A bridge tap is a type of telecommunication connection common in residential neighborhoods, where the telephone company will lay more cables that it needs to add flexibility in the future when the service needs to be assigned and reassigned. While this is convenient for the telecommunications company, it can cause problems for the customer, as bridge taps can come with significant interference, particularly with high-speed data transmissions. Customers who suffer from repeating problems with line interference that cannot be resolved with tactics such as filtering can be helpful in discussing the possibility of a bridged connection with a telephone technician.
When telephone companies lay out lines to establish connections, their goal is to make it easier to provide customer service in the future. They can lay a long section of telephone cable and use tapping bridge, if necessary, to connect various customers to that line, as people enter and leave a community. Historically, multiple people have been connected to a line, in the party line configuration, where families shared a phone number. With multiple lines, the company can provide a complete service to a neighborhood and easily switch lines if needed to adapt to changes.
In a branch configuration, only one family is connected to a given line, but substantial interference can occur. The extra length of the line can generate interference, depending on the length and location of the active phone connection. This can cause problems with services such as Internet service digital subscriber line (DSL), which can be subject to interference. The line can also crackle or pop while people are using the voice connection.
Often, a bridged link is visible. Customers may be able to pinpoint the length of the line and it can be seen that it works continuously beyond the link to their utility pole. On older poles, it is important to pay attention to older lines; when a line breaks, the telephone company can string a new one without removing the old one, in which case a tangle of wires can create an appearance from the ground.
A telecommunications employee can determine if a house has a bridge connection. Physical control can reveal the wiring used in the pole and junction box, and tools for testing the line are also available. Customers with chronic Internet connectivity problems and issues on their voice lines may need to explore a variety of causes before determining what is causing the problem. A telephone technician may suspect a bridged connection after ruling out other common options, and may address the problem by cutting the line, rather than letting him continue beyond the household with a service.