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These consist of the protocols that define the format and structure of data and information that is either accessed from a directory or exchanged through communications.

  • Border Gateway Protocol (BGP)

    Refers to a routing protocol used to exchange routing information between routers on a network, enabling more efficient routing of data. BGP is part of RFC 1771.

  • Directory Services (X.500)

    This is a network service that discovers and identifies resources on a network and makes them accessible to users and applications. The resources include users, e-mail addresses, computers, mapped drives, shared folders, and peripherals such as printers and PDA docking stations. Users and computers access these resources without the needing to know how or where the resources are connected.

  • Domain Name System (DNS)

    A protocol used for translating domain names (i.e. to their respective IP addresses. DNS is collectively a network of devices which store query results. As one DNS server or device cannot provide the translated IP address, it queries other DNS devices. This process is invisible to the user.

  • Dynamic Host Configuration Protocol (DHCP)

    A protocol for assigning dynamic IP addresses to devices on a network. A device can receive a different IP address at every connection. Dynamic addressing provides reduced network administration over deploying and connecting user and peripheral devices.

  • Extended Simple Mail Transfer Protocol (ESMTP)

    ESMTP allows new service extensions to SMTP to be defined and registered with Internet Assigned Numbers Authority (IANA).

  • H.323

    H.323 addresses Video (Audiovisual) communication on Local Area Networks, including Corporate Intranets and packet-switched networks generally.

  • Internet Message Access Protocol / Post Office Protocol (IMAP / POP3)

    IMAP4rev1 allows a client to access and manipulate electronic mail messages on a server. IMAP4rev1 permits manipulation of remote message folders, called “mailboxes”, in a way that is functionally equivalent to local mailboxes. IMAP4rev1 also provides the capability for an offline client to resynchronize with the server. POP3 is the most commonly used protocol for retrieving e-mail from a mail host.

  • Lightweight Directory Access Protocol (LDAP)

    Lightweight Directory Access Protocol (LDAP) is a subset of X.500 designed to run directly over the TCP/IP stack. LDAP is, like X.500, both an information model and a protocol for querying and manipulating it. LDAPv3 is an update developed in the IETF (Internet Engineering Task Force), which address the limitations found during deployment of the previous version of LDAP.

  • Multipurpose Internet Mail Extensions (MIME)

    MIME extends the format of Internet mail to allow non-US- American Standard Code for Information Interchange (ASCII) textual messages, non-textual messages, multi-part message bodies, and non-US-ASCII information in message headers. MIME support allows compliant email clients and servers to accurately communicate embedded information to internal and external users.

  • Simple Mail Transfer Protocol (SMTP)

    SMTP facilitates transfer of electronic-mail messages. It specifies how two systems are to interact, and the messages format used to control the transfer of electronic mail.

  • Simple Network Management Protocol (SNMP)

    SNMP Eliminates several of the security vulnerabilities in earlier version.

  • T.120

    T.120 contains a series of communication and application protocols and services that provide support for real-time, multipoint data communications. These multipoint facilities are important building blocks for collaborative applications, including desktop data conferencing, and multi-user applications.

  • X.400

    An ISO and ITU standard for e-mail message addressing and transporting. X.400 supports Ethernet, X.25, TCP/IP and dial-up transport methods.