Which type of jack should be used to connect an internet communicator?

The RJ-45 jack is the correct choice for connecting an internet communicator because it is specifically designed to accommodate Ethernet networking connections. Ethernet is commonly used for internet communication, and the RJ-45 connector is the most prevalent type used in local area networks (LANs). This connector supports the necessary data transmission required for internet connectivity, allowing devices to communicate effectively over a network.

In contrast, RJ-11 jacks are typically used for telephone connections, making them unsuitable for data communication tasks such as those required by an internet communicator. The RJ-12 jack is essentially a variant of the RJ-11, which is also not meant for Ethernet data transmission. The RJ-31X, while used in some alarm systems, is not the standard for internet connectivity and is more tailored for specific telephone line connections rather than for internet communication.

Therefore, when setting up or troubleshooting a security system that utilizes an internet communicator, using the RJ-45 jack ensures compatibility with Ethernet connections, which is essential for reliable communication and functionality.