Combined wavelength division multiplexing, time division multiplexing, and asynchronous packet switching with common time reference
US6778536B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 2000 |
| Grant date | Aug 17, 2004 |
| Priority date | — |
| Expiry date | Mar 28, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q2011/005
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A switching method is designed to operate with very high-speed wavelength division multiplexing (WDM) links, i.e., with multiple lambdas. The switching and data packet forwarding method combines the advantages of both synchronous and asynchronous data packet switching modes. In the synchronous switching mode, a time frame switching method based on predefined switching schedules that are responsive to a global common time reference, where the global common time reference is divided into a plurality of contiguous periodic super cycles, time cycles and time frames. The plurality of data packets contained in each of the time frames can be switched from any incoming WDM channel to any subset of outgoing WDM channels. The outcome of this switching method is called fractional lambda switching. For the asynchronous switching mode data packets that do not need guaranteed performance are separated from flows of data packets that require a deterministic service. The asynchronous data packets are routed according to header information and then combined back into the optical WDM channels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.