Patent · US Expired

Hub and interface for isochronous token ring

US5687356A · kind A · utility

25Cited by
18References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 27, 1995
Grant dateNov 11, 1997
Priority date
Expiry dateDec 27, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2012/6459
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A hub featuring ports for attachment of stations to a LAN comprises concentration logic (14) for the handling of multiplexed incoming and outgoing Token-Ring and isochronous signal streams. The concentration logic comprises clock recovery logic (42) from incoming Token-Ring packet data stream (40), for regeneration of Differential Manchester encoded data on output (400), and recovering of Token-Ring clock (401). A cycle framing generator (43) receives a 125 us synchronization clock from the hub backplane (402), and the Token-Ring clock (401), and generates control signals (403) to each of the 10 ports. Each port is comprised of a port transmit interface (44), and a port receive interface (45). Data from a connected station is input (404) to port receive interface (45). Token-Ring packet Differential Manchester encoded data are output (406) to the next active port, specifically to its port transmit interface, along with a recovered strobe clock (405), while ISO data are output (407) to switch (46). The switch and other concentration logic receive a hub local clock (412). Isochronous traffic interchanges with the hub backplane through leads 410 and 411; between ports or between ports…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.