Version 1 was the original version, Version 2 is the more secure version. Version 2 is often referred to as WAP AES because it offers Advanced Encryption Standard (AES)
Both versions a pre-shared key (a password, i.e. PSK) that the client and router know. This does not require and authentication server and is thus often called WPA Personal
WPA Enterprise is often used by larger entities and requires a radius authentication server
Available with both WPA 1 and 2
Client/server model where the client sends an auth request to the radius server with a username and password
Provides greater security and protection against short password dictionary attacks
Various kinds of the Extensible Authentication Protocol (EAP) are used for authentication
A DHCP server runs on the router (e.g. dhcpd), will receive requests from the client, and then dynamically assign an IP address to the requesting machine
To manually get an IP address, you can run dhclient
You can connect to a network through an interface without getting an IP address assigned. Networking utilities are just running dhclient in the background to get this dynamically
Set interfaces up: ip link set <interface> up or ifup <interface> (interface)
Routing table ip route or route
ifconfig -> set interface parameters. iwconfig is this but only for wireless interfaces
/etc/network/interfaces sets default parameters for all the network interfaces. Recall that packets get send to specific interfaces (each interface has its own MAC address and will get assigned its own IP address if connected to a router)
iwlist <interface> scan to scan for wifi networks on a given interface (interface wireless scan)
wpa_supplicant is a lower-level command that handles authentication with a router with WPA security (basically all routers)
e.g. wpa_supplicant -c /etc/wpa_supplicant.conf -i <interface> will attempt to connect to the networks defined in /etc/wpa_supplicant.conf
Can run wpa_passphrase to generate pieces of the config file
Things like the higher-level NetworkManager service and its cli nmcli will handle running wpa_supplicant under the hood, handle automatic connections, reconnecting when a connection drops, etc.
