rfc1028.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

   A variable such that the initial portion of its name is represented
   symbolically as "_GW_pr_in_addr_scope" and numerically as:

                 01 04 01 01 02

   has an octet string value that names the network interface with which
   the IP interface identified by the remainder of the name for said
   variable is associated.

6.5.2.  Exterior Gateway Protocol (EGP) Variables

   This section describes variables that represent information related
   to protocols and mechanisms of the EGP protocol [4].

6.5.2.1.  The _GW_pr_in_egp_core Variable

   A variable such that the initial portion of its name is represented
   symbolically as "_GW_pr_in_egp_core" and numerically as:

                 01 04 01 03 01

   has an integer value that characterizes the associated gateway with
   respect to the set of INTERNET core gateways.  A nonzero value
   indicates that the associated gateway is part of the INTERNET core.

6.5.2.2.  The _GW_pr_in_egp_as Variable Class

   A variable such that the initial portion of its name is represented
   symbolically as "_GW_pr_in_egp_as" and numerically as:

                 01 04 01 03 02

   has an integer value that literally identifies an Autonomous System
   to which this gateway belongs.

6.5.2.3.  The EGP Neighbor Variable Classes

   This section describes a related set of variables that represent
   attributes of "neighbors" with which the gateway may be associated by
   EGP.  Each such EGP neighbor is uniquely identified by an octet



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   string. The convention by which names are assigned to EGP neighbors
   of a gateway is implementation-specific.

6.5.2.3.1.  The _GW_pr_in_egp_neighbor_addr Variable Class

   A variable such that the initial portion of its name is represented
   symbolically as "_GW_pr_in_egp_neighbor_addr" and numerically as:

                 01 04 01 03 03 01

   has an octet string value that literally represents the 32-bit
   Internet address for the EGP neighbor identified by the remainder of
   the name for said variable.

6.5.2.3.2.  The _GW_pr_in_egp_neighbor_state Variable Class

   A variable such that the initial portion of its name is represented
   symbolically as "_GW_pr_in_egp_neighbor_state" and numerically as:

                 01 04 01 03 03 02

   has an octet string value that represents the EGP protocol state of
   the gateway with respect to the EGP neighbor identified by the
   remainder of the name for said variable. The meaningful values for
   such a variable are: "IDLE," "ACQUISITION," "DOWN," "UP," and
   "CEASE."

6.5.2.4.  The _GW_pr_in_egp_errors Variable

   The variable such that the initial portion of its name is represented
   symbolically as "_GW_pr_in_egp_errors" and numerically as:

                 01 04 01 03 05

   has an integer value that represents the number of EGP protocol
   errors.

6.5.3.  Routing Variable Classes

   This section describes a related set of variables that represent
   attributes of the the IP routes by which a gateway directs packets to
   various destinations on the Internet.  Each such route is uniquely
   identified by an octet string that is the concatenation of the
   literal 32-bit value of the Internet address for the destination of
   said route together with an implementation-specific octet string.
   The convention by which names are assigned to the Internet routes for
   a gateway is in all other respects implementation-specific.




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6.5.3.1.  The _GW_pr_in_rt_gateway Variable Class

   A variable such that the initial portion of its name is represented
   symbolically as "_GW_pr_in_rt_gateway" and numerically as:

                 01 04 01 02 01

   has an octet string value that literally represents the 32-bit
   Internet address of the next gateway to which traffic is directed by
   the route identified by the remainder of the name for said variable.

6.5.3.2.  The _GW_pr_in_rt_type Variable Class

   A variable such that the initial portion of its name is represented
   symbolically as "_GW_pr_in_rt_type" and numerically as:

                 01 04 01 02 02

   has an integer value that represents the type of the route identified
   by the remainder of the name for said variable.  Route types are
   identified according to the conventions described in Appendix 3.

6.5.3.3.  The _GW_pr_in_rt_how-learned Variable Class

   A variable such that the initial portion of its name is represented
   symbolically as "_GW_pr_in_rt_how-learned" and numerically as:

                   01 04 01 02 03

   has an octet string value that represents the source of the
   information from which the route identified by the remainder of the
   name for said variable is generated. The meaningful values of such a
   variable are: "STATIC," "EGP," and "RIP."

6.5.3.4.  The _GW_pr_in_rt_metric0 Variable Class

   A variable such that the initial portion of its name is represented
   symbolically as "_GW_pr_in_rt_metric0" and numerically as:

                 01 04 01 02 04

   has an integer value that represents the quality (in terms of cost,
   distance from the ultimate destination, or other metric) of the route
   identified by the remainder of the name for said variable.

