I teach netacad at the HS level & we have several 4221s. About 4 have started asking for username & password, even when not configured with them. I have tried using rommon to switch registries, but still popping up with the request. We got into one w...

have a question that might not be well-formed.In wireless communication, the 2.4 GHz and 5 GHz frequencies are well-known. In the 2.4 GHz band, there are three non-overlapping channels: 1, 6, and 11, which are spaced 5 channels apart. In the 5 GHz ba...