1) What is the RGW/Modem/router ( Gateway ) you are using?
2) PC direct to the Gateway using Ethernet cable and make sure it is plugged in ( if its a Laptop) and is on High performance mode. ( quick google search will show 100s of results) if you have a Mac do the same.
3) also check on your task manager on CPU usage. make sure you can see all the CPU cores.
4) Your ethernet Card speed - does it say FE or GE ?
5) speedtest.net and use Vodafone servers and do the speedtest
6) Check CPU usage and checck the speed
7) if you are using wireless to do the speedtest check if you are connected to the 2.4Ghz or 5Ghz
could you get back wit the speeds after that.
Please note that I am not a part of the social media team and help out on my own time where possible.