Some BT customers are unhappy after the company began testing a system that would see broadband customers share IP addresses.
This is due to the fact that the current IPv4 system is running out of space and many internet service providers are not yet ready to switch to the new IPv6 system, PC Pro reports.
BT has been trialling technology called Carrier Grade NAT (CGNAT), which has also been tested by its subsidiary Plusnet.
CGNAT means a single IP address is shared between as many as ten customers. However, it can create several problems for users.
Sharing an IP address means people cannot set up port forwarding on their router, which causes difficulties for anyone hosting a website or online game.
Writing on the BT forums, one user who has been affected by the test commented: "It's causing me a real headache, for a start none of my home servers are now accessible via the web, remote access to my PC is also blocked."
Posted by Mark Wynn