In setting up a wireless network with a wireless broadband router, do you need to disconnect the firewalls in order for computers on the same SSID to be able to access each other? Can you run two different wireless networks, one that allows the other laptops to access the Internet, and an ad hoc network for a WLAN?
Most wireless broadband routers do not filter traffic exchanged between stations on the same wired or wireless LAN. Instead, firewall filters are applied to traffic flowing between the LAN and the WAN (Internet). Therefore, two stations using the same SSID to access the same infrastructure mode WLAN can usually communicate with each other by relaying LAN frames through the wireless broadband router.
Some APs do support multiple SSIDs by using a single radio tuned to one channel. However, if a device only has one radio, it cannot operate in both infrastructure mode and ad hoc mode at the same time. Therefore, your laptop can either connect to SSID#1 in infrastructure mode to reach the Internet through your wireless router, OR it can connect to SSID#2 in ad hoc mode to directly reach another station, but it cannot do both simultaneously unless it has two wireless PC cards.
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