Protected muldem with independent protective switching of circuits having different data rates

A multiplexer combining a plurality of parallel data paths carrying different data rates LS and IS, where IS is greater than LS, for serial transmission of data at a yet higher rate HS, comprising:

• N data input lines;
• a plurality of parallel data input groups for each said line;
• a plurality of parallel data input channels for each said group;
• each said group receiving either LS rate data in parallel form through said channels or IS rate data in serial form;
• normally on-line LS transmit means for each group which receives LS rate data, said LS transmit means multiplexing said LS rate data on said channels and serially transmitting IS rate data on its respective group;
• normally on-line IS transmit means for each group which receives IS rate data, said IS transmit means serially receiving and transmitting IS rate data on its respective group;
• N normally on-line HS transmit means, each multiplexing parallel IS rate data from a respective plurality of said groups and serially transmitting HS rate data;
• N data output lines, each serially carrying HS rate data from a respective HS transmit means;
• standby LS transmit means having an input in parallel with said plurality of parallel data input groups of each said N data input lines;
• standby IS transmit means having an input in parallel with said plurality of parallel data input groups of each of said N data input lines;
• standby HS transmit means having an output in parallel with the outputs of said N normally on-line HS transmit means;
• interconnection means connecting the outputs of said normally on-line LS and IS transmit means in said plurality of groups for each said line to the respective normally on-line HS transmit means and to said standby HS transmit means, and connecting said standby LS and standby IS transmit means to each of said N normally on-line HS transmit means and to said standby HS transmit means, providing standby data path protective switching means for both said normally on-line LS and IS transmit means, and providing independent protective switching of said normally on-line LS, IS and HS transmit means;
• and
• monitor means sequentially testing data paths through said multiplexer and comprising monitor connections to said plurality of parallel data input groups for each of said N input lines and comprising monitor connections to the outputs of each of said N normally on-line HS transmit means and said standby HS transmit means, said monitor means testing a selected path identified according to an associated HS line designation, data group designation and channel designation, said monitor establishing a sequence of testing in which the line designation is changed more frequently than the group designation, thereby minimizing the time to detect a failure in one of said HS transmitter means.

A high reliability digital demultiplexer comprising in combination:

• a plurality of parallel data output groups;
• normally on-line high speed data receiver means demultiplexing serial high speed data for parallel transmission over said groups;
• a plurality of normally on-line group receiver means, one for each group, receiving parallel identical rate data from said high speed receiver means and transmitting data over said output groups;
• normally off-line standby group receiver means having a parallel output with said plurality of parallel data output groups for protective bypass switching around any of said normally on-line group receiver means;
• normally off-line standby high speed data receiver means having a parallel input with said normally on-line high speed data receiver means for protective bypass switching therearound;
• interconnection means capable of connecting the output of said normally on-line high speed data receiver means to the inputs of said plurality of normally on-line group receiver means and to the input of said standby group receiver means and capable of connecting the output of said standby group receiver means to the inputs of said plurality of normally on-line group receiver means and to the input of said standby group receiver means;
• and
• means for comparing output data selected from said data output groups with corresponding data selected from one of said high speed data receiver means to detect errors;
• means, interacting with said comparing means, for determining when said errors probably result from operation of an identified one of said group receiver means;
• and
• means, responsive to said determining and cooperating with said interconnection means, for switching data through the standby group receiver means to bypass the identified means, independent of switching between said normally on-line and standby high speed data receiver means.

