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Internet Engineering Task Force (IETF)                         M. EislerRequest for Comments: 5665                                        NetAppUpdates:1833                                               January 2010Category: Standards TrackISSN: 2070-1721IANA Considerations for Remote Procedure Call (RPC)Network Identifiers and Universal Address FormatsAbstract   This document lists IANA Considerations for Remote Procedure Call   (RPC) Network Identifiers (netids) and RPC Universal Network   Addresses (uaddrs).  This document updates, but does not replace,RFC1833.Status of This Memo   This is an Internet Standards Track document.   This document is a product of the Internet Engineering Task Force   (IETF).  It represents the consensus of the IETF community.  It has   received public review and has been approved for publication by the   Internet Engineering Steering Group (IESG).  Further information on   Internet Standards is available inSection 2 of RFC 5741.   Information about the current status of this document, any errata,   and how to provide feedback on it may be obtained athttp://www.rfc-editor.org/info/rfc5665.Copyright Notice   Copyright (c) 2010 IETF Trust and the persons identified as the   document authors.  All rights reserved.   This document is subject toBCP 78 and the IETF Trust's Legal   Provisions Relating to IETF Documents   (http://trustee.ietf.org/license-info) in effect on the date of   publication of this document.  Please review these documents   carefully, as they describe your rights and restrictions with respect   to this document.  Code Components extracted from this document must   include Simplified BSD License text as described in Section 4.e of   the Trust Legal Provisions and are provided without warranty as   described in the Simplified BSD License.Eisler                       Standards Track                    [Page 1]

RFC 5665                       RPC Netids                   January 2010Table of Contents1. Introduction and Motivation .....................................32. Requirements Language ...........................................3   3. Considerations for the Netid of the Stream Control      Transmission Protocol ...........................................34. Security Considerations .........................................35. IANA Considerations .............................................35.1. IANA Considerations for Netids .............................45.1.1. Initial Registry ....................................65.1.2. Updating Registrations ..............................85.2. IANA Considerations for Uaddr Formats ......................85.2.1. Initial Registry ....................................95.2.2. Updating Registrations .............................105.2.3. Uaddr Formats ......................................10                  5.2.3.1. Uaddr Format for System V Release4 Loopback Transports .....................105.2.3.2. Uaddr Format for Netid "-" ................105.2.3.3. Uaddr Format for Most IPv4 Transports .....115.2.3.4. Uaddr Format for Most IPv6 Transports .....115.2.3.5. Uaddr Format for ICMP over IPv4 and IPv6 ..115.3. Cross Referencing between the Netid and Format Registry ...125.4. Port Assignment for NFS over SCTP .........................126. References .....................................................126.1. Normative References ......................................126.2. Informative References ....................................12Appendix A.  Acknowledgments ......................................14Eisler                       Standards Track                    [Page 2]

RFC 5665                       RPC Netids                   January 20101.  Introduction and Motivation   The concepts of an RPC (defined inRFC 5531 [4]) Network Identifier   (netid) and an RPC Universal Address (uaddr) were introduced inRFC1833 [1] for distinguishing network addresses of multiple protocols   and representing those addresses in a canonical form.RFC 1833   states that a netid "is defined by a system administrator based on   local conventions, and cannot be depended on to have the same value   on every system".  (The netid is contained in the field r_netid of   the data type rpcb_entry, and the uaddr is contained in the field   r_addr of the same data type, where rpcb_entry is defined inRFC1833.)  Since the publication ofRFC 1833, it has been found that   protocols like Network File System version 4 (NFSv4.0) [5] and RPC/   RDMA (Remote Direct Memory Access) [6] depend on consistent values of   netids and representations of uaddrs.  Current practices tend to   ensure this consistency.  Thus, this document identifies the   considerations for IANA to establish registries of netids and uaddr   formats for RPC and specifies the initial content of the two   registries.2.  Requirements Language   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this   document are to be interpreted as described inRFC 2119 [2].3.  Considerations for the Netid of the Stream Control Transmission    Protocol   The Stream Control Transmission Protocol (SCTP) (described inRFC4960 [7]) is a connection-oriented protocol that supports both byte-   streamed and record-oriented data transfer.  When the "sctp" and   "sctp6" netids are used, the Open Network Computing (ONC) RPC Record   Marking standard (seeSection 11 of RFC 5531 [4]) is not used;   instead, SCTP's native record-oriented data transfer is used.4.  Security Considerations   Since this document is only concerned with the IANA management of the   Network Identifier (netid) and Universal Network Addresses (uaddrs)   format registry, it raises no new security issues.5.  IANA Considerations   This section uses terms that are defined inRFC 5226 [8].Eisler                       Standards Track                    [Page 3]

