Systems and methods for implementing content sensitive routing over a wide area network (WAN)

• US 20030105829A1
• Filed: 11/22/2002
• Published: 06/05/2003
• Est. Priority Date: 11/28/2001
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: Yotta Yotta Incorporated (Dell Technologies Inc.)
• Inventors: Hayward, Geoff
• Granted Patent: US 7,194,656 B2
• Time in Patent Office: Days
• US Class Current: 709/214
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/10015 Access to distributed or replicated servers, e.g. using brokers
• CPC Class Codes: H04L 67/1021 based on client or server locations
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 67/2885 Hierarchically arranged intermediate devices, e.g. for hierarchical caching
• CPC Class Codes: H04L 67/5651 Reducing the amount or size of exchanged application data
• CPC Class Codes: H04L 67/5682 Policies or rules for updating, deleting or replacing the stored data
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

Systems and methods for optimizing storage network functionality. The methods and systems of the present invention are particularly useful for optimizing storage network performance for cases in which some components of the network may be separated by significant distances and/or which include communication links with relatively limited bandwidth. In certain aspects, the present invention provides methods and systems for implementing access to and management of geographically distributed storage resources through multiple peer-to-peer storage network array management functions (AMFs) that may also be geographically distributed. The methods and systems of the present invention, in certain aspects, provide geographically aware cache sharing, cache replication, cache coherence, traffic routing, redundancy group structure, source and destination selection, pre-fetching of data, message gathering and other useful features.

Claims

1. A system for implementing hierarchical distributed cache coherence in a storage network, the system comprising:

a redundancy group (RG) including a first plurality of storage resources and a second plurality of storage resources located remotely from the first plurality of storage resources;

an AMF access group (AAG), including a plurality of AMFs that share read and write access to the RG, wherein the AAG includes two or more local AMF access groups (LAAGs), each LAAG being either remote from other LAAGs or communicably coupled to other LAAGs by a low bandwidth network link; and

a proxy node configured to manage communications between the two or more LAAGs so as to minimize or eliminate inter-LAAG meta-data traffic for read and write operations.

2. The system of claim 1, wherein the proxy node is implemented in one of the plurality of AMFs or as a separate AMF.

3. A method for implementing hierarchical distributed cache coherence in a storage network, the network comprising a redundancy group (RG) including a first plurality of storage resources and a second plurality of storage resources located remotely from the first plurality of storage resources, and an AMF access group (AAG), including a plurality of AMFs that share read and write access to the RG, wherein the AAG includes two or more local AMF access groups (LAAGs), each LAAG being either remote from other LAAGs or communicably coupled to other LAAGs by a low bandwidth network link, the method comprising:

receiving a data access request from a host by a first AMF in a first LAAG;

sending meta-data related associated with the access request to a second AMF in the LAAG, wherein the second AMF is configured to act as a proxy agent for the LAAG; and

sending, from the second AMF, the meta-data to the proxy agent for each of the other LAAGs.

4. The method of claim 3, wherein the data access request is a request to read data from a RG.

5. The method of claim 3, wherein the data access request is a request to write data to a RG.

6. The method of claim 5, wherein the meta-data includes a write invalidate command.

7. A method for implementing preferred target selection for read operations by a given AMF so that the read operations are directed toward data mirrors residing within the nearest LRG.

8. A method for implementing preferred AMF selection, and source mirror selection for rebuild and data transfer operations so that read/write traffic is confined as much as possible to the LRG associated with the target storage resource.

9. A method for implementing preferred target selection for read operations by a given AMF in fail-over scenarios so that these read operations are directed toward the nearest surviving data mirror.

10. A method for implementing preferred target selection for read operations by a given AMF so that these read operations are directed toward data mirrors residing within the nearest LRG.

11. A method for implementing adaptive geographically aware RAID.