Managing storage resources in decentralized networks

• US 7,251,689 B2
• Filed: 03/27/2002
• Issued: 07/31/2007
• Est. Priority Date: 03/27/2002
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Wesley, Ajamu A.
• Primary Examiner(s): Wiley; David
• Assistant Examiner(s): DENNISON, JERRY B
• Application Number:
  US10/107,960
• Publication Number:
  US 20030187973A1
• Time in Patent Office: 1,952 Days
• Field of Search: 709/220, 709/224
• US Class Current: 709/224
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/45 Network directories; Name-to-address mapping
• CPC Class Codes: H04L 63/10 for controlling access to devices or network resources
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/104 Peer-to-peer [P2P] networks
• CPC Class Codes: H04L 67/1044 Group management mechanisms management of multicast group membership H04L12/185; reconfiguring of node membership in a computing system to eliminate errors G06F11/1425
• CPC Class Codes: H04L 67/1046 Joining mechanisms
• CPC Class Codes: H04L 67/1048 Departure or maintenance mechanisms
• CPC Class Codes: H04L 67/1068 Discovery involving direct consultation or announcement among potential requesting and potential source peers
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04L 67/51 Discovery or management thereof, e.g. service location protocol [SLP] or web services
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

Methods, systems, and computer program products are disclosed for managing storage resources in decentralized networks. Persistent identifiers are defined for nodes, allowing nodes to be identified across sessions and invocations, even though they re-enter the network with a different network address. Paths taken by content resources as they traverse the network (e.g. which nodes forwarded the content) are persisted, along with reputation information about nodes (e.g. indicating how successful they are at answering queries from peers). Trust relationships can be derived using the persisted information. A tiered broadcast strategy is defined for reducing the number of messages exchanged. Preferred embodiments leverage a web services implementation model.

Claims

1. A programmatic method of managing storage resources in a decentralized network, comprising steps of:

creating, for each of a plurality of nodes in the decentralized network upon an initial entry of the node into the network, a unique persistent node identifier to uniquely identify the node across all of the node'"'"'s entries into the network even if a different network address is assigned to the node upon a subsequent entry into the network, wherein the unique persistent node identifier for each of the nodes comprises;

(i) an original network address assigned to the node upon the initial entry of the node into the network;

(ii) a date of the initial entry;

(iii) a time of the initial entry; and

(iv) an identifier of a network domain in which the initial entry occurred;

creating, for each of the nodes in the decentralized network, a mapping usable for resolving current network addresses to unique persistent node identifiers, wherein the mapping created for each of the nodes comprises an entry for each other one of the nodes in the network that is known to the each node and each of the entries specifies (i) the unique persistent node identifier of the other one and (ii) the current network address of the other one, and wherein the entries in the mapping for each of the nodes are revised when the each node learns that any of the known nodes has a changed current network address and when any additional node in the network becomes known to the each node;

dynamically evaluating behavior of storage-providing ones of the nodes, wherein the storage-providing nodes are those ones of the nodes that provide dynamic, on-demand allocation of available storage resources to storage-requesting ones of the nodes in the network;

maintaining on-going knowledge of the dynamically evaluated behavior of each of the storage-providing nodes;

consulting the mapping, by the storage-requesting nodes when presented with the current network address of at least one selected one of the storage-providing nodes, to obtain the unique persistent node identifier from the entry for each of the selected ones, such that the maintained on-going knowledge of the dynamically evaluated behavior of the selected ones of the storage-providing nodes can be determined, even if the current network address of the selected ones of the storage-providing nodes changes; and

using the maintained knowledge to access the storage resources of at least one of the selected storage-providing nodes, wherein the access uses the current network address of each of the at least one of the selected storage-providing nodes.

2. The method according to claim 1, wherein the dynamically evaluated behavior of each of the storage-providing nodes comprises how efficient that storage-providing node is at handling storage requests from the storage-requesting nodes.

3. The method according to claim 1, wherein the dynamically evaluated behavior of each of the storage-providing nodes comprises how well that storage-providing node responds to storage requests from the storage-requesting nodes.

4. The method according to claim 1, wherein the dynamically evaluated behavior of each of the storage-providing nodes comprises currently-available storage capacity of the node'"'"'s storage resources.

5. The method according to claim 1, wherein the dynamically evaluated behavior of each of the storage-providing nodes comprises a success measure indicating whether that storage-providing node responded satisfactorily to prior storage requests from the storage-requesting nodes.

6. The method according to claim 1, wherein the dynamically evaluated behavior of each of the storage-providing nodes further comprises a specification of content that is currently available from the storage resources of that storage-providing node.

7. The method according to claim 1, wherein:

the consulting step occurs responsive to determining, by a particular one of the storage-requesting nodes in the network, that it needs storage resources; and

the using step further comprises the steps of;

using, by the particular one of the storage-requesting nodes, the maintained on-going knowledge of the behavior of the selected ones of the storage-providing nodes to select a particular one of the selected storage-providing nodes which, according to the maintained on-going knowledge, is currently able to provide the needed storage resources; and

requesting, by the particular one of the storage-requesting nodes from the particular one of the storage-providing nodes using the current network address of the particular one of the storage-providing nodes, allocation of the needed storage resources.

