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my Vodafone router connect to the exchange at 72mbps but all speed tests I run at various times of the day and night and from various devices (cabled and wireless) report that my speed never goes higher than 64/65 mbps. if I connect ay 72mbps means the network is capable to provide me with that speed most of the time. Do you or Openreach throttle me? Do you or Openreach cap my speed, please? Where are the missing mbps gone, please? With Virgin I never had this issue, I was getting all mbps at any time
Okay, so saying the sync rate is 72Mbps is misleading to start, you have to consider that number as a symbol rate and not a bit rate, so by the time you've taken the overhead from error correction and protocols, you can certainly knock off a couple of Mbps from that figure.
Then you have to consider how you are connecting to the modem/router. If you are doing that via WiFi you have more overhead on the connection, and if that connection is on the 2.4GHz band you aren't going to have that much overhead on the VF router anyhow.
The only way you could REALLY test the download rate is to connect a computer to directly to a dedicated modem via a cable and then run the speed tests!
Oh, and just for info, what's your actual guaranteed download speed!