A demultiplexer delivering a plurality of parallel data paths carrying different data rates LS and IS, where IS is greater than LS, from a serial input of data at a yet higher rate HS, comprising:

• N data output lines;
• a plurality of parallel data output groups for each said output line;
• a plurality of parallel data output channels for each said group;
• each said group delivering either LS rate data in parallel form through said channels or IS rate data in serial form;
• normally on-line LS receiver means for each group which delivers LS rate data, said LS receiver means demultiplexing serial IS rate data for parallel delivery of LS rate data on said channels of its respective group;
• normally on-line IS receiver means for each group which delivers IS rate data, said IS receiver means serially receiving and delivering IS rate data on its respective group;
• N normally on-line HS receiver means, each demultiplexing serial HS rate data for parallel transmission of IS rate data to a respective plurality of said groups;
• N data input lines each serially carrying HS rate data to a respective HS receiver means;
• standby LS receiver means having an output in parallel with said plurality of parallel data output groups of each of said N data output lines;
• standby IS receiver means having an output in parallel with said plurality of parallel data output groups of each of said N data output lines;
• standby HS receiver means having an input in parallel with the inputs to said N normally on-line HS receiver means;
• interconnection means connecting the output of each of said N normally on-line HS receiver means to said normally on-line LS and IS receiver means in said plurality of groups for each respective said line and to said standby LS and IS receiver means, and connecting the output of said standby HS receiver means to said normally on-line LS and IS receiver means in said plurality of groups in each of said lines and to said standby LS and IS receiver means, providing standby data path protective switching means for both said normally on-line LS and said IS receiver means, and providing independent protective switching of said normally on-line LS, IS and HS receiver means;
• and
• monitor means sequentially testing data paths through said demultiplexer and comprising monitor connections to said plurality of parallel data output groups for each of said N data output lines and comprising monitor connections to the inputs of each of said N normally on-line HS receiver means and said standby HS receiver means, said monitor means testing a selected path identified according to an associated HS line designation, data group designation and channel designation, said monitor establishing a sequency of testing in which the line designation is changed more frequently than the group designation, thereby minimizing the time to detect a failure in one of said H/s receiver means.

A high reliability digital muldem comprising in combination:

• a plurality of parallel data input transmission groups;
• normally on-line high speed data transmitter means multiplexing said transmission groups for high speed serial data transmission;
• a plurality of parallel data output reception groups;
• normally on-line high speed data receiver means demultiplexing serial high speed data for parallel transmission over said reception groups;
• a plurality of normally on-line group transmitter means, one for each said transmission group, receiving input data on a respective said transmission group and transmitting identical rate data to said high speed data transmitter means;
• a plurality of normally on-line group receiver means, one for each said reception group, receiving identical rate data from said high speed data receiver means and transmitting output data on a respective said reception group;
• normally off-line standby group transmitter means having a parallel input with said plurality of said parallel transmission groups for protective bypass switching around any of said normally on-line group transmitter means;
• normally off-line standby group receiver means having a parallel output with said plurality of parallel reception groups for protective bypass switching around any of said normally on-line group receiver means;
• normally off-line standby high speed data transmitter means having a parallel output with said normally on-line high speed data transmitter means for protective bypass switching therearound;
• normally off-line standby high speed data receiver means having a parallel input with said normally on-line high speed data receiver means for protective bypass switching therearound;
• interconnection means capable of connecting the outputs of said plurality of normally on-line group transmitter means to either of said high speed data transmitter means, and capable of connecting the output of said standby group transmitter means to either of said high speed data transmitter means;
• second interconnection means capable of connecting the output of said normally on-line high speed data receiver means to said plurality of normally on-line group receiver means and to said standby group receiver means, and capable of connecting the output of said standby high speed data receiver means to said plurality of normally on-line group receiver means and to said standby group receiver means;
• and
• means for comparing data selected from said data groups with corresponding data selected from one of said high speed means to detect errors;
• means, interacting with said comparing means, for determining when said errors probably result from operation of an identified one of said group means;
• and
• means, responsive to said determining cooperating with both said interconnection means, for switching data through the standby group means to bypass the identified means, independent of switching between said normally on-line and standby high speed means.

