There is no such thing as a typical telephone wiring installation because of factors such as the type of plugs and sockets used (Australian 600-series or modular), the use of parallel or star wiring configurations, the use of DIY extension leads and double-adaptors etc.
Whilst the following diagrams are not comprehensive, they should (in conjunction with a bit of common-sense) assist in helping you to correctly install your ADSL equipment.
The important things to remember are:
The Filter/Splitter (and your ADSL modem) needs to be connected DIRECTLY to the incoming exchange line and must NOT pass through an In-Line Filter first.
All analogue devices/telephones are connected via an In-line Filter.
Scenario 1.
A single telephone near the ADSL modem with no additional telephones in other locations. Either a Filter/Splitter or a Double-adaptor combined with an In-Line Filter is required.
OR
Scenario 2.
A Telephone near the ADSL modem with additional parallel-wired telephones in other locations.
Use a Filter/Splitter plus an In-Line Filter for every telephone.
Scenario 3.
A Telephone near the ADSL modem with additional telephones wired back to a "master" socket in star wiring configuration.
A Central Filter/Splitter is all that is required.
Scenario 4.
A DIY installation using double-adaptors and plug-in extensions cabling from a "master" socket. Double-adaptors, a Filter/Splitter plus In-Line Filters are required.
Scenario 5.
A wireless router installation. A Filter/Splitter plus an In-Line Filter for every telephone is required.
NOTES The ADSL Modem and the Wireless Router can both be replaced by a single Modem/Router. The split configuration as shown is recommended for easy upgradeability. You must have an ethernet compatible printer that will work in conjunction with a wireless router. A standard printer will not work in this configuration. This configuration automatically provides a hardware firewall between your computer and the internet. The laptop must of course be configured to operate on a wireless LAN.