RFC 5665                       RPC Netids                   January 20105.1.  IANA Considerations for Netids   IANA has created a registry called "ONC RPC Netids".  The remainder   of this section describes the registry.   All assignments to the ONC RPC Netids registry are made on one of two   bases:   o  A First Come First Served basis subregistry per Section 4.1 ofRFC5226.   o  A Standards Action basis subregistry perSection 4.1 of RFC 5226.   The eXternal Data Representation (XDR) encoding allows netids to be   up to 2^32 - 1 octets in length, but the registry will only allow a   much shorter length.  Assignments made on a Standards Action basis   should be assigned netids 1 to 8 octets long.  Assignments made on a   First Come First Served basis should be assigned netids 9 to 128   octets long.  Some exceptions are listed in Table 2.   Some portion of the netid name space is Reserved:   o  All netids, regardless of length, that start with the prefixes      "STDS" or "FCFS" are Reserved, in order to extend the name space      of either Standards Action or First Come First Served bases.   o  To give the IESG the flexibility in the future to permit Private      and Experimental Uses, all netids with the prefixes "PRIV" or      "EXPE" are Reserved.   o  To prevent confusion with the control protocol by the same name      [9], netids with the prefix "ICMP" are Reserved.   o  Since netids are not constructed in an explicit hierarchical      manner, this document does not provide for Hierarchical Allocation      of netids.  Nonetheless, all netids containing the octet "." are      Reserved for future possible provision of Hierarchical Allocation.   o  The zero length netid is Reserved.   A recommended convention for netids corresponding to transports that   work over the IPv6 protocol is to have "6" as the last character in   the netid's name.   There are two subregistries of netids: one for Standards Action   assignments and one for First Come First Served assignments.  Each   registry of netids is a list of assignments, each containing five   fields for each assignment.Eisler                       Standards Track                    [Page 4]

RFC 5665                       RPC Netids                   January 2010   1.  A US-ASCII string name that is the actual netid.  The netid       should be 1 to 8 octets long for the Standards Action       subregistry, and 9 to 128 octets long for the First Come First       Served subregistry.  The netid MUST NOT conflict with any other       registered netid.  Despite the fact that netids are case       sensitive, the netid, when mapped to all upper case, MUST NOT       conflict with the value of any other registered netid after the       registered netid is mapped to upper case.  In addition, when       mapped to upper case, the prefix of the netid MUST NOT be equal       to a Reserved prefix.   2.  A constant name that can be used for software programs that wish       to use the transport protocol associated with the netid.  The       name of the constant typically has the prefix "NC_", and a suffix       equal to the upper-case version of the netid.  This constant name       should be a constant that is valid in the 'C' programming       language.  This constant name MUST NOT conflict with any other       netid constant name.  Constant names with the prefix "NC_STDS",       "NC_FCFS", "NC_PRIV", "NC_EXPE", and "NC_ICMP" are Reserved.       Constant names with a prefix of "NC_" and a total length of 11       characters or less should be for assignments made on the       Standards Action basis.  The constant "NC_" is Reserved.  The       constant name can be 1 to 131 octets long.       Given the typical derivation of the constant name from the netid,       the registration of the constant might be considered redundant.       This is not always true.  For example, a netid might use a       character that is not valid in the programming language.  The       first entry of Table 1 provides such an example.   3.  A description and/or a reference to a description of how the       netid will be used.  For assignments made on a First Come First       Served basis, the description should include, if applicable, a       reference to the transport and network protocols corresponding to       the netid.  For assignments made on a Standards Action basis, the       description field must include the RFC numbers of the protocol       associated with the netid, including, if applicable, RFC numbers       of the transport and network protocols.   4.  A point of contact of the registrant.  For assignments made on a       First Come First Served basis:       *  the point of contact should include an email address.       *  subject to authorization by a Designated Expert, the point of          contact may be omitted for extraordinary situations, such as          the registration of a commonly used netid where the owner is          unknown.Eisler                       Standards Track                    [Page 5]

