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A CCITT and ISO series of recommendations (ISO/IEC 10021) for message handling. It defines an Interpersonal Messaging System that runs over a store-and-forward Message Transfer System.

Plain language A CCITT and ISO series of recommendations for message handling with an Interpersonal Messaging System.

Used in RFC 987 RFC 1138 RFC 1327

An international standard for message handling systems defined by the CCITT (now ITU), used by many organizations outside the Internet for electronic mail.

Plain language An international standard for message handling systems used outside the Internet.

Used in RFC 1496 RFC 1530 RFC 1664 RFC 2156 RFC 2162 RFC 2163

A standardized distributed directory system defined by ISO that uses a hierarchical tree structure to store information about network resources and users.

Plain language A standardized distributed directory system using a hierarchical tree structure.

Used in RFC 1275 RFC 1277 RFC 1431 RFC 2120

An OSI standard protocol for a distributed, hierarchical directory service defined by CCITT (now ITU) for storing and retrieving information about people and resources.

Plain language An OSI standard protocol for a distributed, hierarchical directory service.

Used in RFC 1107 RFC 1202 RFC 1249 RFC 1274 RFC 1279 RFC 1292 RFC 1309 RFC 1507 RFC 1632 RFC 1727 RFC 1943 RFC 2256 RFC 2654 RFC 3377 RFC 3650

The OSI Directory, a very general naming framework whose entries are organised in a tree and named by attributes such as country, organisation and common name.

Plain language The OSI Directory, a general naming framework with entries organized in a tree.

Used in RFC 1278 RFC 1279 RFC 1430 RFC 1588 RFC 1801 RFC 1803 RFC 1913 RFC 2696 RFC 4514

The standard format for public-key certificates. RFC 5280 profiles version 3 certificates and version 2 CRLs for the Internet.

Plain language The standard format for public-key certificates.

Used in RFC 1422 RFC 1588 RFC 1848 RFC 2116 RFC 2312 RFC 2559 RFC 3039 RFC 3163 RFC 3280 RFC 3335 RFC 3647 RFC 3709 RFC 3739 RFC 4043 RFC 4261 RFC 4334 RFC 4366 RFC 4386 RFC 4398 RFC 4476 RFC 4514 RFC 4519 RFC 4523 RFC 4630 and 42 more

A signed record that binds a public key to an identity, issued by a certificate authority. CMS uses certificates to find the key needed to check a signature or to encrypt to a recipient.

Plain language A signed record binding a public key to an identity, issued by a certificate authority.

Used in RFC 1421 RFC 1430 RFC 1507 RFC 2025 RFC 2218 RFC 2312 RFC 2315 RFC 2316 RFC 2437 RFC 2459 RFC 2510 RFC 2511 RFC 2528 RFC 2560 RFC 2585 RFC 2587 RFC 2660 RFC 2693 RFC 2798 RFC 2801 RFC 2818 RFC 2829 RFC 2830 RFC 2943 and 272 more

Letting graphical programs on a remote machine show their windows on your local screen by tunneling the X11 protocol through SSH channels.

Plain language Tunneling the X11 protocol through SSH to let remote graphical programs show windows locally.

Used in RFC 1096 RFC 4254

The XML Configuration Access Protocol lets clients read and change parts of XML documents stored on a server, using HTTP. Each kind of document is handled by an application usage.

Plain language A protocol letting clients read and change parts of XML documents stored on a server.

Used in RFC 4825 RFC 4826 RFC 5363 RFC 5874 RFC 5875

A standard notation and encoding for describing data structures so that different computers can exchange them in an identical way. NFS messages are described in it.

Plain language A standard notation and encoding for describing data structures for inter-computer exchange.

Used in RFC 1094 RFC 2215 RFC 5531 RFC 5662 RFC 5666 RFC 7531 RFC 7861 RFC 7863 RFC 8166 RFC 8178

The Extensible Markup Language, a text format that nests named elements and attributes to describe structured data.

Plain language The Extensible Markup Language, a text format nesting named elements to describe structured data.

