router
Complete these steps:
Set up the DHCP scope and excluded addresses.
Note: Excluded addresses are optional.
IOS DHCP Server for a more detailed explanation of the DHCP server in
Cisco IOS Software.
Turn on integrated routing and bridging, and set up the bridge
Assign an IP address to interface Bridge-Group Virtual Interface 1
Set up wireless.
Assign interface Dot11Radio0 or Dot11Radio1 to bridge group
Assign a service set identifier (SSID) to the radio interface,
and then define open authentication.
This document uses this configuration:
1800 Series ISR Wireless and DHCP Configuration
!--- Output suppressed.
ip dhcp excluded-address 192.168.2.1 192.168.2.100
!--- This sets up DHCP and excluded addresses. Excluded addresses are optional.
ip dhcp pool 1800-ISR
network 192.168.2.0 255.255.255.0
!--- Turn on integrated routing and bridging.
!--- This is the wireless radio interface configuration.
no ip address
!--- Here, the SSID is given as "Cisco".
!--- This defines the authentication as open.
speed basic-1.0 basic-2.0 basic-5.5 6.0 9.0 basic-11.0 12.0 18.0 24.0 36.0 48.0 54.0
bridge-group 1 subscriber-loop-control
bridge-group 1 spanning-disabled
bridge-group 1 block-unknown-source
no bridge-group 1 source-learning
no bridge-group 1 unicast-flooding
ip address 192.168.2.1 255.255.255.0
!--- Note: Configure the bridge 1 protocol IEEE and the bridge 1 route IP
!--- before you create interface BVI1 or add the radio interface to bridge group 1.
bridge 1 protocol ieee
bridge 1 route ip
line con 0
line aux 0
line vty 0 4
no scheduler allocate
Use this section to confirm that your configuration works
Output Interpreter Tool
(registered customers only)
(OIT) supports certain
show commands. Use the OIT to view an analysis of
show command output.
Use these commands in order to verify proper DHCP and wireless
show dot11 associations
show ip dhcp binding
The MAC and IP addresses must match in the output of the
show dot11 associations command and the output of
the show ip dhcp binding command. Here is an
1800-ISR#show dot11 associations
802.11 Client Stations on Dot11Radio0:
SSID [Cisco] :
MAC Address IP address Device Name Parent State
0040.96ac.345c 192.168.2.101 CB21AG/PI21AG WLCLIENT self Associated
!--- Output suppressed.
1800-ISR#show ip dhcp binding
Bindings from all pools not associated with VRF:
IP address Client-ID/ Lease expiration Type
192.168.2.101 0100.4096.ac34.5c Dec 18 2005 05:07 PM Automatic
Use this section to troubleshoot your configuration.
Note: Refer to
Information on Debug Commands before you use
Issue the debug ip dhcp server packet
command in order to debug the IP DHCP server. With an unencrypted
open-authentication WLAN, this command provides the quickest and most effective
method to troubleshoot.
The debug ip dhcp server packet command
shows these data transactions:
This output of the debug ip dhcp server
packet command is an example of a successful DHCP request:
1800-ISR#debug ip dhcp server packet
*Dec 17 15:40:50.379: DHCPD: DHCPREQUEST received from client 0100.4096.ac34.5c.
!--- This shows the client DHCP discover packet that is sent to the router.
*Dec 17 15:40:50.379: DHCPD: No default domain to append - abort update
*Dec 17 15:40:50.379: DHCPD: Sending DHCPACK to client 0100.4096.ac34.5c (192.168.2.101)
!--- This shows the router DHCP acknowledgment (ACK) that is sent back to the client.
*Dec 17 15:40:50.379: DHCPD: creating ARP entry (192.168.2.101, 0040.96ac.345c).
*Dec 17 15:40:50.379: DHCPD: unicasting BOOTREPLY to client 0040.96ac.345c (192.168.2.101)
If you do not see the DHCP offer in the output of the
debug ip dhcp server packet command, begin to
troubleshoot the 802.11 protocol. Complete these steps:
Verify the wireless client settings, the SSID, and the no
Note: The SSID must be the same in the ISR and the
clients. In this case, the SSID is "Cisco". Figure 1
and Figure 2 show the SSID settings in both Cisco
Aironet Desktop Utility (ADU) and Aironet Client Utility (ACU). The window that
you see depends on the wireless client card and the firmware versions that you
Figure 1 – Cisco ADU SSID Settings
Figure 2 – Cisco ACU SSID Settings
Figure 3 – Windows Wireless Zero
Verify Wi-Fi compatibility.
Refer to the Wi-Fi
page in order to verify the Wi-Fi compatibility of the wireless
network interface card (NIC) that is used.
Technical Support for further technical assistance.