8. The method according to claim 4, wherein:

the consulting step occurs responsive to determining, by a particular one of the storage-requesting nodes, that it needs to store content in storage resources; and

the using step further comprises the steps of;

using, by the particular one of the storage-requesting nodes, the maintained on-going knowledge of the behavior of the selected ones of the storage-providing nodes to select a particular one of the selected storage-providing nodes which, according to the maintained on-going knowledge, has storage resources with sufficient currently-available storage capacity for storing the content for the particular one of the storage-requesting nodes; and

requesting, by the particular one of the storage-requesting nodes from the particular one of the storage-providing nodes using the current network address of the particular one of the storage-providing nodes, storage of the content.

9. The method according to claim 1, wherein at least one of the storage-providing nodes is also one of the storage-requesting nodes.

10. The method according to claim 2, wherein:

the consulting step occurs responsive to determining, by a particular one of the storage-requesting nodes in the network, that it needs storage resources; and

the using step further comprises the steps of;

using, by the particular one of the storage-requesting nodes, the maintained on-going knowledge of the behavior of the selected ones of storage-providing nodes to select a particular one of the selected storage-providing nodes which, according to the maintained on-going knowledge, can efficiently provide the needed storage resources; and

requesting, by the particular one of the storage-requesting nodes from the particular one of the storage-providing nodes using the current network address of the particular one of the storage-providing nodes, allocation of the needed storage resources.

11. The method according to claim 5, wherein:

the consulting step occurs responsive to determining, by a particular one of the storage-requesting nodes in the network, that it needs storage resources; and

the using step further comprises the steps of;

using, by the particular one of the storage-requesting nodes, the maintained on-going knowledge of the behavior of the selected ones of the storage-providing nodes to select a particular one of the storage-providing nodes which, according to the maintained on-going knowledge, has a relatively high success measure for responding to prior storage requests satisfactorily; and

requesting, by the particular one of the storage-requesting nodes from the particular one of the storage-providing nodes using the current network address of the particular one of the storage-providing nodes, allocation of the needed storage resources.

12. The method according to claim 6, wherein:

the consulting step occurs responsive to determining, by a content-needing one of the storage-requesting nodes, that it needs to retrieve content from storage resources; and

the using step further comprises the steps of;

using, by the content-needing one of the storage-requesting nodes, the maintained on-going knowledge of the behavior of the selected ones of the storage-providing nodes to select a particular one of the selected storage-providing nodes whose specification of currently available content, according to the maintained on-going knowledge, includes the content that the content-needing one of the storage-requesting nodes needs to retrieve; and

requesting, by the content-needing one of the storage-requesting nodes from the particular one of the storage-providing nodes using the current network address of the particular one of the storage-providing nodes, retrieval of the content.

13. The method according to claim 1, wherein the network is a peer-to-peer network.

14. A system for managing storage resources in an ad hoc network, comprising:

an ad hoc network comprising a plurality of nodes;

means for creating, for each of the plurality of nodes upon an initial entry of the node into the network, a unique persistent node identifier to uniquely identify the node across all of the node'"'"'s entries into the network even if a different network address is assigned to the node upon a subsequent entry into the network, wherein the unique persistent node identifier for each of the nodes comprises;

(i) an original network address assigned to the node upon the initial entry of the node into the network;

(ii) a date of the initial entry;

(iii) a time of the initial entry; and

(iv) an identifier of a network domain in which the initial entry occurred;

means for creating, for each of the nodes in the decentralized network, a mapping usable for resolving current network addresses to unique persistent node identifiers, wherein the mapping created for each of the nodes comprises an entry for each other one of the nodes in the network that is known to the each node and each of the entries specifies (i) the unique persistent node identifier of the other one and (ii) the current network address of the other one, and wherein the entries in the mapping for each of the nodes are revised when the each node learns that any of the known nodes has a changed current network address and when any additional node in the network becomes known to the each node;

means for dynamically evaluating behavior of storage-providing ones of the nodes, wherein the storage-providing nodes are those ones of the nodes that provide dynamic, on-demand allocation of available storage resources to storage-requesting ones of the nodes in the network;

means for maintaining on-going knowledge of the dynamically evaluated behavior of each of the storage-providing nodes;

means for consulting the mapping, by the storage-requesting nodes when presented with the current network address of at least one selected one of the storage-providing nodes, to obtain the unique persistent node identifier from the entry for each of the selected ones, such that the maintained on-going knowledge of the dynamically evaluated behavior of the selected ones of the storage-providing nodes can be determined, even if the current network address of the selected ones of the storage-providing nodes changes; and

means for using the maintained knowledge to access the storage resources of at least one of the selected storage-providing nodes, wherein the access uses the current network address of each of the at least one of the selected storage-providing nodes.

