# US 5,353,327 A · Maintenance termination unit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,353,327 A - Document ID: US5353327A - Status: Granted - Kind: A - Application number: 07/878,376 - Filed: 1992-05-04 - Granted: 1994-10-04 - Earliest claimed: 1992-05-04 - Assignees: AT&T Bell Laboratories - Inventors: Seva nanda Adari; Marilyn C. Chiang; Anthony M. DeSanto; R. Earl Fenley, Jr.; Anand K. Javvaji; Ramadevi Sreedhara - Web page: https://patentgrep.com/patent/US5353327A ## CPC - H04M 3/30: for subscriber's lines {, for the local loop} - H04M 3/301: {Circuit arrangements at the subscriber's side of the line} - H04M: TELEPHONIC COMMUNICATION (circuits for controlling other apparatus via a telephone cable and not involving telephone switching apparatus G08) ## Abstract An "intelligent" maintenance termination unit (MTU) that can be installed at or near the demarcation point between the telecommunications network and Customer Premises Equipment (CPE), includes a program controlled processor arranged to perform numerous testing and evaluation functions on (1) the CPE and the drop portion of the telecommunications circuit located on the customer side of the MTU, as well as (2) the line portion of the telecommunications circuit on the network side of the MTU. Testing may be initiated in response to actuation of a pushbutton switch or other initiation means by the customer. Specific tests are then performed in response to receipt of signal sequences (such as Touch-Tone signals) received from a technician at a remote test center. The MTU advantageously includes audio input (microphone) and output (speaker) units, preferably in the form of a speakerphone set, enabling the technician to be placed in direct audio communication, in real time, with the customer when the MTU is actuated. The MTU is transparent to normal line operation, i.e., ringing, dialing and routine maintenance otherwise performed from the central office or by the CPE. ## Claims ### Claim 1 Telecommunications testing apparatus for use in testing a communications line connecting Customer Premises Equipment (CPE) to a telecommunications network, said telecommunications testing apparatus comprising means for establishing a voice communication path between a customer using said telecommunications testing apparatus and a technician remotely performing tests on said telecommunications network and said CPE, said path including said communications line, and means enabling said customer and said technician to cooperatively perform a series of tests on said communications line using information provided via said voice communication path, said tests being arranged to isolate troubles as being in either said telecommunications network or said CPE. ### Claim 2 (depends on 1) The invention defined in claim 1 wherein said last mentioned means includes means for opening the connection between said telecommunications network and said CPE. ### Claim 3 (depends on 1) The invention defined in claim 1 wherein said last mentioned means includes a microprocessor arranged to perform a plurality of measurements in response to remotely generated signal sequences received from said technician. ### Claim 4 (depends on 2) The invention defined in claim 2 wherein said tests are selected from the group consisting of: continuity, noise measurement, two-way loss measurement, and CPE supervision and tranmission tests. ### Claim 5 (depends on 2) The invention defined in claim 2 wherein said tests include line side tests which test the performance of said communications line and CPE side tests which test the performance of said CPE. ### Claim 6 (depends on 1) The invention defined in claim 1 wherein said telecommunications testing apparatus further includes means for initiating said initiating of tests, said means being actuatable only locally by a user of said apparatus. ### Claim 7 (depends on 1) The invention defined in claim 1 wherein said telecommunications testing apparatus includes a visual display indicating the results of the tests and the status of said apparatus. ### Claim 8 (depends on 1) The invention defined in claim 1 wherein said telecommunications testing apparatus includes an oscillator arranged to generate a test signal of known frequency and signal strength. ### Claim 9 (depends on 8) The invention defined in claim 8 wherein said telecommunicating testing apparatus further includes a tone detector arranged to recognize the presence of signals having a preselected frequency. ### Claim 10 (depends on 3) The invention defined in claim 3 wherein said signal sequences are sequences of Touch-Tone digits. ### Claim 11 Telecommunications testing apparatus for use near the demarcation point between a telecommunications network and Customer Premises Equipment (CPE) connected to said telecommunications network, said apparatus comprising means responsive to receipt of Touch-Tone sequences generated in a remote test center for performing a series of performance measurements on said CPE and said network, wherein for at least some of said measurements, said apparatus is arranged to isolate said CPE from said network, and means for establishing audio communication between a user of said testing apparatus and said remote testing center, whereby ones of said performance measurements can be performed cooperatively by a person in said test center and said user. ### Claim 12 A Maintenance Termination Unit (MTU) arranged to perform tests on Customer Premises Equipment (CPE) connected to a telecommunications network to isolate problems