Movatterモバイル変換

Network Working Group                                         W. SimpsonRequest for Comments: 2153                                    DayDreamerUpdates: RFCs1661,1962                                        May 1997Category: InformationalPPP Vendor ExtensionsStatus of this Memo   This document provides information for the Internet community.  It   does not specify an Internet standard of any kind.  Distribution of   this memo is unlimited.Abstract   The Point-to-Point Protocol (PPP) [1] provides a standard method for   transporting multi-protocol datagrams over point-to-point links.  PPP   defines an extensible Link Control Protocol (LCP) for establishing,   configuring, and testing the data-link connection; and a family of   Network Control Protocols (NCPs) for establishing and configuring   different network-layer protocols.   This document defines a general mechanism for proprietary vendor   extensions.Simpson                      Informational                      [Page i]

RFC 2153                 PPP vendor extensions                  May 1997                           Table of Contents1.     Control Packets .......................................11.1       Vendor Specific Packet ..........................12.     Configuration Options .................................32.1       Vendor-Specific Option ..........................33.     Organizationally Unique Identifiers ...................4     SECURITY CONSIDERATIONS ......................................5     REFERENCES ...................................................5     CONTACTS .....................................................6Simpson                      Informational                     [Page ii]

RFC 2153                 PPP vendor extensions                  May 19971.  Control Packets   The Packet format and basic facilities are already defined for LCP   [1] and related NCPs.   Up-to-date values of the LCP Code field are specified in the most   recent "Assigned Numbers" [2].  This document concerns the following   values:       0      Vendor Specific1.1.  Vendor Specific Packet   Description      Some implementors might not need nor want to publish their      proprietary algorithms and attributes.  This mechanism is      available to specify these without encumbering the IANA with      proprietary number requests.      Vendor Specific packets MAY be sent at any time, including before      LCP has reached the Opened state.      The sender transmits a LCP or NCP packet with the Code field set      to 0 (Vendor Specific), the Identifier field set, the local      Magic-Number (if any) inserted, the OUI and Kind fields set, and      the Value(s) field filled with any desired data, but not exceeding      the default MRU minus twelve.      Receipt of a Vendor Specific packet causes the RXR or RUC event.      The response to the Vendor Specific packet is vender specific.      Receipt of a Code-Reject for the packet SHOULD generate the RXJ+      (permitted) event.   Rationale:      This is defined as general feature of all PPP Control Protocols,      to avoid future conflicts in vendor secretly self-assigned Code      numbers.   A summary of the Vendor Specific packet format is shown below.  The   fields are transmitted from left to right.Simpson                      Informational                      [Page 1]

RFC 2153                 PPP vendor extensions                  May 1997   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   |     Code      |  Identifier   |            Length             |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   |                         Magic-Number                          |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   |                      OUI                      |     Kind      |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   |    Value(s) ...   +-+-+-+-+-+-+-+-+   Code       0 for Vendor Specific   Identifier      The Identifier field MUST be changed for each Vendor Specific      packet sent.   Length      >= 12      When the Length is twelve, no Value(s) field is present.   Magic-Number      The Magic-Number field is four octets and aids in detecting links      that are in the looped-back condition.  Until the Magic-Number      Configuration Option has been successfully negotiated, the Magic-      Number MUST be transmitted as zero.  See the Magic-Number      Configuration Option for further explanation.   OUI      three octets.  The vendor's Organizationally Unique Identifier.      The bits within the octet are in canonical order, and the most      significant octet is transmitted first.   Kind      one octet.  Indicates a sub-type for the OUI.  There is no      standardization for this field.  Each OUI implements its own      values.      The Kind field may be extended by the vendor to include zero or      more octets of the Value(s) field.Simpson                      Informational                      [Page 2]