RFC 5665                       RPC Netids                   January 2010       For assignments made on a Standards Action basis, the point of       contact is always determined by IESG.   5.  A numerical value, used to cross reference the netid assignment       with an assignment in the uaddr format registry (seeSection 5.2).  If the registrant is registering a netid that       cross references an existing assignment in the uaddr format       registry, then the registrant provides the actual value of the       cross reference along with the date the registrant retrieved the       cross reference value from the uaddr format registry.  If the       registrant is registering both a new netid and new uaddr format,       then the registrant provides a value of TBD1 in the netid       request, and uses TBD1 in the uaddr format request.  IANA will       then substitute TBD1 for the cross reference number IANA       allocates.  Note that if a document requests multiple netid and       uaddr assignments, each additional uaddr format cross reference       will be identified as TBD2, TBD3, ..., etc.5.1.1.  Initial Registry   The initial list of netids is broken into two subregistries: those   assigned on a First Come First Served basis in Table 1 and those   assigned on a Standards Action basis in Table 2.  These lists will   change as IANA registers additional netids as needed, and the   authoritative list of registered netids will always live with IANA.Eisler                       Standards Track                    [Page 6]

RFC 5665                       RPC Netids                   January 2010   +-------------+--------------+---------------------------+-----+----+   | Netid       | Constant     | Description and/or        | PoC | CR |   |             | Name         | Reference                 |     |    |   +-------------+--------------+---------------------------+-----+----+   | "-"         | NC_NOPROTO   |RFC1833 [1],              |     | 1  |   |             |              |Section 5.2.3.2 of RFC    |     |    |   |             |              | 5665                      |     |    |   | "ticlts"    | NC_TICLTS    | The loop back             |     | 0  |   |             |              | connectionless transport  |     |    |   |             |              | used in System V Release  |     |    |   |             |              | 4 and other operating     |     |    |   |             |              | systems.  Although this   |     |    |   |             |              | assignment is made on a   |     |    |   |             |              | First Come First Served   |     |    |   |             |              | basis and is fewer than   |     |    |   |             |              | nine characters long, the |     |    |   |             |              | exception is authorized.  |     |    |   |             |              | See [10].                 |     |    |   | "ticots"    | NC_TICOTS    | The loop back             |     | 0  |   |             |              | connection-oriented       |     |    |   |             |              | transport used in System  |     |    |   |             |              | V Release 4 and other     |     |    |   |             |              | operating systems.  See   |     |    |   |             |              | [10].  Although this      |     |    |   |             |              | assignment is made on a   |     |    |   |             |              | First Come First Served   |     |    |   |             |              | basis and is fewer than   |     |    |   |             |              | nine characters long, the |     |    |   |             |              | exception is authorized.  |     |    |   | "ticotsord" | NC_TICOTSORD | The loop back             |     | 0  |   |             |              | connection-oriented with  |     |    |   |             |              | orderly-release transport |     |    |   |             |              | used in System V Release  |     |    |   |             |              | 4 and other operating     |     |    |   |             |              | systems.  See [10].       |     |    |   +-------------+--------------+---------------------------+-----+----+        Table 1: Initial First Come First Served Netid Assignments   PoC: Point of Contact.   CR: Cross Reference to the Uaddr Format Registry.Eisler                       Standards Track                    [Page 7]

