ADSL is well known as a main technology for home broadband because it runs over regular telephone lines and is widely available. One of the downsides of ADSL is that it is asymmetric, meaning the download speed is much faster than the upload speed. Some offerings are also highly contended leading to erratic performance. It is still widely used on event sites because of its availability and short lead times for installation but it is being replaced by FTTC (Fibre to the Cabinet) and high-speed optic fibre services. As ADSL requires a copper wire connection it can only be activated once a traditional phone line is installed.