9wi-fi, based on app-based wifi marketing. With the rapid development of "mobile internet" and "connection of things", wifi as a basic service will play an especially important role as a bridge, and it is clear that "wifi routers" will form an integral part of the construction of indispensable facilities. The manner in which the software and hardware (wifi routers + mobile app) of the mini-wifi routers have been achieved can undoubtedly be of great help to the rapid development of both. Users of the working principles of the 9wifi router entered the area where the 9wifi router was deployed: the mobile terminals that had been installed with the 9wifi router did not need account codes to go directly online. At present, many public places are covered by wifi using home routers, home routers with good surface coverage signals and, in practice, limited access to the internet and limited coverage distances. In public places, the construction of base stations using the engineering router + engineering ap+ station + orientation antenna model is necessary to truly meet the needs of hundreds of people, thousands of people with internet access, and the coverage is wide. Description of equipment: 1. Engineering routers: support for 100-person network connections, distribution of internet access ip. Project ap; ap is equivalent to a bridge linking the wireless and wireless networks, whose main function is to connect the various wireless network clients together and then connect the wireless network to the ethernet