RFC 5665                       RPC Netids                   January 2010   +---------+----------+----------------------------------+------+----+   | Netid   | Constant | RFC(s) and Description (if       | PoC  | CR |   |         | Name     | needed)                          |      |    |   +---------+----------+----------------------------------+------+----+   | "rdma"  | NC_RDMA  |RFC 5666 [6],RFC 791 [11]       | IESG | 2  |   | "rdma6" | NC_RDMA6 |RFC 5666 [6],RFC 2460 [12]      | IESG | 3  |   | "sctp"  | NC_SCTP  |RFC 4960 [7],RFC 791 [11],      | IESG | 2  |   |         |          |Section 3 of RFC 5665            |      |    |   | "sctp6" | NC_SCTP6 |RFC 4960 [7],RFC 2460 [12],     | IESG | 3  |   |         |          |Section 3 of RFC 5665            |      |    |   | "tcp"   | NC_TCP   |RFC 793 [13],RFC 791 [11],      | IESG | 2  |   |         |          |Section 11 of RFC 5531 [4]       |      |    |   | "tcp6"  | NC_TCP6  |RFC 793 [13],RFC 2460 [12],     | IESG | 3  |   |         |          |Section 11 of RFC 5531 [4]       |      |    |   | "udp"   | NC_UDP   |RFC 768 [14],RFC 791 [11]       | IESG | 2  |   | "udp6"  | NC_UDP6  |RFC 768 [14],RFC 2460 [12]      | IESG | 3  |   +---------+----------+----------------------------------+------+----+            Table 2: Initial Standards Action Netid Assignments5.1.2.  Updating Registrations   PerSection 5.2 of RFC 5226, the registrant is always permitted to   update a registration made on a First Come First Served basis   "subject to the same constraints and review as with new   registrations".  The IESG or a Designated Expert is permitted to   update any registration made on a First Come First Served basis,   which normally is done when the PoC cannot be reached in order to   make necessary updates.  Examples where an update would be needed   include, but are not limited to: the email address or other contact   information becomes invalid; the reference to the corresponding   protocol becomes obsolete or unavailable;RFC 1833 is updated or   replaced in such a way that the scope of netids changes, requiring   additional fields in the assignment.   Only the IESG, on the advice of a Designated Expert, can update a   registration made on a Standards Action basis.5.2.  IANA Considerations for Uaddr Formats   IANA has created a registry called "ONC RPC Uaddr Format Registry"   (called the "format registry" for the remainder of this document).   The remainder of this section describes the registry.Eisler                       Standards Track                    [Page 8]

RFC 5665                       RPC Netids                   January 2010   All assignments to the format registry are made on one of two bases:   o  First Come First Served basis perSection 4.1 of RFC 5226.   o  Standards Action perSection 4.1 of RFC 5226.   The registry of formats is a list of assignments, each containing   four fields for each assignment.   1.  The basis for the assignment, which can be either FCFS for First       Come First Served assignments or STDS for Standards Action       assignments.   2.  A description and/or reference to a description of the actual       uaddr format.  Assignments made on a Standards Action basis       always have a reference to an RFC.   3.  For assignments made on a First Come First Served basis, a point       of contact, including an email address.  Subject to authorization       by a Designated Expert, the point of contact may be omitted for       extraordinary situations, such as the registration of a commonly       used format where the owner is unknown.  For assignments made on       a Standards Action basis, the point of contact is always       determined by the IESG.   4.  A numerical value, used to cross reference the format assignment       with an assignment in the netid registry.  The registrant       provides a value of TBD1 for the cross reference field when       requesting an assignment.  IANA will assign TBD1 to a real value.       Note that if a document requests multiple uaddr assignments, each       additional uaddr format cross reference will be identified as       TBD2, TBD3, ..., etc.   All requests for assignments to the format registry on a Standards   Action basis are only for Standards Track RFCs approved by the IESG.5.2.1.  Initial Registry   The initial list of formats is in Table 3.  This list will change as   IANA registers additional formats as needed, and the authoritative   list of registered formats will always live with IANA.Eisler                       Standards Track                    [Page 9]

