Interfacing 622.08 MHz line interface to a 77.76 MHz SONET framer
View Patent ↗A line card for use in a node of a network to connect to optical network lines is provided. The line card includes an optical interface, and a serializer/deserializer (SERDES) operating at a first frequency. The line card also includes a framer operating at a second frequency where the first frequency is higher than the second frequency. The framer includes a digital step up converter to receive data from the SERDES and a digital step down converter to supply data to the SERDES. The step down converter includes a set of input buffers where each input buffer receives a word of nibbles from the framer. The input buffers are loaded one after another, but extraction from each of the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved. The step up converter includes a set of input buffers and a register array where each input buffer receives a word of nibbles from the register array. The input buffers are loaded one after another, but extraction from the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved.
1. A line card for use in a node of a network to connect to optical network lines, comprising:
an optical interface;
a serializer/deserializer (SERDES) configured to operate at a first frequency; and
a framer configured to operate at a second frequency, the first frequency being higher than the second frequency, the framer including a digital step up converter to receive data from the SERDES and a digital step down converter to supply data to the SERDES;
wherein the step down converter includes a set of input buffers, each input buffer configured to receive a word of nibbles from the framer, the input buffers being loaded one after another, but extraction from each of the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved;
wherein the step up converter includes a set of input buffers and a register array, each input buffer configured to receive a word of nibbles from the register array, the input buffers being loaded one after another, but extraction from the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved, and wherein the set of input buffers of the step up converter includes 4 input buffers and the set of input buffers of the step down converter includes 4 input buffers;
wherein the multi-stage multiplexer of the step down converter is a 5 stage converter.
2. A line card for use in a node of a network to connect to optical network lines, comprising:
an optical interface;
a serializer/deserializer (SERDES) configured to operate at a first frequency; and
a framer configured to operate at a second frequency, the first frequency being higher than the second frequency, the framer including a digital step up converter to receive data from the SERDES and a digital step down converter to supply data to the SERDES;
wherein the step down converter includes a set of input buffers, each input buffer configured to receive a word of nibbles from the framer, the input buffers being loaded one after another, but extraction front each of the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved;
wherein the step up converter includes a set of input buffers and a register array, each input buffer configured to receive a word of nibbles from the register array, the input buffers being loaded one after another, but extraction from the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved, and wherein the set of input buffers of the step up converter includes 4 input buffers and the set of input buffers of the step down converter includes 4 input buffers;
wherein the multi-stage multiplexer of the step up converter is a 2 stage converter.
3. A line card for use in a node of a network to connect to optical network lines, comprising:
an optical interface;
a serializer/deserializer (SERDES) configured to operate at a first frequency; and
a framer configured to operate at a second frequency, the first frequency being higher than the second frequency, the framer including a digital step up converter to receive data from the SERDES and a digital step down converter to supply data to the SERDES;
wherein the step down converter includes a set of input buffers, each input buffer configured to receive a word of nibbles from the framer, the input buffers being loaded one after another, but extraction from each of the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved;
wherein the step up converter includes a set of input buffers and a register array, each input buffer configured to receive a word of nibbles from the register array, the input buffers being loaded one after another, but extraction from the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved, and wherein the set of input buffers of the step up converter includes 4 input buffers and the set of input buffers of the step down converter includes 4 input buffers;
wherein the register array is configured to receive 4 bit data from the SERDES and configured to send 32 bit data to the set of input buffers.
4. A line card for use in a node of a network to connect to optical network lines, comprising:
an optical interface;
a serializer/deserializer (SERDES) configured to operate at a first frequency; and
a framer configured to operate at a second frequency, the first frequency being higher than the second frequency, the framer including a digital step up converter to receive data from the SERDES and a digital step down converter to supply data to the SERDES;
wherein the step down converter includes a set of input buffers, each input buffer configured to receive a word of nibbles from the framer, the input buffers being loaded one after another, but extraction from each of the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved;
wherein the step up converter includes a set of input buffers and a register array, each input buffer configured to receive a word of nibbles from the register array, the input buffers being loaded one after another, but extraction from the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved, and wherein the set of input buffers of the step up converter includes 4 input buffers and the set of input buffers of the step down converter includes 4 input buffers;
wherein the multi-stage multiplexer of the step down converter is configured to receive 32 bit data and to output 4 bit data.
