Dhcp assignment through ethernet bridge

Unanswered Question
Apr 17th, 2007


I've a Cisco WLC 4402, 16 AP(1000 series, 1120 series 1130 series), 6 WLANS, 30 Clients. All works fine but I've a little problem with DHCP assignment: if I connect a notebook through its wireless network card I can retrieve an IP address and all is ok. If I connect the notebook through an Ethernet Bridge (like Linksys Ethernet Bridge WET54G V 3.1) I must assign a static Ip to my notebook to have connectivity.

Note that Ethernet Bridge use the same credentials used on notebook wireless card and the bridge is able to obtain a dynamic Ip from WLC.

Why the notebook can't retrieve a Ip address if it is connected through an Ethernet bridge?

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
scottmac Tue, 04/17/2007 - 06:18

Check your bridge for some flavor of broadcast control.

The initial DHCP request is broadcast; if your bridge is filtering broadacasts (more like a router than a bridge), the DHCP request never makes it to the newtwork.

If you run Ethereal / Wireshark on the client and capture the session, you should be able to determine where in the DHCP process is breaking down.

Good Luck


csannedhi Tue, 04/17/2007 - 09:38

Keep in mind that the Linksys bridge itself won't get a dynamic IP, it merely acts like a passthrough so that your notebook will receive an IP from the network. Log into Web UI and check the operation mode, it should be set to Infrastructure mode. Also verify security settings.

vochiquycmc Sat, 05/19/2007 - 15:37

hi abettiato,

i have 1 WLAN 4402, 1 wireless controller 2710, and about 12 access point 1242.

what should i must config on WLan 4402, on controller 2710, and on AP 1242.

can you send me some documents step by step?

thank you very much!!


This Discussion



Trending Topics: Other Wireless Mobility

client could not be authenticated
Network Analysis Module (NAM) Products
Cisco 6500 nam
reason 440 driver failure
Cisco password cracker
Cisco Wireless mode