F <- 4. Definitions -> H


G

   $ gateway
      (I) An intermediate system (interface, relay) that attaches to two
      (or more) computer networks that have similar functions but
      dissimilar implementations and that enables either one-way or two-
      way communication between the networks. (See: bridge, firewall,
      guard, internetwork, proxy server, router, and subnetwork.)
      Tutorial: The networks may differ in any of several aspects,
      including protocols and security mechanisms. When two computer
      networks differ in the protocol by which they offer service to
      hosts, a gateway may translate one protocol into the other or
      otherwise facilitate interoperation of hosts (see: Internet
      Protocol). In theory, gateways between computer networks are
      conceivable at any OSIRM layer. In practice, they usually operate


Shirey                       Informational                    [Page 134]
RFC 4949         Internet Security Glossary, Version 2       August 2007

      at OSIRM Layer 2 (see: bridge), 3 (see: router), or 7 (see: proxy
      server).
   $ GCA
      (O) See: geopolitical certificate authority.
   $ GDOI
      (O) See: Group Domain of Interpretation.
   $ GeldKarte
      (O) A smartcard-based, electronic money system that is maintained
      by the German banking industry, incorporates cryptography, and can
      be used to make payments via the Internet. (See: IOTP.)
   $ GeneralizedTime
      (N) The ASN.1 data type "GeneralizedTime" (ISO 8601) contains a
      calendar date (YYYYMMDD) and a time of day, which is either (a)
      the local time, (b) the Coordinated Universal Time, or (c) both
      the local time and an offset that enables Coordinated Universal
      Time to be calculated. (See: Coordinated Universal Time. Compare:
      UTCTime.)
   $ Generic Security Service Application Program Interface (GSS-API)
      (I) An Internet Standard protocol [R2743] that specifies calling
      conventions by which an application (typically another
      communication protocol) can obtain authentication, integrity, and
      confidentiality security services independently of the underlying
      security mechanisms and technologies, thus enabling the
      application source code to be ported to different environments.
      (Compare: EAP, SASL.)
      Tutorial: "A GSS-API caller accepts tokens provided to it by its
      local GSS-API implementation and transfers the tokens to a peer on
      a remote system; that peer passes the received tokens to its local
      GSS-API implementation for processing. The security services
      available through GSS-API in this fashion are implementable (and
      have been implemented) over a range of underlying mechanisms based
      on [symmetric] and [asymmetric cryptography]." [R2743]
   $ geopolitical certificate authority (GCA)
      (O) /SET/ In a SET certification hierarchy, an optional level that
      is certified by a BCA and that may certify cardholder CAs,
      merchant CAs, and payment gateway CAs. Using GCAs enables a brand
      to distribute responsibility for managing certificates to
      geographic or political regions, so that brand policies can vary
      between regions as needed.



Shirey                       Informational                    [Page 135]
RFC 4949         Internet Security Glossary, Version 2       August 2007

   $ GIG
      (O) See: Global Information Grid.
   $ Global Information Grid (GIG)
      (O) /U.S. DoD/ The GIG is "a globally interconnected, end-to-end
      set of information capabilities, associated processes and
      personnel for collecting, processing, storing, disseminating, and
      managing information on demand to war fighters, policy makers, and
      support personnel." [IATF] Usage: Formerly referred to as the DII.
   $ good engineering practice(s)
      (N) A term used to specify or characterize design, implementation,
      installation, or operating practices for an information system,
      when a more explicit specification is not possible. Generally
      understood to refer to the state of the engineering art for
      commercial systems that have problems and solutions equivalent to
      the system in question.
   $ granularity
      1. (N) /access control/ Relative fineness to which an access
      control mechanism can be adjusted.
      2. (N) /data security/ "The size of the smallest protectable unit
      of information" in a trusted system. [Huff]
   $ Green Book
      (D) /slang/ Synonym for "Defense Password Management Guideline"
      [CSC2].
      Deprecated Term: Except as an explanatory appositive, IDOCs SHOULD
      NOT use this term, regardless of the associated definition.
      Instead, use the full proper name of the document or, in
      subsequent references, a conventional abbreviation. (See: Rainbow
      Series.)
      Deprecated Usage: To improve international comprehensibility of
      Internet Standards and the Internet Standards Process, IDOCs
      SHOULD NOT use "cute" synonyms. No matter how clearly understood
      or popular a nickname may be in one community, it is likely to
      cause confusion or offense in others. For example, several other
      information system standards also are called "the Green Book"; the
      following are some examples:
      -  Each volume of 1992 ITU-T (known at that time as CCITT)
         standards.
      -  "PostScript Language Program Design", Adobe Systems, Addison-
         Wesley, 1988.
      -  IEEE 1003.1 POSIX Operating Systems Interface.


Shirey                       Informational                    [Page 136]
RFC 4949         Internet Security Glossary, Version 2       August 2007

      -  "Smalltalk-80: Bits of History, Words of Advice", Glenn
         Krasner, Addison-Wesley, 1983.
      -  "X/Open Compatibility Guide".
      -  A particular CD-ROM format developed by Phillips.
   $ Group Domain of Interpretation (GDOI)
      (I) An ISAKMP/IKE domain of interpretation for group key
      management; i.e., a phase 2 protocol in ISAKMP. [R3547] (See:
      secure multicast.)
      Tutorial: In this group key management model that extends the
      ISAKMP standard, the protocol is run between a group member and a
      "group controller/key server", which establishes security
      associations [R4301] among authorized group members. The GDOI
      protocol is itself protected by an ISAKMP phase 1 association.
      For example, multicast applications may use ESP to protect their
      data traffic. GDOI carries the needed security association
      parameters for ESP. In this way, GDOI supports multicast ESP with
      group authentication of ESP packets using a shared, group key.
   $ group identity
      (I) See: secondary definition under "identity".
   $ group security association
      (I) "A bundling of [security associations] (SAs) that together
      define how a group communicates securely. The [group SA] may
      include a registration protocol SA, a rekey protocol SA, and one
      or more data security protocol SAs." [R3740]
   $ GSS-API
      (I) See: Generic Security Service Application Program Interface.
   $ guard
      (I) A computer system that (a) acts as gateway between two
      information systems operating under different security policies
      and (b) is trusted to mediate information data transfers between
      the two. (See: controlled interface, cross-domain solution,
      domain, filter. Compare: firewall.)
      Usage: Frequently understood to mean that one system is operating
      at a higher security level than the other, and that the gateway's
      purpose is to prevent unauthorized disclosure of data from the
      higher system to the lower. However, the purpose might also be to
      protect the data integrity, availability, or general system
      integrity of one system from threats posed by connecting to the
      other system. The mediation may be entirely automated or may
      involve "reliable human review".

Shirey                       Informational                    [Page 137]
RFC 4949         Internet Security Glossary, Version 2       August 2007

   $ guest login
      (I) See: anonymous login.
   $ GULS
      (I) Generic Upper Layer Security service element (ISO 11586), a
      five-part standard for the exchange of security information and
      security-transformation functions that protect confidentiality and
      integrity of application data.
   $ Gypsy verification environment
      (O) A methodology, language, and integrated set of software tools
      developed at the University of Texas for specifying, coding, and
      verifying software to produce correct and reliable programs.
      [Cheh]

F <- 4. Definitions -> H