Abstract: A CPE such as an ISDN telephone subset or multimedia equipment includes an interface recognition unit that connects to the network interface and adapts itself to allow the CPE to be used with standard ISDN interfaces and an analog interface. The interface recognition unit includes an interface recognition switch (IRS) that performs two functions. First, the IRS protects the CPE from damage in those instances where a non-standard network interface is connected to the CPE. Second, for standard interfaces, it identifies the type of network interface and routes the incoming signals appropriately. Specifically, if the IRS detects a T interface, the incoming signals are switched directly to a T interface circuit for controlling and powering the higher functions of the CPE. If the IRS detects a U interface, incoming signals are automatically switched to a U interface circuit for controlling and powering the CPE.

Abstract: A CPE such as an ISDN telephone subset or multimedia equipment includes an interface recognition unit that connects to the network interface and adapts itself to allow the CPE to be used with standard ISDN interfaces and an analog interface. The interface recognition unit includes an interface recognition switch (IRS) that performs two functions. First, the IRS protects the CPE from damage in those instances where a non-standard network interface is connected to the CPE. Second, for standard interfaces, it identifies the type of network interface and routes the incoming signals appropriately. Specifically, if the IRS detects a T interface, the incoming signals are switched directly to a T interface circuit for controlling and powering the higher functions of the CPE. If the IRS detects a U interface, incoming signals are automatically switched to a U interface circuit for controlling and powering the CPE.