Compression scheme used by the Replica Location Service (RLS) that is intended to reduce the size of soft state updates between Local Replica Catalogs (LRCs) and Replica Location Index (RLI) servers. A Bloom filter is a bit map that summarizes the contents of a Local Replica Catalog (LRC). An LRC constructs the bit map by applying a series of hash functions to each logical name registered in the LRC and setting the corresponding bits.

A public key plus information about the certificate owner bound together by the digital signature of a CA. In the case of a CA certificate, the certificate is self signed, i.e. it was signed using its own private key.

A job scheduler mechanism supported by GRAM. See http://www.cs.wisc.edu/condor/ for more information.

MODE E is a critical GridFTP components because it allows for out of order reception of data. This in turn, means we can send the data down multiple paths and do not need to worry if one of the paths is slower than the others and the data arrives out of order. This enables parallelism and striping within GridFTP. In MODE E, a series of “blocks” are sent over the data channel. Each block consists of:

Note that since the offset and length are included in the block, out of order reception is possible, as long as the receiving side can handle it, either via something like a seek on a file, or via some application level buffering and ordering logic that will wait for the out of order blocks. [TODO: LINK TO GRAPHIC]

A file containing entries mapping certificate subjects to local user names. This file can also serve as a access control list for GSI enabled services and is typically found in /etc/grid-security/grid-mapfile. For more information see the [Gridmap file in Pre-WS Authorization & Authentication Developer's Guide ("Environmental Variables" section)].

An EEC belonging to a host. When using GSI this certificate is typically stored in /etc/grid-security/hostcert.pem. For more information on possible host certificate locations see the [Pre-WS Authentication & Authorization Developer's Guide ("Environmental Variables" section) on Credentials].

[this term does not appear anywhere in the gridftp docs] This protocol is still under development. It is intended to address a number of the deficiencies found in MODE E. For instance, it will have explicit negotiation for use of a data channel, thus removing the race condition and the requirement for the sender to be the connector. This will help with firewall traversal. A method will be added to allow the filename to be provided prior to the data channel connection being established to help large data farms better allocate resources. Other additions under consideration include block checksumming, resends of blocks that fail checksums, and inclusion of a transfer ID to allow pipelining and de-multiplexing of commands.

Term used to describe a GRAM4 job for GT4.

See the term scheduler.

Stores mappings between logical names for data items and the target names (often the physical locations) of replicas of those items. Clients query the LRC to discover replicas associated with a logical name. Also may associate attributes with logical or target names. Each LRC periodically sends information about its logical name mappings to one or more RLIs.

See also RLI.

A unique identifier for the contents of a file.

A job scheduler mechanism supported by GRAM.

For more information, see http://www.platform.com/Products/Platform.LSF.Family/Platform.LSF/.

A job that is itself composed of several executable jobs; these are processed by the MMJS subjob.

See also MMJS subjob.

When speaking about GridFTP transfers, parallelism refers to having multiple TCP connections between a single pair of network endpoints. This is used to improve performance of transfers on connections with light to moderate packet loss.

A job scheduler mechanism supported by GRAM. For more information, see http://www.openpbs.org.

The address or the location of a copy of a file on a storage system.

The private part of a key pair. Depending on the type of certificate the key corresponds to it may typically be found in $HOME/.globus/userkey.pem (for user certificates), /etc/grid-security/hostkey.pem (for host certificates) or /etc/grid-security/<service>/<service>key.pem (for service certificates).

For more information on possible private key locations see [Credentials in the Pre-WS Authentication & Authorization Developer's Guide ("Environmental Variables" section)].

A short lived certificate issued using a EEC. A proxy certificate typically has the same effective subject as the EEC that issued it and can thus be used in its place. GSI uses proxy certificates for single sign on and delegation of rights to other entities.

For more information about types of proxy certificates and their compatibility in different versions of GT, see http://dev.globus.org/wiki/Security/ProxyCertTypes.

Collects information about the logical name mappings stored in one or more Local Replica Catalogs (LRCs) and answers queries about those mappings. Each RLI periodically receives updates from one or more LRCs that summarize their contents.

Term used to describe a GRAM job for GT2 and GT3. (Note: This is not the same as RLS - the Replica Location Service)

Descriptive information that may be associated with a logical or target name mapping registered in a Local Replica Catalog (LRC). Clients can query the LRC to discover logical names or target names that have specified RLS attributes.

The compliment to the client is the server. Its defining characteristic is that it receives commands and sends responses to those commands. Since it is a server or service, and it receives commands, it must be listening on a port somewhere to receive the commands. Both FTP and GridFTP have IANA registered ports. For FTP it is port 21, for GridFTP it is port 2811. This is normally handled via inetd or xinetd on Unix variants. However, it is also possible to implement a daemon that listens on the specified port. This is described more fully in in the [Architecture section of the GridFTP Developer's Guide].

A EEC for a specific service (e.g. FTP or LDAP). When using GSI this certificate is typically stored in /etc/grid-security/<service>/<service>cert.pem. For more information on possible service certificate locations, see [Credentials in the Pre-WS Authentication & Authorization Developer's Guide ("Environmental Variables" section)].

The only mode normally implemented for FTP is MODE S. This is simply sending each byte, one after another over the socket in order, with no application level framing of any kind. This is the default and is what a standard FTP server will use. This is also the default for GridFTP.

In the simplest terms, a third party transfer moves a file between two GridFTP servers.

The following is a more detailed, programmatic description [should be in documentation somewhere-key concepts?].

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.

Uses transport-level security (TLS) mechanisms.

Identifier that is immutable and unique across time and space.

A EEC belonging to a user. When using GSI, this certificate is typically stored in $HOME/.globus/usercert.pem. For more information on possible user certificate locations, see [Credentials in the Pre-WS A&A Developer's Guide ("Environmental Variables" section)].

The WS-Addressing specification defines transport-neutral mechanisms to address web services and messages. Specifically, it defines XML elements to identify web service endpoints and to secure end-to-end endpoint identification in messages. See the W3C WS Addressing Working Group for details.

Extensible Markup Language (XML) is standard, flexible, and extensible data format used for web services. See the W3C XML site for details.