Automatic detection of digital call paths in a telephone system

Claim 3

The method of claim 1, wherein the maximum data transfer rate of the call is determined based upon the logical state of bits of the second digital probe.

Claim 4

The method of claim 2, wherein the data transfer rate is not greater than the maximum transfer rate indicated by the logical state of bits within the second digital data probe.

Claim 5

The method of claim 3, further including transferring data at the maximum data transfer rate indicated by the logical state of the bits within the second digital data probe.

Claim 6

The method of claim 3, further including transferring data at a data transfer rate that is not greater than the data transfer rate indicated by the logical state of the bits within the second digital data probe.

Claim 7

The method of claim 1, further including the step of deactivating signal processing equipment coupled to the switched telephone network upon transmission of a response by the ATE to initiation of a call by the OTE in order to reduce distortion of digital data communicated between the OTE and ATE.

Claim 8

The method of claim 6, wherein the signal processing equipment includes at least one echo canceler.

Claim 9

The method of claim 6, wherein the signal processing equipment includes at least one echo suppressor.

Claim 10

The method of claim 1, wherein the call is disconnected if the second digital probe is not received within a predetermined period of time.

Claim 11

The method of claim 1, wherein standard analog modulation techniques for establishing the call are attempted before disconnection, if the second digital probe is not received within a predetermined period of time.

Claim 12

The method of claim 1, wherein the selection message selects parameters which govern the transfer of data between the OTE and the ATE over the switched telephone network for the duration of the call.

Claim 13

The method of claim 11, wherein the parameters selected are from among a set of parameters indicated by the state of bits of the second digital probe.

Claim 14

The method of claim 1, wherein the first digital probe comprises the following bit pattern; ______________________________________ Order of Bit Transmission ______________________________________ Order of 0 1 1 1 1 1 1 J sample 1 1 1 1 1 1 1 J transmission 0 1 1 1 1 1 1 J 1 1 1 1 1 1 1 J 0 1 1 1 1 1 1 J 1 1 1 1 1 1 1 J 0 1 1 1 1 1 1 J 1 1 1 1 1 1 1 J 0 1 1 1 1 1 1 J 1 1 1 1 1 1 1 J 0 1 1 1 1 1 1 J 1 1 1 1 1 1 1 J 0 1 1 1 1 1 1 J 1 1 1 1 1 1 1 J 0 1 1 1 1 1 1 J 1 1 1 1 1 1 1 J 0 1 1 1 1 1 1 J 1 1 1 1 1 1 1 J 0 1 1 1 1 1 1 J 1 1 1 1 1 1 1 J 0 1 1 1 1 1 1 J 1 1 1 1 1 1 1 J 0 1 1 1 1 1 1 J 1 1 1 1 1 1 1 J ______________________________________

Claim 15

The method of claim 1, wherein the second digital probe comprises the following bit pattern; ______________________________________ Order of Bit Reception ______________________________________ Order of 1 0 0 X X X X X Sample 1 0 0 X X X X X Reception 0 0 0 X X X X X 0 0 0 X X X X X ______________________________________

Claim 16

The method of claim 1, wherein the second digital probe comprises the following bit pattern; ______________________________________ Order of Bit Reception ______________________________________ Order of X X X 0 X X X X Sample X X X 1 M.sub.0 X X X Reception X X X 1 M.sub.1 X X X . . . X X X 1 M.sub.n X X X X X X 1 P X X X ______________________________________

Claim 17

The method of claim 1, wherein the second digital probe comprises the following bit pattern; ______________________________________ Order of Bit Reception ______________________________________ X X X X X 1 J J ______________________________________

Claim 18

The method of claim 1, wherein the first digital probe includes a first plurality of samples and a second plurality of samples, the least significant bit within each of the first plurality of samples being in a first logic state, and the least significant bit in the second plurality of samples being in a second logic state, such that the least significant bit of at least one of the samples within the first digital probe will be inverted if robbed-bit signaling is used on the call path.

Claim 19

The method of claim 1, further including the step of: a. transmitting samples encoded with digital end user information between the OTE and the ATE upon characterizing the call as digital.

Claim 20

The method of claim 18, wherein the samples encoded with digital end user information are framed as 8-bit samples.

Claim 21

The method of claim 19, wherein: a. only the most significant bit of each 8-bit sample carries a bit of end user information and the second and third most significant bits of each 8-bit sample are set to logic state "0" if 8 kbps operation is selected; b. only the first two most significant bits of each 8-bit sample carry bits of end user information if 16 kbps operation is selected; c. only the first three most significant bits of each 8-bit sample carry bits of end user information if 24 kbps operation is selected; d. only the first four most significant bits of each 8-bit sample carry bits of end user information if 32 kbps operation is selected; e. only the first five most significant bits of each 8-bit sample carry bits of end user information if 40 kbps operation is selected; f. only the first six most significant bits of each 8-bit sample carry bits of end user information if 48 kbps operation is selected; g. only the first seven most significant bits of each 8-bit sample carry bits of end user information if 56 kbps operation is selected; and h. all 8 bits of each 8-bit sample carry bits of end user information if 64 kbps operation is selected.

Claim 22

The method of claim 20, further including the step of: a. transmitting a predetermined number of samples in which each bit of each sample which is capable of carrying end user information is set to a logic "1" and scrambled prior to transmitting samples encoded with end user information.

Claim 23

The method of claim 20, further including the step of: a. transmitting a predetermined number of samples in which each bit of each sample which is capable of carrying end user information is set to a predetermined logic state, prior to transmitting samples encoded with end user information.

Claim 24

The method of claim 20, further comprising the steps of: a. determining whether 56 kbps operation is selected; b. determining whether each of the six most significant bits of a sample are equal to a logic "0" state if 56 kbps operation is selected; c. delaying the transmission of the end user information that would otherwise have been carried by the seventh most significant data bit of the sample; and d. delaying each subsequent bit of end user information by one bit.

Claim 25

The method of claim 20, further comprising the steps of: a. determining whether 64 kbps operation is selected; b. determining whether each of the seven most significant bits of a sample are equal to a logic "0" state if 64 kbps operation is selected; c. setting the eighth most significant bit of a sample to a logic "1" state if 64 kbps operation is selected and each of the seven most significant bits of the sample are equal to a logic "0" state; d. delaying the transmission of the end user information that would otherwise have been carried by the eighth most significant data bit of the sample; and e. delaying each subsequent bit of end user information by one bit.

Claim 28

The method of claim 25, wherein the selection message comprises the following bit pattern; ______________________________________ Order of Bit Transmission ______________________________________ Order of S 0 0 0 X X X X Sample S 0 0 1 M.sub.0 X X X Transmission S 0 0 1 M.sub.1 X X X . . . S 0 0 1 M.sub.n X X X S 0 0 1 P X X X ______________________________________

Claim 31

The method of claim 27, further including the step of: a. transmitting samples encoded with digital end user information between the ATE and the OTE upon characterizing the call as digital and after transmitting the second digital probe.