Used in RFC 2801 RFC 3076 RFC 3121 RFC 3236 RFC 3253 RFC 3340 RFC 3341 RFC 3470 RFC 3744 RFC 3920 RFC 4112 RFC 4227 RFC 4480 RFC 4575 RFC 4660 RFC 4662 RFC 4745 RFC 4825 RFC 4826 RFC 4910 RFC 4911 RFC 5070 RFC 5261 RFC 5263 and 21 more

A URI that marks which specification an XML element belongs to, so that elements from different specifications do not clash.

Plain language A URI marking which specification an XML element belongs to.

Used in RFC 2801 RFC 3076 RFC 3470 RFC 3863 RFC 4050 RFC 4287 RFC 4480 RFC 4575 RFC 4662 RFC 4765 RFC 4825 RFC 4854 RFC 4911 RFC 5070 RFC 5139 RFC 5261 RFC 5364 RFC 6110 RFC 6231 RFC 6321 RFC 6351 RFC 6848 RFC 7203 RFC 7950 and 2 more

A formal description of which elements, attributes and values an XML document may contain, used to check whether a document is valid.

Plain language A formal description of which elements, attributes and values an XML document may contain.

Used in RFC 4050 RFC 4480 RFC 4745 RFC 4825 RFC 4826 RFC 4911 RFC 5070 RFC 5139 RFC 5364 RFC 6030 RFC 7970 RFC 8794

A W3C standard for digitally signing XML documents using public-key cryptography, allowing verification of authenticity and integrity.

Used in RFC 6030 RFC 6545 RFC 6931

A container for XML sent in one direction over a connection. XMPP uses two, one in each direction, and each starts with a stream header and ends with a closing tag.

Plain language A container for XML sent in one direction over a connection.

Used in RFC 2376 RFC 2629 RFC 2803 RFC 3106 RFC 3120 RFC 3354 RFC 3920 RFC 4331 RFC 4741 RFC 4767 RFC 4839 RFC 4911 RFC 4913 RFC 4914 RFC 4918 RFC 4991 RFC 5263 RFC 5277 RFC 5388 RFC 5730 RFC 6022 RFC 6110 RFC 6120 RFC 6121 and 9 more

The Extensible Messaging and Presence Protocol: an XML-based protocol for real-time messaging, presence and request-response between clients and servers, and between servers. Defined in RFC 6120.

Plain language An XML-based protocol for real-time messaging, presence and request-response between clients and servers.

Used in RFC 3920 RFC 3921 RFC 3922 RFC 3923 RFC 4479 RFC 4622 RFC 4770 RFC 4979 RFC 5122 RFC 5435 RFC 5437 RFC 6120 RFC 6121 RFC 6122 RFC 6132 RFC 6366 RFC 6473 RFC 6885 RFC 7081 RFC 7165 RFC 7247 RFC 7248 RFC 7259 RFC 7395 and 13 more

A bitwise operation that combines two binary values; it outputs 1 when the inputs differ and 0 when they match. XOR has the property that A XOR B XOR B equals A, making it useful for error correction.

Plain language A bitwise operation outputting 1 when inputs differ and 0 when they match.

Used in RFC 2733 RFC 4418 RFC 4503 RFC 9058

A query language that picks out nodes from an XML document by describing a path through its tree structure.

Plain language A query language picking out nodes from an XML document by describing a path through its structure.

Used in RFC 4660 RFC 4661 RFC 5261 RFC 5717 RFC 6020 RFC 6110 RFC 7950 RFC 8407 RFC 8639

A string that selects nodes within an XML document using a path-like syntax, for example doc/elem[@a='foo'] selects elem elements with an attribute a equal to 'foo'.

Plain language A string selecting nodes within an XML document using a path-like syntax.

Used in RFC 3653 RFC 7351

An encoding that lets any octet appear in an SMTP parameter value by writing awkward characters as a plus sign followed by two upper-case hexadecimal digits.

Used in RFC 1894 RFC 3461