Netgear Trek N300 question: Wireless Networking Broadcast

Hi everyone,

I bought a Netgear Trek N300 series router for travel purposes, and sometimes I use it while I am at the house. Yesterday, I was using the Network Genie software to determine why my speed was slow, and I noticed there were 7- 8 network devices that had different IP addresses; sometimes it varied between 6-7 network devices. I'm assuming that my wifi router is broadcasting, and i only want it to broadcast to two devices that are mine. So how do i limit the amount of devices that are connected to it? I only had two network devices that were connected to the router, and i do have a few other network devices, but i did not connect them to the wireless router.   Until then I think i will limit using the router until i feel that it is secured.  Assistance is appreciated.

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