Arduino/Wi-Fi/setup/Wi-Fi Router Setup
Most wireless routers are set up with password protected security both for wireless devices to use them and to configure them. This is to protect internet connections from hackers and other people accidently using them.
Wifi projects and device testing usually requires an open wifi network. Security is often added later. The objective is then to temporarily setup an open network, do some development and then turn it off when the security is added.
Do not initially attach the WAN port on the back of the router to any institutional network. Most institutions have firewalls that are actively looking for open wifi routers. When found, they will be blocked automatically .. with no human intervention. Security may be notified.
RESET
editWifi routers have passwords to use them and another set of passwords to configure them. Used routers need to be reset back to the factory defaults. Most have a reset button in the back that needs to be held down for 30 seconds while power is on, or held down while the power adapter is plugged into the back of the router. The reset button is often hidden in a deep hole that requires a paper clip pushed into it.
ATTACH WIRED PC
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Configuring the routers often has to be done through a wired connection. The wireless is blocked or perhaps an unknown default wep or wap password is required to access wirelessly. Wireless devices may not be able to configure the router. Plan on attaching a wired PC.
Plug a wired PC into a "LAN" or "Ethernet" port. On the back of the router there are "Internet" or "WAN" ports that may look the same as LAN ports.
Then get into a browser and type 192.168.1.1 or 192.168.2.1 ... a configuration screen should pop up. Each vendors screens will be different. Initially most will ask you for a password.
If this doesn't work, there is a problem with the network card in the PC. Typically the problem is mixing old wifi routers with new PC's.
The user id and passwords could initially be nothing, or some kind of default. In this case both are admin. Some routers the user name is "administrator" with no passwords. Just start trying some combinations.
The default configuration information may be in one screen as is the case with the Linksys or scattered around. Don't worry about the host or domain name. Leave the LAN IP address and subnet mask the same. Leave the SSID enabled. Change the name (linksys in the screen shot) to something that can be remembered like "engineering". The channel should be something that does not conflict with existing wifi networks in the room. Modern wifi routers can automatically pick the unused ones. This router can not. Leave WEP disabled (and WAP and WAP disabled on modern wifi routers). Leave the Internet Connection Type "automatic" or something like that.