RFC 5665                       RPC Netids                   January 2010   +-------+-----------------------------------------------+------+----+   | Basis | Description and/or Reference                  | PoC  | CR |   +-------+-----------------------------------------------+------+----+   | FCFS  | System V Release 4 loopback transport uaddr   |      | 0  |   |       | format.Section 5.2.3.1 of RFC 5665          |      |    |   | FCFS  | Uaddr format for NC_NOPROTO.Section 5.2.3.2 |      | 1  |   |       | ofRFC 5665                                   |      |    |   | STDS  | Uaddr format for IPv4 transports.             | IESG | 2  |   |       |Section 5.2.3.3 of RFC 5665                   |      |    |   | STDS  | Uaddr format for IPv6 transports.             | IESG | 3  |   |       |Section 5.2.3.4 of RFC 5665                   |      |    |   +-------+-----------------------------------------------+------+----+                    Table 3: Initial Format Assignments5.2.2.  Updating Registrations   The registrant is always permitted to update a registration made on a   First Come First Served basis "subject to the same constraints and   review as with new registrations."  The IESG is permitted to update   any registration made on a First Come First Served basis, which   normally is done when the PoC cannot be reached in order to make   necessary updates.  Examples where an update would be needed include,   but are not limited to: the email address or other contact   information becomes invalid; the reference to the format description   becomes obsolete or unavailable;RFC 1833 is updated or replaced in   such a way that the scope of uaddr formats changes, requiring   additional fields in the assignment.   Only the IESG, on the advice of a Designated Expert, can update a   registration made on a Standards Action basis.5.2.3.  Uaddr Formats5.2.3.1.  Uaddr Format for System V Release 4 Loopback Transports   AlthoughRFC 1833 specifies the uaddr as the XDR data type string   (hence, limited to US-ASCII), implementations of the System V Release   4 loopback transports will use an opaque string of octets.  Thus, the   format of a loopback transport address is any non-zero length array   of octets.5.2.3.2.  Uaddr Format for Netid "-"   There is no address format for netid "-".  This netid is apparently   for internal use for supporting some implementations ofRFC 1833.Eisler                       Standards Track                   [Page 10]

RFC 5665                       RPC Netids                   January 20105.2.3.3.  Uaddr Format for Most IPv4 Transports   Most transport protocols that operate over IPv4 use 16-bit port   numbers, including RDMA [6], SCTP [7], TCP [13], and UDP [14].  The   format of the uaddr for the above 16-bit port transports (when used   over IPv4) is the US-ASCII string:      h1.h2.h3.h4.p1.p2   The prefix "h1.h2.h3.h4" is the standard textual form for   representing an IPv4 address, which is always four octets long.   Assuming big-endian ordering, h1, h2, h3, and h4 are, respectively,   the first through fourth octets each converted to ASCII-decimal.  The   suffix "p1.p2" is a textual form for representing a service port.   Assuming big-endian ordering, p1 and p2 are, respectively, the first   and second octets each converted to ASCII-decimal.  For example, if a   host, in big-endian order, has an address in hexadecimal of   0xC0000207 and there is a service listening on, in big-endian order,   port 0xCB51 (decimal 52049), then the complete uaddr is   "192.0.2.7.203.81".5.2.3.4.  Uaddr Format for Most IPv6 Transports   Most transport protocols that operate over IPv6 use 16-bit port   numbers, including RDMA [6], SCTP [7], TCP [13], and UDP [14].  The   format of the uaddr for the above 16-bit port transports (when used   over IPv6) is the US-ASCII string:      x1:x2:x3:x4:x5:x6:x7:x8.p1.p2   The suffix "p1.p2" is the service port, and is computed the same way   as with uaddrs for transports over IPv4 (seeSection 5.2.3.3).  The   prefix "x1:x2:x3:x4:x5:x6:x7:x8" is the preferred textual form for   representing an IPv6 address as defined inSection 2.2 of RFC 4291   [3].  Additionally, the two alternative forms specified inSection2.2 of RFC 4291 are also acceptable.5.2.3.5.  Uaddr Format for ICMP over IPv4 and IPv6   As ICMP is not a true transport, there is no uaddr format for ICMP.   The netid assignments "icmp" and "icmp6" and their shared uaddr   "format" are listed to prevent any registrant from allocating the   netids "icmp" and "icmp6" for a purpose that would likely cause   confusion.Eisler                       Standards Track                   [Page 11]