A muldem combining a plurality of parallel data paths carrying different data rates LS and IS, where IS is greater than LS, for serial transmission of data at a yet higher rate HS, and delivering a plurality of parallel data paths carrying different data rates LS and IS from a serial data rate HS, comprising:

• N data input transmission lines;
• N data output reception lines;
• a plurality of parallel data input transmission groups for each said input transmission line;
• a plurality of parallel data output reception groups for each said output reception line;
• a plurality of parallel data input transmission channels for each said transmission group;
• a plurality of parallel data output reception channels for each said reception group;
• each said transmission group receiving either LS rate data in parallel form through said transmission channels or IS rate data in serial form;
• each said reception group transmitting either LS rate data in parallel form through said reception channels or IS rate data in serial form;
• normally on-line LS transmit means for each transmission group which receives LS rate data, said LS transmit means multiplexing said LS rate data on said transmission channels and serially transmitting IS rate data on its respective transmission group;
• normally on-line LS receiver means for each reception group which transmits LS rate data, said LS receiver means demultiplexing IS rate data on its respective reception group and serially transmitting LS rate data on said reception channels in the respective reception group;
• normally on-line IS transmit means for each transmission group which receives IS rate data, said IS transmit means serially receiving and transmitting IS rate data on its respective transmission group;
• normally on-line IS receiver means for each reception group which transmits IS rate data, said IS receiver means serially receiving and transmitting IS rate data on its respective reception group;
• N normally on-line HS transmit means, each multiplexing parallel IS rate data from a respective plurality of said transmission groups and serially transmitting HS rate data;
• N normally on-line HS receiver means, each demultiplexing serial HS rate data for parallel transmission of IS rate data to a respective plurality of said reception groups;
• N data output transmission lines, each serially carrying HS rate data from a respective HS transmit means;
• N data input reception lines, each serially carrying HS rate data to a respective HS receiver means;
• standby LS transmit means having an input in parallel with said plurality of parallel data input transmission groups of each of said N data input transmission lines;
• standby LS receiver means having an output in parallel with said plurality of parallel data output reception groups of each of said N data output reception lines;
• standby IS transmit means having an input in parallel with said plurality of parallel data input transmission groups of each of said N data input transmission lines;
• standby IS receiver means having an output in parallel with said plurality of parallel data output reception groups of each of said N data output reception lines;
• standby HS transmit means having an output in parallel with the outputs of said N normally on-line HS data transmit means;
• standby HS receiver means having an input in parallel with the inputs to said N normally on-line HS data receiver means;
• first interconnection means connecting the outputs of said normally on-line LS and IS transmit means in said plurality of transmission groups for each said transmission line to the respective normally on-line HS transmit means and to said standby HS transmit means, and connecting said standby LS and standby IS transmit means to each of said N normally on-line HS transmit means and to said standby HS transmit means, and second interconnection means connecting the output of each of said N normally on-line HS receiver means to said normally on-line LS and IS receiver means of said plurality of reception groups for its respective reception line and to said standby LS and IS receiver means, and connecting said standby HS receiver means to said normally on-line LS and IS receiver means in said plurality of reception groups in each of said N reception lines and to said standby LS and IS receiver means, providing standby data path protective switching means for both said normally on-line LS and IS transmit means and for both said normally on-line LS and IS receiver means, and providing independent protective switching of said normally on-line LS, IS and HS transmit and receiver means;
• and
• monitor means sequentially testing data paths through said muldem and comprising monitor connections to said plurality of parallel data input transmission groups for each of said N data input transmission lines, to said plurality of parallel data output reception groups for each of said N data output reception lines, to the outputs of each of said N normally on-line HS transmit means and said standby HS transmit means, and to the inputs of each of said N normally on-line HS receiver means and said standby HS receiver means, said monitor means testing a selected path with a tested path being identified according to an associated HS line designation, data group designation and channel designation, said monitor establishing a sequency of testing in which the line designation is changed more frequently than the group designation, thereby minimizing the time to detect a failure in one of said HS transmitter or receiver means.