5. A line card for use in a node of a network to connect to optical network lines, comprising:
an optical interface;
a serializer/deserializer (SERDES) configured to operate at a first frequency; and
a framer configured to operate at a second frequency, the first frequency being higher than the second frequency, the framer including a digital step up converter to receive data from the SERDES and a digital step down converter to supply data to the SERDES;
wherein the step down converter includes a set of input buffers, each input buffer configured to receive a word of nibbles from the framer, the input buffers being loaded one after another, but extraction from each of the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved;
wherein the step up converter includes a set of input buffers and a register array, each input buffer configured to receive a word of nibbles from the register array, the input buffers being loaded one after another, but extraction from the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved, and wherein the set of input buffers of the step up converter includes 4 input buffers and the set of input buffers of the step down converter includes 4 input buffers;
wherein the multi-stage multiplexer of the step up converter is configured to receive 32 bit data and to output 4 bit data.
6. In an optical network, a framer that is connected with a serializer/deserializer (SERDES) within a line card, the framer comprising:
a digital step down converter including,
a multi-stage multiplexer being configured to supply data to the SERDES,
a set of input buffers, each input buffer configured to receive a word of nibbles from the framer, the input buffers being loaded one after another, but extraction from each of the input buffers to the multi-stage multiplexer is triggered so long as a non-reset window is preserved; and
a digital step up converter including,
a register array being configured to receive data from the SERDES;
a set of input buffers, each input buffer configured to receive a word of nibbles from the register array, the input buffers being loaded one after another, but extraction from the input buffers to a multi-stage multiplexer is triggered so long as a non-reset window is preserved;
wherein the SERDES is configured to operated at a first frequency and the framer is configured to operate at a second frequency, the first frequency being higher than the second frequency, wherein the register array is configured to receive 4 bit data from the SERDES and configured to send 32 bit data to the set of input buffers.
7. A framer as recited in claim 6 , wherein the multi-stage multiplexer of the step down converter is a 5 stage converter.
8. A line card for use in a node of a network to connect to optical network lines as recited in claim 6 , wherein the multi-stage multiplexer of the step up converter is a 2 stage converter.
9. A line card for use in a node of a network to connect to optical network lines as recited in claim 6 , wherein the set of input buffers of the step up converter includes 4 input buffers and the set of input buffers of the step down converter includes 4 input buffers.
10. A line card for use in a node of a network to connect to optical network lines as recited in claim 6 , wherein the first frequency is 622.08 MHz.
11. A line card for use in a node of a network to connect to optical network lines as recited in claim 6 wherein the second frequency is 77.76 MHz.
12. A line card for use in a node of a network to connect to optical network lines as recited in claim 6 , wherein the multi-stage multiplexer of the step down converter is configured to receive 32 bit data and to output 4 bit data.
13. A line card for use in a node of a network to connect to optical network lines as recited in claim 6 , wherein the multi-stage multiplexer of the step up converter is configured to receive 4 bit data and to output 32 bit data.
14. A line card for use in a node of a network to connect to optical network lines, comprising:
an optical interface;
a serializer/deserializer (SERDES) configured to operate at a first frequency, the SERDES being connected to the optical interface; and
a framer configured to operate at a second frequency, the first frequency being higher than the second frequency, the framer including a digital step up converter and a digital step down converter;
wherein the step down converter includes a set of 4 input buffers, each input buffer configured to receive a word of nibbles from the framer, the input buffers being loaded one after another, but extraction from each of the input buffers to a 5 stage multiplexer is triggered so long as a non-reset window is preserved, the 5 stage multiplexer being configured to supply data to the SERDES;
wherein the step up converter includes a set of 4 input buffers and a register array, each input buffer configured to receive a word of nibbles from the register array, the input buffers being loaded one after another, but extraction from the input buffers to a 2 stage multiplexer is triggered so long as a non-reset window is preserved, and the register array of the step up converter being configured to receive data from the SERDES, wherein the register array is configured to receive 4 bit data from the SERDES and configured to send 32 bit data to the set of input buffers.
15. A line card for use in a node of a network to connect to optical network lines as recited in claim 14 , wherein the first frequency is 622.08 MHz.
16. A line card for use in a node of a network to connect to optical network lines as recited in claim 15 , wherein the second frequency is 77.76 MHz.