RFC 5665                       RPC Netids                   January 20105.3.  Cross Referencing between the Netid and Format Registry   The last field of the netids registry is used to cross reference with   the last field of the format registry.  IANA is under no obligation   to maintain the same numeric values in cross references when updating   each registry; i.e., IANA is free to "re-number" these corresponding   fields.  However, if IANA does so, both the netid and format   registries must be updated atomically.5.4.  Port Assignment for NFS over SCTP   Port 2049 is assigned to NFS over SCTP for the sctp and sctp6 netids.6.  References6.1.  Normative References   [1]   Srinivasan, R., "Binding Protocols for ONC RPC Version 2",RFC 1833, August 1995.   [2]   Bradner, S., "Key words for use in RFCs to Indicate Requirement         Levels",BCP 14,RFC 2119, March 1997.   [3]   Hinden, R. and S. Deering, "IP Version 6 Addressing         Architecture",RFC 4291, February 2006.6.2.  Informative References   [4]   Thurlow, R., "RPC: Remote Procedure Call Protocol Specification         Version 2",RFC 5531, May 2009.   [5]   Shepler, S., Callaghan, B., Robinson, D., Thurlow, R., Beame,         C., Eisler, M., and D. Noveck, "Network File System (NFS)         version 4 Protocol",RFC 3530, April 2003.   [6]   Talpey, T. and B. Callaghan, "Remote Direct Memory Access         Transport for Remote Procedure Call",RFC 5666, January 2010.   [7]   Stewart, R., Ed., "Stream Control Transmission Protocol",RFC 4960, September 2007.   [8]   Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA         Considerations Section in RFCs",BCP 26,RFC 5226, May 2008.   [9]   Postel, J., "Internet Control Message Protocol", STD 5,RFC 792, September 1981.Eisler                       Standards Track                   [Page 12]

RFC 5665                       RPC Netids                   January 2010   [10]  American Telephone and Telegraph Company, "UNIX System V,         Release 4 Programmer's Guide: Networking Interfaces, ISBN         0139470786", 1990.   [11]  Postel, J., "Internet Protocol", STD 5,RFC 791,         September 1981.   [12]  Deering, S. and R. Hinden, "Internet Protocol, Version 6 (IPv6)         Specification",RFC 2460, December 1998.   [13]  Postel, J., "Transmission Control Protocol", STD 7,RFC 793,         September 1981.   [14]  Postel, J., "User Datagram Protocol", STD 6,RFC 768,         August 1980.Eisler                       Standards Track                   [Page 13]

RFC 5665                       RPC Netids                   January 2010Appendix A.  Acknowledgments   Lisa Dusseault, Lars Eggert, Pasi Eronen, Tim Polk, Juergen   Schoenwaelder, and Robert Sparks reviewed the document and gave   valuable feedback.Author's Address   Mike Eisler   NetApp   5765 Chase Point Circle   Colorado Springs, CO  80919   US   Phone: +1-719-599-9026   EMail: mike@eisler.comEisler                       Standards Track                   [Page 14]