WiFi signal jokes

By John Lim, CTO

This old IT man is gonna drop some info on you about wifi and why you have such poor wireless connectivity to your network! Plus I am tossing in the second part of the DNS piece from last month as a bonus. Much Excitement!!!

There are sooooo many things that could contribute to poor wireless connectivity.Besides just signal strength, there are whole swaths of issues like density, frequency saturation, channel interference that we don’t really think about. Typically we just look to see if our wireless device has full bars or not. Let’s talk about things other than signal strength that would typically lead to poor wireless performance.

Super excited right!

Density. When I say density, I am referring to how many wireless devices are connected to your Wireless Access Point(WAP) at the same time. Yes, there is a limit and it is dependent on your WAP. Each WAP is different and handles density very differently. You want to make sure your IT provider is scoping out a wireless solution that fits your requirements. Another thing to consider when it comes to density is MU-MIMO. I know lots of people have heard of 802.11ac and MIMO but have you heard of MU-MIMO? Did you know that prior to MU-MIMO, your WAP could only send data to one wireless device at a time even when “connected” to multiple devices? Sometimes this is referred to as airtime fairness.

Prior to MU-MIMO, a wireless access point when connected to multiple endpoints (laptops, phones, tablets, IoT stuff) would basically act as an air traffic controller designating which of the multiple wireless devices can send data to the WAP one at a time. Obviously, the WAP does this very fast BUT it was still one device at a time. As we all know, everything has wireless network connectivity these days (door bells, dead bolts, speakers, TVs and the list goes on) so to best benefit a wireless dense environment, you should keep MU-MIMO in mind.

Frequency saturation and Channel Utilization.

These two are very much related so we will tackle them together. With respect to wifi, we typically talk about the 2.4GHz and 5GHz spectrums. 2.4GHz is lower frequency so this means lower bandwidth but better penetration compared to the 5GHz spectrum. Do you know that there are really only three Channels on the 2.4GHz spectrum that are non-overlapping channels (1, 6, and 11)? Overlap can create noise on your signal and noise is bad, well pretty much in everything. Depending on how you setup your 5GHz channel width you can have up to 24 non-overlapping channels. Did you know that if your WAP and your neighbor’s WAP are both using the same channel for wifi, you are now crippling each other? Remember our reference to airtime fairness above? Well, if you two have WAPs that are using the same channels, you could possibly cause your end points to wait your turn to transmit data to the WAP even though you have completely separate wireless networks.

YES, this is crazy!

I know, I know, you just want to be connected, and that should be your only concern. Let the RF geeks worry about the rest.


Part Deux of my DNS article

Remember how so long ago we talked about DNS and how we use it for so many things besides just name resolution? Well, we will ONLY talk about name resolution here.

Do you know that there is only ONE department in the world that manages Top Level Domain (TLD) names? TLDs are like .com, .net, .org, etc. The Internet Assigned Numbers Authority (IANA) is a department within the Internet Corporation for Assigned Names and Numbers (ICANN) that manages what are true publicly available TLDs. If you really want to learn more about this – I suggest not – go <here>. Anyways, I mention TLDs because if you have a Microsoft server running Active Directory you are running a mini domain on your private network.

John Lim, CTO
// John, CTO directs our team of technicians in support cases, new project planning, and research and development. John came to TekTegrity after spending ten years as a leader in Cuesta College’s Information Technology Department where he helped make possible Cuesta’s High Tech building, myCuesta portal, and Gmail integration. If you come by the office and there are dozens of donuts, bagels or fresh egg rolls (from San José) in the break room, John is most likely the food fairy who left them. And if he’s not feeding or directing the tech team you might find John having lunch at the Elks Lodge or spot him cruising the coast with his motorcycle gang.  More on John >>