10 H

handle: (1) Any token that can be used to identify and access an object such as a device, file, or a window.

(2) A 32-bit numerical ID that uniquely identifies a resource or a channel. Handles are allocated by the server and communicated to the client via resource or channel creation messages.

(3) A recipient of a message.

(4) A token that can be used to identify and access cursors, chapters, and bookmarks.

handle array: An array of object handles that are sent to and received from a server as part of a remote procedure call (RPC) accompanying ROP request buffers and ROP response buffers, respectively. Also referred to as a Server object handle table or an HSOT table.

hard delete: A process that removes an item permanently from the system. If an item is hard deleted, a server does not retain a back-up copy of the item and a client cannot access or restore the item. See also soft delete.

hash: (1) A fixed-size result that is obtained by applying a one-way mathematical function, which is sometimes referred to as a hash algorithm, to an arbitrary amount of data. If the input data changes, the hash also changes. The hash can be used in many operations, including authentication (2) and digital signing.

(2) A hash, such as SHA-1, on the content or content block.

(3) A term that refers to either a hash function, the value computed by such a function, or the act of computing such a value.

hash list: A list of hashes that include the blockhashes and the contenthash.

header: (1) A line, or lines, of content in the top margin area of a page in a document or a slide in a presentation. A header typically contains elements such as the title of the chapter, the title of the document, a page number, or the name of the author.

(2) A name-value pair that supplies structured data in an Internet email message or MIME entity.

(3) The structure at the beginning of a compound file.

header field: (1) A component of a Session Initiation Protocol (SIP) message header, as described in [RFC3261].

(2) As specified in section 4.2 of [RFC2616].

header message object: A Message object that contains partial information about a message on a server, such as an identifier for the message, the display names of the recipients and the sender, the subject of the message, and the delivery time of the message. It allows a client to display enough information about a message to let a user choose whether to download the message.

header row: (1) A row in a table, typically the first row, that contains labels for columns (2) in the table.

(2) A row at the beginning of a category (5) that does not represent data in the Table object, but provides information about a grouping.

Help file: A file that contains the documentation for a specific product or technology.

hierarchy synchronization: The process of keeping synchronized versions of folder hierarchies and their properties on a client and server.

hierarchy table: A Table object whose rows represent the Folder objects that are contained in another Folder object.

host: (1) A general-purpose computer that is networking capable.

(2) In DirectPlay, the computer responsible for responding to DirectPlay game session enumeration requests and maintaining the master copy of all the player and group lists for the game. One computer is designated as the host of the DirectPlay game session. All other participants in the DirectPlay game session are called peers. However, in peer-to-peer mode the name table entry representing the host of the session is also marked as a peer.

(3) A subcomponent of the naming authority in a URIscheme, as defined in [RFC3986] section 3.2.2.

(4) An interface between an application runspace and a user capable of responding to the host method calls specified in [MS-PSRP] section 2.2.3.17.

(5) The machine with the desktop or applications that are being shared with the other participants.

hosted cache: A centralized cache comprised of blocks added by peers.

Hypertext Markup Language (HTML): An application of the Standard Generalized Markup Language (SGML) that uses tags to mark elements in a document, as described in [HTML].

Hypertext Transfer Protocol (HTTP): An application-level protocol for distributed, collaborative, hypermedia information systems (text, graphic images, sound, video, and other multimedia files) on the World Wide Web.

Hypertext Transfer Protocol over Secure Sockets Layer (HTTPS): An extension of HTTP that securely encrypts and decrypts webpage requests.