To continually improve service levels, Telecommunication carriers have has an ongoing program to upgrade telephone lines. The vast majority of telephone lines will not require any upgrade work specifically to support an ADSL service. ADSL technology uses a proven robust transmission technique specifically suited to ordinary telephone lines. There are many requirements to be met before an ADSL service can be provided. Not all telephone services belonging to an ADSL covered exchange can necessarily have an ADSL service.
Ethernet is the most popular form of local area networking.
Setting up an Ethernet based LAN for Microsoft Windows is inexpensive and relatively easy. They're a little more expensive than desktop cards. Any connection to the Internet carries some risks. However, DSL provides a dedicated Internet connection over private telephone lines. This reduces the risk of your data being accessed by hackers over a shared network.