as being in said CPE or in said network, said MTU including a microprocessor arranged to perform a sequence of tests under the control of a technician, means in said MTU operable to isolate said CPE from said network, and means in said MTU for establishing two way audio communication between said technician and a user of said MTU during performance of at least a portion of said test sequence. ### Claim 13 Apparatus for performing remote testing on Customer Premises Equipment (CPE) connected to a telecommunications network, said apparatus being connected near the point of demarcation between said network and said apparatus, said apparatus comprising a processor for controlling the performance of a test sequence, a plurality of switches actuatable by a user to control said processor, and a speakerphone allowing audio communication with said user during said testing, wherein said apparatus is arranged to derive operating power for said processor and said speakerphone from said telecommunications network. ### Claim 14 A method for testing a telecommunications system including a telecommunications network and Customer Premises Equipment (CPE) connected to said telecommunications network, said method comprising the steps of isolating said CPE from said network and performing a series of performance measurements on said CPE and said network, both in response to receipt via a communications path of Touch-Tone sequences generated in a remote test center, and establishing audio communication via said communications path between a user of said testing apparatus and said remote testing center, whereby ones of said performance measurements are performed cooperatively by a person in said test center and said user. ### Claim 15 A method of testing a communications line connecting Customer Premises Equipment (CPE) to a telecommunications network, said method comprising the steps of installing test apparatus in said communications line near the demarcation point between said network and said CPE; establishing a voice communication path in said communications line between a customer using said test apparatus and a technician remotely performing tests on said telecommunications network and said CPE; and performing a series of tests by cooperation between said customer and said technician using information provided via said voice communication path, at least one of said tests including the step of activating said test apparatus to isolate troubles to either said telecommunications network or said CPE. ### Claim 16 (depends on 15) The method defined in claim 15 wherein said last mentioned step includes opening the connection between said telecommunications network and said CPE. ### Claim 17 (depends on 15) The method defined in claim 15 wherein said last mentioned step includes performing, under microprocessor control, a plurality of measurements in response to remotely generated signal sequences received from said technician. ### Claim 18 (depends on 16) The method defined in claim 16 wherein said tests are selected from the group consisting of: continuity, noise measurement, two-way loss measurement and CPE supervision and transmission tests. ### Claim 19 (depends on 16) The method defined in claim 16 wherein said tests include line side tests which test the performance of said communications line and CPE side tests which test the performance of said CPE. ### Claim 20 (depends on 15) The method defined in claim 15 wherein said method includes the step of initiating said series of tests only upon local actuation of initiating means in said test apparatus. ### Claim 21 (depends on 15) The method defined in claim 15 wherein said method further includes indicating the results of the tests and the status of said test apparatus on a visual display. ### Claim 22 (depends on 15) The method defined in claim 15 wherein said method further includes generating test signals using an oscillator. ### Claim 23 (depends on 22) The method defined in claim 22 wherein said method further includes detecting supervision of said CPE using a drop current sensor. ### Claim 24 (depends on 17) The method defined in claim 17 wherein said signal sequences are sequences of Touch-Tone digits. ### Claim 25 A method for testing a telecommunications system including a telecommunications network and Customer Premises Equipment (CPE) connected to said telecommunications network, said method comprising the steps of receiving Touch-Tone sequences generated in a remote test center; responsive to said Touch-Tone sequences, performing a series of performance measurements on said CPE and said network, at least some of said measurements including isolating said CPE from said network; and establishing audio communication between a user of said testing apparatus and said remote testing center, whereby ones of said performance measurements are performed cooperatively by a person in said test center and said user. ### Claim 26 Telecommunications testing apparatus for use near the demarcation point between a telecommunications network and Customer Premises Equipment (CPE) connected to said telecommunications network, said apparatus comprising means operative to isolate said CPE from said network only in response to local actuation by a user of said testing apparatus, means responsive to receipt of Touch-Tone sequences generated in a remote test center for performing a series of performance measurements on said CPE and said network, and means for deriving power to operate said testing apparatus from said telecommunications network.