6.5.3.5.  The _GW_pr_in_rt_metric1 Variable Class

   A variable such that the initial portion of its name is represented



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   symbolically as "_GW_pr_in_rt_metric1" and numerically as:

                 01 04 01 02 05

   has an integer value that represents the quality (in terms of cost,
   distance from the ultimate destination, or other metric) of the route
   identified by the remainder of the name for said variable.

6.6.  DECnet Protocol Variables

   This section describes variables that represent information related
   to protocols and mechanisms of the DEC Digital Network Architecture.
   DEC and DECnet are registered trademarks of Digital Equipment
   Corporation.

6.7.  XNS Protocol Variables

   This section describes variables that represent information related
   to protocols and mechanisms of the Xerox Network System.  Xerox
   Network System and XNS are registered trademarks of the XEROX
   Corporation.

7.  Implementation-Specific Variables

   Additional variables that may be presented for inspection or
   manipulation by particular protocol entity implementations are
   described in Appendices to this document.

8.  References

   [1]  CCITT, "Message Handling Systems: Presentation Transfer
        Syntax and Notation", Recommendation X.409, 1984.


   [2]  Postel, J., "User Datagram Protocol", RFC-768,
        USC/Information Sciences Institute, August 1980.

   [3]  Postel, J., "Internet Protocol", RFC-760, USC/Information
        Sciences Institute, January 1980.

   [4]  Rosen, E., "Exterior Gateway Protocol", RFC-827, Bolt
        Beranek and Newman, October 1982.

9.  Appendix 1: Network Type Representation

Numeric representations for various types of networks are presented
   below:




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                         Value   Network Type
                         ====================
                         0       Unspecified
                         1       IEEE 802.3 MAC
                         2       IEEE 802.4 MAC
                         3       IEEE 802.5 MAC
                         4       Ethernet
                         5       ProNET-80
                         6       ProNET-10
                         7       FDDI
                         8       X.25
                         9       Point-to-Point Serial
                         10      Proprietary Point-to-Point Serial
                         11      ARPA 1822 HDH
                         12      ARPA 1822
                         13      AppleTalk
                         14      StarLAN

10.  Appendix 2: Network Status Representation

Numeric representations for network status are presented below.

                         Value   Network Status
                         ======================
                         0       Interface Operating Normally
                         1       Interface Not Present
                         2       Interface Disabled
                         3       Interface Down
                         4       Interface Attempting Link


11.  Appendix 3: Route Type Representation

Numeric representations for route types are presented below.

                         Value   Route Type
                         ==================
                         0       Route to Nowhere -- ignored
                         1       Route to Directly Connected Network
                         2       Route to a Remote Host
                         3       Route to a Remote Network
                         4       Route to a Sub-Network

12.  Appendix 4: Initial Implementation Strategy

   The initial objective of implementing the protocol specified in this
   document is to provide a mechanism for monitoring Internet gateways.
   While the protocol design makes some provision for gateway management



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   functions as well, this aspect of the design is not fully developed
   and needs further refinement before a generally useful implementation
   could be produced.  Accordingly, initial implementations will not
   generate or respond to the optional Set Request message type.

   The protocol defined here may be subsequently refined based upon
   experience with early implementations or upon further study of the
   problem of gateway management.  Moreover, it may be superceded by
   other proposals in the area of gateway monitoring and control.

   Implementations of the authentication protocol specified in this
   document are likely to evolve in response to the particular security
   and privacy needs of its users.  While, in general, the association
   between particular half-sessions of the authentication protocol and
   the described triplets of functions is specific to an implementation
   and beyond the scope of this document, the desire for immediate
   interoperability among initial implementations of this protocol is
   best served by the temporary adoption of a common authentication
   scheme.  Accordingly, initial implementations will associate with
   every possible half-session a triplet of functions that realizes a
   trivial authentication mechanism:

   (1)  The authentication function is defined to have the value
        TRUE over the entire domain of authentication protocol
        messages.

   (2)  The message interpretation function is defined to be the
        identity function.

   (3)  The message representation function is defined to be the
        identity function.

   Because this initial posture with respect to authentication is not
   likely to remain acceptable indefinitely, implementors are urged to
   adopt designs that isolate authentication mechanism as much as
   possible from other components of the implementation.

13.  Appendix 5: Routing Information Propagation Variables

   This section describes a set of related variables that characterize
   the sources and destinations of routing information propagated by
   various routing protocols. These variables have meaning only for
   those routing protocol implementations that afford greater
   flexibility in propagating routing information than is required by
   the various routing protocol specifications.

   Each IP interface afforded by the configuration of the gateway over
   which routing information may propagate via a routing protocol