Symmetrically switched multimedia system

• US 5,612,897 A
• Filed: 03/21/1996
• Issued: 03/18/1997
• Est. Priority Date: 03/21/1996
• Status: Expired due to Term

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Digital Equipment Corporation (HP Inc.)
• Inventors: Rege, Satish L.
• Primary Examiner(s): Voeltz, Emanuel T.
• Assistant Examiner(s): PEESO, THOMAS R
• Application Number:
  US08/620,110
• Time in Patent Office: 362 Days
• Field of Search: 364/514 C, 370/60, 370/53, 370/85.5, 395/154, 395/275, 348/6, 348/7, 348/16, 348/17
• US Class Current: 709/219
• CPC Class Codes: G06F 2211/1028 Distributed, i.e. distributed RAID systems with parity
• CPC Class Codes: H04L 49/252 Store and forward routing
• CPC Class Codes: H04L 49/254 Centralised controller, i.e. arbitration or scheduling
• CPC Class Codes: H04L 49/3027 Output queuing
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/611 for multicast or broadcast systems for broadcast or conference H04L12/18; arrangements for broadcast or distribution combined with broadcast H04H20/00; arrangements for broadcast applications with a direct linkage to broadcast information or to broadcast space-time H04H60/00; selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS], H04W4/06
• CPC Class Codes: H04L 65/612 for unicast
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A multimedia system for delivering multimedia content items to customer premises equipment via a circuit of a communications network includes a plurality of substantially identical nodes connected in a symmetric mesh. Each node includes a switch and a server. The server includes disk storage for the multimedia content, a switch interface for connecting the server to the switch, and a network adapter for connecting the server to the communications network. Source nodes fetch data from disk, routing nodes transport data among nodes, and destination nodes transport the data to the communications network. The switch is a store-and-forward switch including direct memory access engine for pulling data into the switch, and a buffer for storing data to be forwarded to another switch. Portions of each content item are distributed substantially equally over the available storage media to improve load balancing and data redundancy.

Claims

1. An apparatus for delivering multimedia items to customers via a communications network, comprising:

a plurality of nodes, each node including a switch connected to a server, each server including means for connecting to the communications network and means for storing a different portion of a selected multimedia item, and the switch including a first direct memory access engine connected to an input port of the switch, the first direct memory access engine for acquiring the different portions from an adjacent node via the data and control network, and an output buffer connected to an output port, the output buffer for storing the different portions acquired by the first direct memory access engine; and

a data and control network symmetrically connecting the plurality of nodes to each other.

2. The apparatus as in claim 1 wherein the server further comprises:

a processor, a memory, and input/output interfaces connected to each other and the means for storing by a server bus.

3. The apparatus as in claim 2 wherein the server further comprises means for generating packets to route the different portions among the plurality of nodes, each packet includes a payload representing the portions of the multimedia content items.

4. The apparatus as in claim 3 wherein each node includes a unique address, and each packet includes a source address and a destination address of a source node and a destination node.

5. The apparatus as in claim 1 wherein the switch further comprises:

a second direct memory access engine connected to a server port of the switch, the second direct memory access engine for transferring the different portions between the switch and the server of the node; and

a server buffer for storing the different portions transferred between the switch and the server.

6. The apparatus as in claim 5 wherein the switch further comprises:

a deadlock resolution buffer for storing the different portions if the output buffer and server buffer are full.

7. The apparatus as in claim 1 wherein data and control network routes the different portions uni-directionally among the plurality of nodes.

8. The apparatus as in claim 7 wherein the data and control network symmetrically connects the plurality of nodes in a ring.

9. The apparatus as in claim 7 wherein the data and control network symmetrically connects the plurality of nodes in a plane.

10. The apparatus of claim 7 wherein the data and control network symmetrically connects the plurality of nodes in a parallelpiped.

11. The apparatus as in claim 1 wherein the means for storing is a redundant array of independent disks, and wherein the different portions of each multimedia item are distributed substantially equally among the independent disks of the redundant array.

12. A method for delivering multimedia items to customers via a communications network, comprising the steps of:

distributing portions of each multimedia item over a plurality of nodes, each node including a switch connected to a server, each server including means for connecting to the communications network and means for storing a different portion of a selected multimedia item, and the switch including a first direct memory access engine connected to an input port of the switch, the first direct memory access engine for acquiring the different portions from an adjacent node via the data and control network, and an output buffer connected to an output port, the output buffer for storing the different portions acquired by the first direct memory access engine;

fetching, in response to a customer demand, a portion of a selected multimedia item from the storage means of a source one of the plurality of nodes;

routing the portion to a destination one of the plurality of nodes using a data and control network symmetrically connecting the plurality of nodes;

presenting the portion to the communications network connected to the destination node.