Every customer may represent a smartphone and at least one more device (tablet or laptop), which increases their usage when they purchase the product. I analyzed that effect, summarized below:
The average usage is a function of the "headline" or "advertised" data rate and contention ratio.
Contention ratio is greatest at the peak hour.
Contention ratio is greatest at the peak hour.
David Bruner (Panasonic) concurred that they "had provisioned for 150 kbps, but that usage was measured at more like 300 kbps".
When I asked Don Buchman (ViaSat) at Satellite 2016 about this, he confirmed 150 kbps average per user was "in the ball park".
At the end of 2014, ViaSat reported that just 20% of the data traffic is streaming, supporting the point that the average throughput does not represent a large percentage of simultaneous streaming sessions.
ViaSat indicates that 20% percent of all data used is for streaming applications
I have gathered numerous references together that support a service provisioning goal of about 150 kbps per peak user.
http://www.satcom.guru/ Broadband Average Usage is 150 kbps Usage is a combination of traffic to and from the user (forward and return channel). Typical streaming applications favor the forward channel, which creates a lop-sided performance requirement. In general, interactive applications will have a forward:return ration of about 4-8:1 - as measured in aggregate across an large group of users. The trend has been to shift more of the interactive traffic to the return channel, in part due to users wanting to share pictures, movies, and even live streaming.
The average 150 kbps is referring to a composite average data rate to combine forward and return channel usage. Adequate data rate must be provisioned to support the peak number of users in both the forward and return channels. For simplicity one could surmise 120/30 kbps (forward/return) for interactive users and 150/0 kbps for streaming users.
Average Session (120 minutes at 150 kbps)
Typical mobile connectivity is gaged to be 150 kbps per average user. Some users may stream for 30 minutes, while other don't stream at all.
Under-Served Sessions (less than 150 kbps)
An under-served session has a lower average usage, which leads to an average data rate less than 150 kbps. These are sessions where the user does not exercise the session to their best ability, or the session was under-performing due to contention. An average of 50 kbps does not yield a satisfactory Internet access session in any case.
Short Session (less than 120 minutes)
A short session, in this context, is less than 120 minutes. 30, 60, and 90 minutes sessions at an average of 150 kbps are provided, each yield progressively more usage. Low session usage may be a result of a short average session or an under-served longer session.
Heavy Usage Session (more than 150 kbps)
Heavy usage comes from extended streaming sessions, use of higher streaming rates, or excessive Internet access. The average throughput is greater than the average 150 kbps over a 120 minute session.
Future Usage (500 kbps)
In the next five years average mobile Internet sessions will increase to around 500 kbps. Future sessions are expected to support longer streaming durations and higher streaming resolutions. Internet access is similarly expansive in appetite.
Peter Lemme
peter @ satcom.guru
Copyright 2016
All Rights Reserved
Hello, great article! I have a few questions for you:
ReplyDeleteCan you advise what contention ratio has been used?
Wouldnt the contention be a lot greater inflight than on standard cellular networks? i.e. many people in one place over a short period with few other distractions.
The Cisco data consumption numbers you reference for mobile devices are over cellular networks only. Current WiFi/Cellular use for mobile devices is around 80%/20%, so those numbers are only 20% of total data consumption. Do you think the kbps needed should be higher than 150?
Check out this blog to see how 150 kbps is an average for direct to home satellite service, and in other markets.
Deletehttp://www.satcom.guru/2016/02/a-broadband-user-average-throughput-is.html
Frankly the market wants you only to hear the headline rate, so my references are the best I can find in the public domain. I hope that having quotes confirming these rates is helpful.
Contention ratio is scaled against headline rate, so if 12 Mbps headline rate, contention ratio at peak moment is 80:1. Contention is against the satellite network and the local Wi-Fi, but the issue is with the network. There are many distractions inflight.
Thanks Peter, aside from the info from Panasonic/Viasat, you have calculated the 150kbps based on the data consumption figures from Cisco. This would only be 20% of total data consumption from mobiles devices as the rest is "offloaded". Passengers would be using WiFi inflight so behaviours could resemble those on the ground (bandwidth permitting).
DeleteHi Lee,
DeleteThanks for the comment.
I find the Cisco report excludes offload traffic, but they say
"As a percentage of total mobile data traffic from all mobile-connected devices, mobile offload increases from 51 percent (3.9 exabytes/month) in 2015 to 55 percent (38.1 exabytes/month) by 2020 (Figure 19). Without offload, global mobile data traffic would grow at a CAGR of 62 percent instead of 57 percent."
I have another set of excerpts that shows direct to home Internet runs at 150 kbps.
http://www.satcom.guru/2016/02/a-broadband-user-average-throughput-is.html
Taking offload into account, the burden would double to 300 kbps. What is clear is we are on a journey - we have been at 150 kbps and we are going to 929 kbps. The timing is a little fuzzy, but the trends are what I was trying to explore. You may decide that we are further down this road than I.
But the question is are we providing a mobile service or a "home" service. No one is suggesting 4k video streaming, so I think we are a mobile service. Thus, we should fulfill the mobile service levels.
Finally, I harken to my point that Wi-Fi in combination with Airplane Mode is a mobile service that application developers should treat like cellular, not unfettered like home Wi-Fi.
http://www.satcom.guru/2015/08/airplane-mode-2015.html