17. In an optical network, a framer that is connected with a SERDES within a line card, the framer comprising:
a digital step down converter including,
a five stage multiplexer being configured to supply 4 bit data to the SERDES,
a set of four input buffers, each input buffer configured to receive eight sets of 4 bit data from the framer, the input buffers being loaded one after another, but extraction from each of the input buffers to the five multiplexer is triggered so long as a non-reset window is preserved; and
a digital step up converter including,
a register array being configured to receive 4 bit data from the SERDES;
a set of four input buffers, each input buffer configured to receive 8 sets of 4 bit data from the register array, the input buffers being loaded one after another, but extraction from the input buffers to a two stage multiplexer is triggered so long as a non-reset window is preserved;
wherein the SERDES is configured to operated at a frequency of is 622.08 MHz and the framer is configured to operate at a frequency of 77.76 MHz, and wherein the 2 stage multiplexer of the step down converter is configured to receive 32 bit data and to output 4 bit data.
18. A line card for use in a node of a network to connect to optical network lines as recited in claim 17 , wherein the five multiplexer of the step up converter is configured to receive 4 bit data and to output 32 bit data.
19. A method for transferring data between a framer and a serializer/deserializer (SERDES) of a line card used in an optical network, comprising:
when the data is being transferred from the framer to the SERDES,
receiving data from the framer, the framer operating at a first frequency,
loading the data in a set of input buffers of a digital step down converter, the input buffers being loaded one after another, each of the input buffers holding a word of nibbles,
extracting the data from each of the input buffers of the digital step down converter to a multi-stage multiplexer of the step down converter, the input buffers being extracted one after another, the extracting being triggered so long as a non-reset window of the step down converter is preserved,
transmitting the data from the multi-stage multiplexer of the step down converter to the SERDES, the SERDES configured to operate at a second frequency, the first frequency being higher than the second frequency; and
when the data is being transferred from the SERDES to the framer,
transferring the data from the SERDES to a register array,
receiving the data from the register array,
loading the data in a set of input buffers of a digital step up convertor, the input buffers being loaded one after another, each of the input buffers holding a word of nibbles,
extracting the data from each of the input buffers of the digital step up converter to a multi-stage multiplexer of the step up converter, the input buffers being extracted one after another, the extracting being triggered so long as a non-reset window of the step up converter is preserved,
transmitting the data from the multi-stage multiplexer of the step up converter to the framer, and wherein the multi-stage multiplexer of the step down converter is a 5 stage converter.
20. A method for transferring data between a framer and a serializer/deserializer (SERDES) of a line card used in an optical network as recited in claim 19 , wherein the multi-stage multiplexer of the step up converter is a 2 stage converter.
21. A method for transferring data between a framer and a serializer/deserializer (SERDES) of a line card used in an optical network as recited in claim 20 , wherein the first frequency is 622.08 MHz and the second frequency is 77.76 MHz.
22. A method for transferring data between a framer and a serializer/deserializer (SERDES) of a line card used in an optical network as recited in claim 21 , wherein the register array is configured to receive 4 bit data from the SERDES and configured to send 32 bit data to the set of input buffers.
23. A method for transferring data between a framer and a serializer/deserializer (SERDES) of a line card used in an optical network as recited in claim 22 , wherein the multi-stage multiplexer of the step down converter is configured to receive 32 bit data and to output 4 bit data.
24. A method for transferring data between a framer and a serializer/deserializer (SERDES) of a line card used in an optical network as recited in claim 23 , wherein the multi-stage multiplexer of the step up converter is configured to receive 32 bit data and to output 4 bit data.
25. A method for transferring data between a framer and a serializer/deserializer (SERDES) of a line card used in an optical network as recited in claim 23 , wherein extracting the data from each of the input buffers of the digital step down converter to a multi-stage multiplexer of the step down converter includes,
extracting the data from a particular one of the input buffers of the digital step down converter to a multi-stage multiplexer of the step down converter when at least one additional input buffer has been filled after the particular one of the input buffers has been filled.
26. A method for transferring data between a framer and a serializer/deserializer (SERDES) of a line card used in an optical network as recited in claim 23 , wherein extracting the data from each of the input buffers of the digital step up converter to a multi-stage multiplexer of the step up converter includes,
extracting the data from a particular one of the input buffers of the digital step up converter to a multi-stage multiplexer of the step up converter when at least one additional input buffer has been filled after the particular one of the input buffers has been filled.