As we all are using more video in our daily lives, I wanted to throw out some technical information that may improve your results. It’s kinda dry, so as not to bury the lead in general:
Enterprise Backbone > 5G Cellular > Wired Ethernet > WiFi > 4G Cellular
(The 5G vs Wire ethernet may or may not be true depending on both the 5G available and the internet available) Also:
Symmetrical technology > Asymmetrical technology
fiber optic > cable
So, why does it matter?
First, video uses A LOT more data than just about anything else we try to move around the internet. I found this interesting website with representations of different amounts of data: http://simplyted.blogspot.com/2005/12/how-to-visualize-data.html
We’ve all heard of bits and byts, and most people familiar with the metric system understand the prefixes kilo, mega, giga, and tera. Just a fun fact that may be too much information: while kilo usually indicate multiples by 1,000 (103), in information technology it more commonly multiples by 1,024 (210). (If you’ve ever purchased a 16GB flash drive and wondered why it only shows 14.8GB available, it’s because marketers and software developers look at things differently).
To further confuse the situation, the root term is a byte: generally 1 character of text. A bit (part of a byte) is a single binary digit and there are 8 bits in a byte making 256 combinations (28). Head spinning yet? Don’t worry, we’re almost there.
One final trick that we need to be aware of is that when we talk about storage (hard drives, flash drives, file sizes, etc.) we are usually talking about bytes (or kilobytes or megabytes, etc.). When we talk about communications, we’re talking about bits – usually bits per second. So, 1 bit per second is really one byte in 8 seconds. When talking about megabits and kilobits versus megabytes and kilobytes, “bits” is usually indicated by lower case “b” and “bytes” is usually indicated by upper case “B”. So, you thought you had a 75MB internet connection? Look again, it’s probably 75Mbs (capital letter indicates using 1024 as the multiplier not 1000, and “b” indicating bits per second, not bytes).
I know, that’s a lot to digest. Take your time, let it sink in, and come back to look at it again sometime. Onward!
Or, Back! to video. The size of this article so far is 2,554 bytes (2.49KB – that’s capital “K”, lower case “B”). (Well, now it’s more, I counted up to the end of the word “is”). That means that it is 20,432 bits, so a really old 9600bps modem would take 2.12 seconds to transmit it. Video, on the other hand, is composed of individual pictures – or frames – about 30 of them per second. Those frames are composed of pixels. Each pixel of a 24-bit image (16 million colors) is, well, 24 bits. If you’re shopped for a new television, you’ve seen specifications like 1080 or 4k resolution. A single frame of a 1080 video is 1920 pixels horizontally and 1080 pixels vertically, or 2,073,600 pixels or 49,766,400 bits – 47.4 Mb (again, little “b” for bits, not bytes). A 9600 bps modem would take almost an hour and a half to transmit that. And that’s just 1/30th of a second of video! Fortunately, geniuses have figured out how to compress things, so 1080 video usually only uses about 5 Mbps. But, you pay for 50 Mbps internet, why do your zoom meetings still look bad? Well, two reasons: Symmetry and sharing.
Sharing is pretty simple, but we might not think of it. If you’re watching Netflix at 1080 resolution and using 5 Mbps, but two kids are in their rooms each doing the same, that’s 15Mbps. If there are 12,000 students on a campus that has a couple 10 Ggigabit backbones… Well, it doesn’t take a lot of figuring to realize they can’t all watch The Walking Dead at the same time. More than that, your home connection to the Internet is likely shared somewhere between your house and Netflix with probably at least one bottleneck between you and whatever service you’re trying to stream from. A garden hose can only fill a swimming pool so fast.
What people might not realize, however, is that WiFi routers have the same limitations – just getting to the local network. Multiple people on the same WiFi network will decrease the available bandwidth for everyone on the [WiFi] network. Weaker signals will also reduce bandwidth as lower speed protocols provide greater range. Not all devices support all WiFi speeds either. Oh, and network bandwidth gets used by ANY network usage, so even if you are watching a movie on your phone that’s stored on your computer (network media sharing) you’re using up WiFi bandwidth.
The final piece of this complex puzzle? Symmetry. Most of our time on the Internet is spent consuming – or downloading. Think in terms of a concert or sports event: There are usually far more people consuming content (watching) than providing content (playing). As a result, many Internet infrastructures have been built based on providing more download capacity than upload. The practice is known as asymmetrical or asynchronous bandwidth. When we stream video or participate in video conferencing, we end up flipping our usage to require more upload bandwidth.
Cable Internet, in particular, is often guilty of providing asymmetrical service – and until recently it didn’t matter. I searched for Comcast (one of Pittsburgh’s regional cable companies) and their upload speeds are typically 10% or less of their download speeds (e.g., 25Mbps down provides 2Mbps up). On the other hand, I have Verizon Fios (fiber optic) Gigabit in my house. Fiber optic services more often provide symmetrical or synchronous bandwidth. In fact, because of other bottlenecks in the system, I typically have HIGHER upload speeds than download.
This is a lot to absorb, but, for the curious, I hope it explains why you get bad video connections. In order to ensure the best experience:
- use a hardwired connection on a symmetrical internet service whenever possible.
- If you have frequent problems, try to manage network use during critical applications
- Each device you use is essentially another person sharing your connection.
- Playing media from your own network devices uses network bandwidth (particularly with WiFi connections)
- Oh, and many smart phones now use your local WiFi to connect (including a phone call) when it’s available.