5G vs VDSL

Silly question, how can a wireless connection (5G) be faster than a physical connection (VDSL) for the last mile?

How? It can be faster by using different technology. VDSL is capped at 80Mbps in the UK and will have a lot of loss on a 1-mile length of copper. Most people are 500metres or less from their local cabinet.

5G is radio, so it will depend how many users there are using the service at the same time.

Why?

The Openreach VDLS (actually VDSL2) has a maximum connection speed of 80Mbps. Even full 4G easily beats that with line of sight of the mast.

5G is far faster than 5G 4G. (Typo fixed, see later post by jchamier ).

Don't be confused by the term "last mile". It is nothing to do with an actual mile. Normally the last leg of the (to<>from) data trip from a concentrator of some kind where multiple signals are routed out as a single connection. Think DSLAM/MSAN/Aggregation point?/Mobile mast.

That's why for instance many more 5G "masts" will be needed than 4G ones to give local car<>car communication for driverless vehicles.

Edited by RobertoS (Fri 14-Feb-20 22:32:58)

For example, I'm ~400m from my cabinet, and get ~76Mbps down. That's on a wired connection. It there was a 5G mast there, I'd probably get gigabit speeds potentially. How is there more loss over a physical wire, than through the air?!

That's the opposite of the question in your OP . You are now asking why a landline is slower than a radio wave. (The Subject can of course be read either way).

They just cannot transmit signals extremely fast and reliably down copper where attenuation is much higher than through air or fibre-optic cable. The capacity is much lower in copper.

Edited by RobertoS (Fri 14-Feb-20 17:31:22)

In reply to a post by jchamier:

How? It can be faster by using different technology. VDSL is capped at 80Mbps in the UK and will have a lot of loss on a 1-mile length of copper. Most people are 500metres or less from their local cabinet.

5G is radio, so it will depend how many users there are using the service at the same time.

Why?

On a side note when Origin operated via Digital Region you could get up to 100mb connection via FTTC (although probably a small proportion).

In reply to a post by RobertoS:

The Openreach VDLS (actually VDSL2) has a maximum connection speed of 80Mbps. Even full 4G easily beats that with line of sight of the mast.

On an early configuration, 2x 20 MHz of bandwidth (FDD) should give 150 Mbps download, and 50 Mbps upload. You can play with this calculator: https://tools.pedroc.co.uk/4g-speed/

5G is far faster than 5G.

Sounds a bit Teresa May! 5G-NR is faster because it has new encoding techniques (e.g. OFDM), and shares the air time in a different way to LTE, which was dramatically different to UMTS of GSM, why the Long Term is the first two letters. Today all 5G NR also needs to be connected to LTE at the same time - this is the Non Stand Alone configuration. I've not yet read of any SA installations.

That's why for instance many more 5G "masts" will be needed than 4G ones to give local car<>car communication for driverless vehicles.

I doubt that use case will ever happen myself, unless cars themselves are transmitters and you're not talking over a traditional cellular network. Many more NR transmitters will be required once we deploy mmWave spectrum, e.g. 60 GHz. I predict there will be little to no indoor penetration.

The UK (ofcom) hasn't yet licensed these frequencies. The US has, and Verizon is building mmWave connectivity in some cities. Note the new Samsung S20 5G does not support mmWave - so buyer beware!

Edited by jchamier (Fri 14-Feb-20 18:22:00)

In reply to a post by AndyPandy:

For example, I'm ~400m from my cabinet, and get ~76Mbps down. That's on a wired connection. It there was a 5G mast there, I'd probably get gigabit speeds potentially. How is there more loss over a physical wire, than through the air?!

That 76Mbps is due to Ofcom/BT limiting to VDSL Profile 17. This was for various reasons including not breaking neighbours still on the old ADSL signal from a far away exchange. Also interference picked up on the wires from heavy industry, or even cars / motorbikes driving past. These wires were not planned for internet access. Other countries have higher profiles and for some people 100 Mbps or faster. G.Fast for example has managed 300 Mbps across the copper wire, but you need to have 100m or less distance. e.g. AT&T U-Verse in parts of America.

With an Ethernet network using Unshielded Twisted Pair most people get 1 Gbps around a home but we are talking 20m to 30m maximum distances between the PC and the switch/router. If you could replace the wire in the street with some shielded coax, (e.g. Virgin Media's cable) then you could achieve 1 Gbps or faster quite easily.

Radio is more complex, if you have a strong signal (from mast to you) and in reverse (you to mast) you can send quite a lot of data quite quickly. However to pay for this you have to share it with other users, this is where 2G(GSM), then 3G(UMTS), then 4G(LTE) and now 5G(NR) are all increasing the total amount of data that is then shared with multiple customers.

I dont see it as VDSL vs 5g I see it as FTTP vs 5g. I am sure FTTP will win out in the long run as the technology develops and 5g becomes over used.

Agreed. Unless there is a constant growth of 5G base stations, in cities a fixed line network should always win. If it’s built properly. A challenge to Virgin Media and OpenReach.