15. The system according to claim 14, wherein the dynamically evaluated behavior of each of the storage-providing nodes comprises how efficient that storage-providing node is at handling storage requests from the storage-requesting nodes and wherein:

the means for consulting is operable responsive to means for determining, by a particular one of the storage-requesting nodes in the network, that it needs storage resources; and

the means for using further comprises;

means for using, by the particular one of the storage-requesting nodes, the maintained on-going knowledge of the behavior of the selected ones of the storage-providing nodes to select a particular one of the storage-providing nodes which, according to the maintained on-going knowledge, can efficiently provide the needed storage resources; and

means for requesting, by the particular one of the storage-requesting nodes from the particular one of the storage-providing nodes using the current network address of the particular one of the storage-providing nodes, allocation of the needed storage resources.

16. The system according to claim 14, wherein the dynamically evaluated behavior of each of the storage-providing nodes comprises currently-available storage capacity of the node'"'"'s storage resources and wherein:

the means for consulting is operable responsive to means for determining, by a particular one of the storage-requesting nodes, that it needs to store content in storage resources; and

the means for using further comprises;

means for using, by the particular one of the storage-requesting nodes, the maintained on-going knowledge of the behavior of the selected ones of the storage-providing nodes to select a particular one of the storage-providing nodes whose storage resources, according to the maintained on-going knowledge, have sufficient currently-available storage capacity for storing the content; and

means for requesting, by the particular one of the storage-requesting nodes from the particular one of the storage-providing nodes using the current network address of the particular one of the storage-providing nodes, storage of the content.

17. The system according to claim 14, wherein at least one of the storage-providing nodes is also one of the storage-requesting nodes.

18. A computer program product for managing storage resources in an ad hoc network, where a plurality of nodes making up the network may change over time, the computer program product embodied on one or more computer-readable media and comprising computer-readable program code that, when executed:

creates, for each of the plurality of nodes upon an initial entry of the node into the network, a unique persistent node identifier to uniquely identify the node across all of the node'"'"'s entries into the network even if a different network address is assigned to the node upon a subsequent entry into the network, wherein the unique persistent node identifier for each of the nodes comprises;

(i) an original network address assigned to the node upon the initial entry of the node into the network;

(ii) a date of the initial entry;

(iii) a time of the initial entry; and

(iv) an identifier of a network domain in which the initial entry occurred;

creates, for each of the nodes in the decentralized network, a mapping usable for resolving current network addresses to unique persistent node identifiers, wherein the mapping created for each of the nodes comprises an entry for each other one of the nodes in the network that is known to the each node and each of the entries specifies (i) the unique persistent node identifier of the other one and (ii) the current network address of the other one, and wherein the entries in the mapping for each of the nodes are revised when the each node learns that any of the known nodes has a changed current network address and when any additional node in the network becomes known to the each node;

dynamically evaluates behavior of storage-providing ones of the nodes, wherein the storage-providing nodes are those ones of the nodes that provide dynamic, on-demand allocation of available storage resources to storage-requesting ones of the nodes in the network;

maintains on-going knowledge of the dynamically evaluated behavior of each of the storage-providing nodes;

consults the mapping, by the storage-requesting nodes when presented with the current network address of at least one selected one of the storage-providing nodes, to obtain the unique persistent node identifier from the entry for each of the selected ones, such that the maintained on-going knowledge of the dynamically evaluated behavior of the selected ones of the storage-providing nodes can be determined, even if the current network address of the selected ones of the storage-providing nodes changes; and

uses the maintained knowledge to access the storage resources of at least one of the selected storage-providing nodes, wherein the access uses the current network address of each of the at least one of the selected storage-providing nodes.

19. The computer program product according to claim 18, wherein the dynamically evaluated behavior of each of the storage-providing nodes comprises a success measure indicating whether that storage-providing node responded satisfactorily to prior storage requests from the storage-requesting nodes and wherein:

the computer-readable program code that consults the mapping executes responsive to determining, by a particular one of the storage-requesting nodes in the network, that it needs storage resources; and

the computer-readable program code that uses the maintained knowledge further comprises computer-readable program code that, when executed, further comprises;

using, by the particular one of the storage-requesting nodes, the maintained on-going knowledge of the behavior of the selected ones of the storage-providing nodes to select a particular one of the storage-providing nodes which, according to the maintained on-going knowledge, has a relatively high success measure for responding to prior storage requests satisfactorily; and

requesting, by the particular one of the storage-requesting nodes from the particular one of the storage-providing nodes using the current network address of the particular one of the storage-providing nodes, allocation of the needed storage resources.

20. The computer program product according to claim 18, wherein the dynamically evaluated behavior of each of the storage-providing nodes further comprises a specification of content that is currently available from that storage-providing node and wherein:

the computer-readable program code that consults the mapping executes responsive to determining, by a content-needing node, that it needs to retrieve content from storage resources; and

the computer-readable program code that uses the maintained knowledge further comprises computer-readable program code that, when executed, further comprises;

using, by the content-needing one of the storage-requesting nodes, the maintained on-going knowledge of the behavior of the selected ones of the storage-providing nodes to select a particular one of the storage-providing nodes whose specification of currently available content, according to the maintained on-going knowledge, includes the content that the content-needing one of the storage-requesting nodes needs to retrieve; and

requests, by the content-needing one of the storage-requesting nodes from the particular one of the storage-providing nodes using the current network address of the particular one of the storage-providing nodes, retrieval of the content.