Does a higher broadband speed over 35MG improve the picture quality on Sky Glass?

[BHS1952]

Just wondered if upping my broad speed above 35MB would increase the quality of my Sky Glass picture.

Many thanks in advance.

[mikealanr]

Hi @BHS1952 

Sky recommend 10Mbps for HD and 25Mbps for UHD. This is for each glass device. Any other device in your network (phones, tablets laptops etc) will all be competing for bandwidth.

Streaming services use "adaptive bitrate" meaning it adapts the picture quality to the available bandwidth.

You would likely have a far better Glass experience with increased internet speed.

MikeAlanR

[Chrisee]

@mikealanr short answer no. A stream does burst above the average is around saY 20Mb/s but assuming you have enough hreadroom to cope with that it cannot add quality. It is thecreason why the units only have 100Mb/s ethernet ports is not a problem. 

[mikealanr]

@Chrisee I get what you are saying, but with very limited headroom the OP has they could (and likely to be) be experiencing degradation in adaptive streams. It would be particularly noticeable on something like Netflix or 4od. 

Increasing that headroom would lead to greater stability and result in full rates being available, particularly if more than one Glass device is being used. The headroom from 25Mbps to 35 and to 100 isn't really comparable?

I didn't say it would lead to better quality but a better Glass experience, and my assertion still stands.

MikeAlanR

[Chrisee]

@mikealanr have to agree to disagree video streaming does not require much extra bandwidth what is more important is low jitter.

[BHS1952]

Many thanks

Very helpful

[BHS1952]

Could you explain 'low jitter'.

Thanks

[Chrisee]

@BHS1952 jitter is the measure of regulatrity of the data stream. The data required for a video stream is delivered in data packets pretty obviously these have to be received in order so the stream can be re-assembled. Where a packet is missing or arrives out of order that disrupts the process of assembling the stream for display. There is a limited buffer built into the system but where that is exceeded the stream is disrupted with stuttering, macro blocking etc and if limits are exceeded loss of the stream. 

The biggest source of jitter is the wifi signal in your home which is liable to interference from other wifi networks but also from a range of other sources. Having excess bandwidth within a home network is far more important than faster external connection in my opinion. 

We are talking about digital data where if 100% of what is sent is received then the stream plays at the quality intended. The average data rate for UHD is around 20Mb/s but can rise and fall which is why 25Mb/s is recommended but many people including myself go for a belt and braces 35Mb/s. That rate is determined by the level of  compression at the headend that is something out of your control. Having 100Mb/s available isnt going to change the compression so as long as your connection can handle any peak bursts then having excess bandwidth is not going to improve quality.

In a trial I streamed 2 Sky Sports UHD events and 2 HD streams over my 80Mb/s FTTC connection all of ehich played wiithout issue and had around 20Mb/s capacity left for other network devices to access.. 

[BHS1952]

Thank you so much for your I formed response.