You are probably referring to frequency that your router operates in, 2.4Ghz and 5.8Ghz. For linksys routers (which i assume should be the same for the Dlinks) you should be able to login and choose which frequency your router operates in, or both. Best method is to leave it at both. Then probably provide the wifi links with two different names. If you have a laptop or any other wireless device capable of 5.8, then it can use that, otherwise you will use the common 2.4Ghz frequency
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You are probably referring to frequency that your router operates in, 2.4Ghz and 5.8Ghz. For linksys routers (which i assume should be the same for the Dlinks) you should be able to login and choose which frequency your router operates in, or both. Best method is to leave it at both. Then probably provide the wifi links with two different names. If you have a laptop or any other wireless device capable of 5.8, then it can use that, otherwise you will use the common 2.4Ghz frequency