Loosely coupled mass storage computer cluster

• US 5,996,089 A
• Filed: 12/16/1997
• Issued: 11/30/1999
• Est. Priority Date: 10/24/1995
• Status: Expired due to Term

• Current Assignee: SeaChange International Incorporated
• Original Assignee: SeaChange International Incorporated
• Inventors: Mann, Bruce E., Ywoskus, John A., McGrath, Edward J., Carlozzi, Michael D., Trasatti, Philip J.
• Primary Examiner(s): Beausoliel, Jr., Robert W.
• Assistant Examiner(s): Iqbal, Nadeem
• Application Number:
  US08/991,278
• Time in Patent Office: 714 Days
• Field of Search: 370/216, 370/217, 370/218, 370/219, 370/220, 370/225, 370/227, 370/228, 370/241, 370/242, 370/244, 395/182.04, 714/6, 714/2, 714/4, 714/8, 714/25, 714/37, 714/42, 714/43, 714/48, 714/770
• US Class Current: 714/6.31
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 11/2028 eliminating a faulty processor or activating a spare
• CPC Class Codes: G06F 11/2038 with a single idle spare processing component
• CPC Class Codes: G06F 2211/1028 Distributed, i.e. distributed RAID systems with parity
• CPC Class Codes: G06F 2211/1045 Nested RAID, i.e. implementing a RAID scheme in another RAID scheme
• CPC Class Codes: H04N 7/17336 Handling of requests in head-ends

Abstract

A method and apparatus redundantly store data, in particular video data objects, in a distributed computer system having at least three processor systems, each processor system being connected in point to point two way channel interconnection with each other processor system. The data is stored in a redundant fashion both at the computer system level as well as the processor system level. Accordingly, the failure of a single processor does not adversely affect the integrity of the data. The computer system can also overlay a switching system connected in a ring fashion for providing a fault tolerance to the failure of a single connected processor system at the switch level. Accordingly, there results a fault tolerant data distribution system.

Claims

1. A redundant switch having n interruptible inputs, n interrupting inputs and n outputs comprising

(n+1) switched systems, each switch system having at least two control inputs, a first input, a second input, a third input, and a fourth input, and a first output and a second output, each switched system being connected at its second output to an interrupting signal generator, an interrupting output of said associated signal generator being connected to the second input of said connected switched system,

said switched systems being interconnected in a ring structure so that each switched system further has an interruptible input signal connected to the first input, the second input of a first neighbor switched system connected to the third input, and the interruptible input from the other neighbor switched system on the ring connected to the fourth input,

each said switched system having switching circuitry responsive to said control inputs for switching any of its inputs to at least its first output, and for connecting either of its first and fourth inputs to its second output, and

a control system providing said control inputs of said switched system.

3. The redundant switch of claim 1 wherein said control system can effectively rotate switching signal functions in either direction around the ring.

2. A redundant switch having n interruptible inputs, n interrupting inputs and n outputs comprising

(n+1) switched systems, each switched system having at least two control inputs, four signal inputs, and two signal outputs, each switched system being connected at one of its outputs to an associated interrupting signal generator, and an interrupting output of said associated signal generator being connected to an input of said connected switched system,

said switched systems being interconnected in a ring structure so that each switched system is connected to a first and a second neighbor switched system,

each said switched system having switching circuitry responsive to said control inputs for selectively switching its inputs to its outputs, and

a control system for providing said control inputs to said switched systems to enable said switched systems to effectively rotate signal switching functions one position in either direction around the ring so that a failed signal generator can be bypassed and the signals on said n first outputs continue uninterrupted.