Gain access to thousands of new definitions only available to registered users.
Parallel Computing Definitions About: Cloud Computing Amazon Web Services Amazon EC2 Amazon S3 Grid Computing
Parent Topic Definitions About: Technology
A class of enterprise application which usually exhibits some of the following attributes -
is 'the Internet', or 'the Grid', or 'Utility Computing' or 'the Information Superhighway', or any other buzz word you can think of for the latest re-branding of 'the Web' (if you are really cool call it 'Web 3.0'). However, this time around 'the Cloud' is associated with very large data centres that can provide computing resources on demand for granular costing (keep your meme cache on for some kind of 'green cloud' coming soon). What the Cloud really means is less financial responsibility for the developer who is usually thinking about code and not financial predictions or growth rates. In short, as your data or users increase the number of server boxes you need to keep the users clicks reacting fast can be purchased as you grow. There are other advantages to the Cloud but for the sake of bluntness 'the Cloud' in this report is a way for developers to get rid of the responsibility and time needed for predicting growth, aka "the cloud means no VC!". And please keep in mind that 'growth' is key to what repositories must do if they are to be successful in the Cloud.
a stack is made up of various computing components which provide different functionality. Typically a stack will include (but is not limited to): Operating System (OS) + Web Server (WS) + Database (DB) + Software (SW) = base components for a service. Common platform stacks that are put onto "blank servers" are things like the LAMP stack: Linux OS, Apache WS, MySQL DB and a Programming Language (usually Perl, Python or PHP) based SW. The various kinds of components in a stack will define what kind of service it is.
In the simplest terms, a third party transfer moves a file between two GridFTP servers.
The following is a more detailed, programmatic description.
In a third party transfer, there are three entities involved. The client, who will only orchestrate, but not actually take place in the data transfer, and two servers one of which will be sending data to the other. This scenario is common in Grid applications where you may wish to stage data from a data store somewhere to a supercomputer you have reserved. The commands are quite similar to the client/server transfer. However, now the client must establish two control channels, one to each server. He will then choose one to listen, and send it the PASV command. When it responds with the IP/port it is listening on, the client will send that IP/port as part of the PORT command to the other server. This will cause the second server to connect to the first server, rather than the client. To initiate the actual movement of the data, the client then sends the RETR "filename" command to the server that will read from disk and write to the network (the "sending" server) and will send the STOR "filename" command to the other server which will read from the network and write to the disk (the "receiving" server).
See Also client/server transfer.
Transport Layer Security is a protocol that provides privacy and data integrity between two communicating applications, layered on top of TCP/IP.
An aggregator service (in WS MDS) that collects information and compares that data against a set of conditions defined in a configuration file. When a condition is met, or triggered, the specified action takes place (for example, an email is sent to a system administrator when the disk space on a server reaches a threshold).
The directory containing the CA certificates and signing policy files of the CAs trusted by GSI. Typically this directory is
/etc/grid-security/certificates. For more information see this.