Binding an FXS voice subscriber line to an FXO voice subscriber line

The one-to-one binding between FXS voice subscriber lines and FXO voice subscriber lines enhances the reliability of voice communication, which is particularly important for some industries. After the binding, FXO voice subscriber lines can be used for communication over PSTN when the IP network is unavailable.

The one-to-one binding between FXS voice subscriber lines and FXO voice subscriber lines provides the following functions:

• Dedicated FXO voice subscriber lines—The FXO voice subscriber lines are used only for the bound FXS voice subscriber lines and PSTN-originated calls received over the FXO voice subscriber lines are directly connected to the bound FXS voice subscriber lines.

• Consistent state between bound FXS and FXO voice subscriber lines—The on-hook/off-hook state of the bound FXS and FXO voice subscriber lines is consistent. If an FXS voice subscriber line receives a PSTN-originated call when the corresponding FXS voice subscriber line goes off-hook, the calling party will hear busy tones.