A simulator system for simulating a wireless local area network in a combination of a wireless local area network and one or more 2G or 3G mobile communication networks includes a first set and a second set of access protocol simulation devices representative of wireless local area network apparatus implementing access protocols. The first set of access protocol simulation devices is representative of radio technology independent apparatus providing integration of the wireless local area network with the mobile communication network(s). The second set of access protocol simulation devices is representative of radio technology dependent apparatus present in the wireless local area network. The simulator is thus configured for simulating different types of wireless local area network technology in the wireless local area network by varying the access protocol simulation devices in the second set while maintaining the access protocol simulating devices in the first set.