RFC 2153                 PPP vendor extensions                  May 1997   Value(s)      Zero or more octets.  The details are implementation specific.2.  Configuration Options   The Configuration Option format and basic options are already defined   for LCP [1].   Up-to-date values of the LCP Option Type field are specified in the   most recent "Assigned Numbers" [2].  This document concerns the   following values:       0      Vendor-Specific2.1.  Vendor-Specific Option   Description      Some implementors might not need nor want to publish their      proprietary algorithms and attributes.  This mechanism is      available to specify these without encumbering the IANA with      proprietary number requests.      Before accepting this option, the implementation must verify that      the Organizationally Unique Identifier and Kind specify a known      mechanism, and that any vendor specific negotiation values are      fully understood.   Rationale:      This is defined as general feature of all PPP Control Protocols,      to avoid future conflicts in vendor secretly self-assigned Type      numbers.   A summary of the Vendor-Specific Configuration Option format is shown   below.  The fields are transmitted from left to right.   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   |     Type      |    Length     |              OUI   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+          ...      |     Kind      |  Value(s) ...   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-Simpson                      Informational                      [Page 3]

RFC 2153                 PPP vendor extensions                  May 1997   Type       0   Length      >= 6      When the Length is six, no Value(s) field is present.   OUI      three octets.  The vendor's Organizationally Unique Identifier.      The bits within the octet are in canonical order, and the most      significant octet is transmitted first.   Kind      one octet.  Indicates a sub-type for the OUI.  There is no      standardization for this field.  Each OUI implements its own      values.      The Kind field may be extended by the vendor to include zero or      more octets of the Value(s) field.   Value(s)      Zero or more octets.  The details are implementation specific.3.  Organizationally Unique Identifiers   The three-octet Organizationally Unique Identifier (OUI) identifies   an organization that administers the meaning of the message.  This   OUI is based on IEEE 802 vendor assignments.   IEEE contact details for assignment of an OUI are given in [RFC-   1700].  Vendors that desire to use their IEEE 802 OUI for PPP Vendor   Extensions should also register the OUI with IANA.   In the alternative, a vendor that does not otherwise need an IEEE   assigned OUI can request a PPP specific OUI from IANA.  This OUI   shall be assigned from the 'CF0000' series.  This has both the   "locally-assigned" and "broadcast/multicast" bits set to 1; that is,   the least significant two bits of the most significant octet are both   set to 1.   Appearance in memory, bits transmitted right-to-left within octets,Simpson                      Informational                      [Page 4]

RFC 2153                 PPP vendor extensions                  May 1997   octets transmitted left-to-right:   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   |1 1 0 0 1 1 1 1|x x x x x x x x|x x x x x x x x|   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                | |                | Multicast                Local   Rationale:      This is defined for vendors that are not able to use IEEE      assignments, such as software-only vendors.      It is not clear how the IEEE assigns blocks.  In some instances,      the "locally-assigned" bit is known to have been used.      However, multicast has no meaning in PPP.  Therefore, an IEEE      assigned OUI would have the multicast bit cleared to 0.      The 'CF0000' series was arbitrarily chosen to match the PPP NLPID      'CF', as a matter of mnemonic convenience.Security Considerations   Security issues are not discussed in this document.References   [1]   Simpson, W., Editor, "The Point-to-Point Protocol (PPP)", STD         51,RFC 1661, DayDreamer, July 1994.   [2]   Reynolds, J.K., Postel, J.B., "Assigned Numbers",RFC-1700,         July 1992.Simpson                      Informational                      [Page 5]

RFC 2153                 PPP vendor extensions                  May 1997Contacts   Comments about this document should be discussed on the ietf-   ppp@merit.edu mailing list.   This document was reviewed by the Point-to-Point Protocol Working   Group of the Internet Engineering Task Force (IETF).  The working   group can be contacted via the current chair:      Karl Fox      Ascend Communications      655 Metro Place South, Suite 379      Dublin, Ohio  43017          karl@Ascend.com   Questions about this document can also be directed to:      William Allen Simpson      DayDreamer      Computer Systems Consulting Services      1384 Fontaine      Madison Heights, Michigan  48071          wsimpson@UMich.edu          wsimpson@GreenDragon.com (preferred)Simpson                      Informational                      [Page 6]