Layered session data unit frame
US5148482A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 30, 1991 |
| Grant date | Sep 15, 1992 |
| Priority date | — |
| Expiry date | May 30, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/40
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A layered session data unit frame (300) is provided wherein a first frame (200), designated a session data unit("SDU"), containing user information (209), a link control field (205) and an encryption field (207), is divided into a plurality of smaller frames (321, 323), each having an information field and designated a link data unit("LDU"). According to the invention, the SDU user information (209) is allocated into the information fields (211, 213) of the plurality of LDU's. The SDU link control field (205) is divided into a plurality of sub-fields and imbedded into the information fields of a first group of LDU's. The SDU encryption field (207) is divided into a plurality of sub-fields and imbedded into the information fields of a second group of LDU's. The sub-fields may be distributed throughout the LDU's in a generally uniform fashion. For instance, where the user information comprises coded voice words, the sub-fields may be separated by 30 msec words such that voice may be produced during the transmission of the field without any audio delay.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.