Access Points –TpLink WR841N — a Good Price Performer

$20 from Amazon

$20 from Amazon

This Access Point was installed in Haiti in a number of schools. In preparation, the device was analyzed by Richard Smith, a long time hardware engineer at OLPC Boston.  He determined that the device would survive reverse polarity power connections, and remarked that for the $20 price, the unit seemed to be pretty well designed.

It comes with a 9.5v power adapter, but appears to work adequately over the 8-15v range (the upper limit for charging lead acid batteries is about 15v.  So it seems like a good candidate for being run on battery power, and for being the end point of Power Over Internet (POE) in situations where the AP needs to be closer to the clients (sometimes the rebar in cement construction keeps the wifi signal from going from the first floor to the second, etc).

When you first turn the Tp-Link on, it will assign itself the 192.168.0.1 address. When you connect an ethernet cable to your laptop, and browse to this address, you should get a authentication request. Type in username “admin” and password “admin”, in order to get access.

Disable DHCP

Disable DHCP

To work properly in a school server environment, the DHCP (dynamic host config protocol) server must be turned off (the school server does this itself). The image at left shows the “radio button” (round check box) that must be disabled.

Then the ip address of the AP itself must be moved to a location where the school server, and all of the clients can have access.  Change the ip address of the AP LAN to 172.18.126.101 (if more than one AP is present in the system use 102, 103,

Configured for School Server

Configured for School Server Environment

104,. . .). The netmask drop down must be selected, then other netmasks, and the appropriate mask for the school server system entered — “255.255.224.0”.  When you click on save, the AP will reboot, and you will need to enter the new address, 172.18.126.101, in the browser address bar.

Lastly, you will need to set the name of the AP to something that makes sense for your deployment.  Usually, in Haiti, it has be set to the creole word for “school”.

AP name is also called the SSID

AP name is also called the SSID

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