The invention provides a method and system for creating an innovative file system that separates its directory presentation from its data store. The method and system include processing, division, distribution, managing, synchronizing, and reassembling of file system objects that does not delay the presentation of the content to the user, but also uses a reduced amount of storage space. The invention includes the ability to manage and control the integrity of the files distributed across the network, and the ability to serve and reconstruct files in real time using a Virtual File Control System.

Method and system for managing distributed content and related metadata

An architecture and methodology for designing, deploying, and managing a distributed application onto a distributed computing system is described.

Architecture for distributed computing system and automated design, deployment, and management of distributed applications

Large payload files are selectively partitioned in blocks and the blocks distributed to a plurality of distribution stations at the edge of the network qualified to have the data. Each qualified station decides how much and what portion of the content to save locally, based on information such as network location and environment, usage, popularity, and other distribution criteria defined by the content provider. Different pieces of a large payload file may be available from different nodes, however, when a user requests access to the large payload file, for example, through an application server, a virtual file control system creates an illusion that the entire file is present at the connected node. However, since only selective portions of the large payload file may actually be resident at that node's storage at the time of request, a cluster of distribution servers at the distribution station may download the non-resident portions of the file as the application server is servicing the user. The download may be in parallel and usually from the least congested nodes. New nodes added to the network learn from other nodes in the network what content they should have and download the required content, in a desired amount, onto their local storage devices from the nearest and least congested nodes without interrupting network operation. Each node manages its local storage and decides what content to prune based on information such as usage patterns.

Method and apparatus for managing a plurality of servers in a content delivery network

A system ( 120 ) detects transmission of potentially unwanted e-mail messages. The system ( 120 ) may receive e-mail messages and generate hash values based on one or more portions of the e-mail messages. The system ( 120 ) may then determine whether the generated hash values match hash values associated with prior e-mail messages. The system ( 120 ) may determine that one of the e-mail messages is a potentially unwanted e-mail message when one or more of the generated hash values associated with the e-mail message match one or more of the hash values associated with the prior e-mail messages.

Hash-based systems and methods for detecting and preventing transmission of unwanted e-mail

In a first exemplary media implementation, one or more processor-accessible media include processor-executable instructions that, when executed, direct a system to perform actions that include: accumulating host status information at multiple hosts; and sending the accumulated host status information from the multiple hosts In a second exemplary media implementation, one or more processor-accessible media include processor-executable instructions that, when executed, direct a system to perform actions that include: receiving host status information from multiple hosts; and making load balancing decisions responsive to the received host status information In a third exemplary media implementation, one or more processor-accessible media include processor-executable instructions that, when executed, direct a system to perform actions that include: determining health and load information on a per application basis; and selecting an application from among multiple applications responsive to the health and load information

Network load balancing with host status information

A cluster server apparatus operable to continuously carrying out data distribution to terminals even if among a plurality of cache servers of the cluster server apparatus cache server, while optimally distributing loads on the plurality of cache servers. A cluster control unit of the cluster server apparatus distributes requests from the terminals based on the load of each of the plurality of cache servers. A cache server among the plurality of cache servers distributes, requested data (streaming data) to a terminal if the requested data is stored in a streaming data storage unit of the cache server, while distributing data from a content server the requested data if it is not stored in the streaming data storage unit. The data distributed from the content server is redundantly stored in the respective streaming data storage units of two or more cache servers. One cache server detects the state of distribution of the other cache server that stores the same data as that stored in the one cache server. If the one cache server becomes unable to carry out distribution, the other cache server continues data distribution instead.

Cluster server apparatus

PROBLEM TO BE SOLVED: To provide a cluster server device, with which data can be distributed to terminal equipment while performing the optimal distribution of load to plural cache servers even when a fault occurs in any cache server. SOLUTION: A cluster control part distributes a request from terminal equipment corresponding to the loads of cache servers. When requested data (stream data) exist in a stream data storage part, the relevant data are distributed to the terminal equipment by the cache server and when such data to not exist, data distributed from a contents server are distributed to the terminal equipment. In this case, the data distributed from the contents server are double stored in the stream data storage parts of at least two cache servers. Besides, each of cache servers detects the distributing state of the other cache server double storing the data and when the other cache server is disabled in distribution, the distribution of data is continued in place of such a cache server.

Cluster server device

A cluster server apparatus is provided capable of
continuously carrying out data distribution to terminals even if
any cache server is failed, while optimally distributing loads
on a plurality of cache servers. A cluster control unit (21) distributes requests from the
terminals based on the load on each cache server (10 x ). The cache
server (10 x ) distributes, to the terminal (4 y ), requested data
(streaming data) if it is stored in a streaming data storage unit
(14 x ), while distributing data from a content server (30) if it
is not stored therein. Here, the data distributed from the
content server (30) is redundantly stored in the streaming data
storage units (14 x , 14 x+1 ) of two or more cache servers (10 x , 10 x+1 ).
One cache server (10 x ) detects the state of distribution of the
other cache server (10 x+1 , 10 x-1 ) that stores the same data as that
stored in the one cache server (10). If the one cache server (10 x )
becomes unable to carry out distribution, the other cache server
(10 x+1 , 10 x-1 ) continues data distribution instead.

Asai Rieko

Papers

Cluster server apparatus

Cluster server device

Load distribution in a network

Belastungsverteilung in einem Netzwerk