Method and apparatus for introducing differential delay between virtually concatenated tributaries
View Patent ↗In one embodiment, the invention is an apparatus for testing differential delay correction of network elements using virtual concatenation. The apparatus includes a first PRBS (pseudo-random bit stream) generator dedicated to a first tributary. The apparatus also includes an interface between the first PRBS generator and a tester. The apparatus further includes an interface between the first PRBS generator and a device under test. The apparatus may further include a second PRBS dedicated to a second tributary. The apparatus may also include a control logic block to control the first PRBS generator and the second PRBS generator, and coupled to the first PRBS generator and the second PRBS generator.
1. A method of introducing programmable differential delay between tributaries within a virtually concatenated channel comprising:
providing a first seed value reflecting a delay to date for a first virtual channel with respect to other virtual channels;
programming a multi-frame indicator to the delay; and
generating a first series of synchronous payload envelopes (SPEs) for a first tributary using a first Pseudo-random Bit Stream (PRBS) having the first seed value.
2. The method of claim 1 , further comprising:
Transmitting the first series of SPEs.
3. The method of claim 2 , further comprising:
Providing a second seed value reflecting a delay to date for a second virtual channel with respect to other virtual channels.
4. The method of claim 3 , further comprising:
Generating a second series of synchronous payload envelopes (SPEs) for a second tributary using a second PRBS having the second seed value.
5. The method of claim 4 , further comprising:
Transmitting the second series of SPEs.
6. The method of claim 5 , further comprising:
Determining results of generating and transmitting the first series of SPEs and the second series of SPEs.
7. An apparatus for testing transmission using virtual concatenation comprising:
Means for providing a first seed value reflecting a delay to date for a first virtual channel with respect to other virtual channels;
Means for providing a multi-frame indicator; and
Means for generating a first series of synchronous payload envelopes (SPEs) for a first tributary using a first Pseudo-random Bit Stream (PRBS) with the first seed value.
8. The apparatus of claim 7 , further comprising:
Means for transmitting the first series of SPEs.
9. The apparatus of claim 8 , further comprising:
Means for providing a second seed value reflecting a delay to date for a second virtual channel with respect to other virtual channels;
Means for generating a second series of synchronous payload envelopes (SPEs) for a second tributary with the second seed value; and
Means for transmitting the second series of SPEs.
10. The apparatus of claim 9 , further comprising:
Means for evaluating results of generating and transmitting the first series of SPEs and the second series of SPEs.