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author | Thomas Voss <mail@thomasvoss.com> | 2024-11-27 20:54:24 +0100 |
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committer | Thomas Voss <mail@thomasvoss.com> | 2024-11-27 20:54:24 +0100 |
commit | 4bfd864f10b68b71482b35c818559068ef8d5797 (patch) | |
tree | e3989f47a7994642eb325063d46e8f08ffa681dc /doc/rfc/rfc1712.txt | |
parent | ea76e11061bda059ae9f9ad130a9895cc85607db (diff) |
doc: Add RFC documents
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diff --git a/doc/rfc/rfc1712.txt b/doc/rfc/rfc1712.txt new file mode 100644 index 0000000..40d8857 --- /dev/null +++ b/doc/rfc/rfc1712.txt @@ -0,0 +1,395 @@ + + + + + + +Network Working Group C. Farrell +Request for Comments: 1712 M. Schulze +Category: Experimental S. Pleitner + D. Baldoni + Curtin University of Technology + November 1994 + + + DNS Encoding of Geographical Location + +Status of this Memo + + This memo defines an Experimental Protocol for the Internet + community. This memo does not specify an Internet standard of any + kind. Discussion and suggestions for improvement are requested. + Distribution of this memo is unlimited. + +Abstract + + This document defines the format of a new Resource Record (RR) for + the Domain Naming System (DNS), and reserves a corresponding DNS type + mnemonic and numerical code. This definition deals with associating + geographical host location mappings to host names within a domain. + The data shown in this document is fictitious and does not + necessarily reflect the real Internet. + +1. Introduction + + It has been a long standing problem to relate IP numbers to + geographical locations. The availability of Geographical location + information has immediate applications in network management. Such + information can be used to supplement the data already provided by + utilities such as whois [Har85], traceroute [VJ89], and nslookup + [UCB89]. The usefulness and functionality of these already widely + used tools would be greatly enhanced by the provision of reliable + geographical location information. + + The ideal way to manage and maintain a database of information, such + as geographical location of internet hosts, is to delegate + responsibility to local domain administrators. A large distributed + database could be implemented with a simple mechanism for updating + the local information. A query mechanism also has to be available + for checking local entries, as well as inquiring about data from + non-local domains. + + + + + + + +Farrell, Schulze, Pleitner & Baldoni [Page 1] + +RFC 1712 DNS Encoding of Geographical Location November 1994 + + +2. Background + + The Internet continues to grow at an ever increasing rate with IP + numbers allocated on a first-come-first-serve basis. Deciding when + and how to setup a database of geographical information about + internet hosts presented a number of options. The uumap project + [UU85] was the first serious attempt to collect geographical location + data from sites and store it centrally. This project met with + limited success because of the difficulty in maintaining and updating + a large central database. Another problem was the lack of tools for + the checking the data supplied, this problem resulted in some + erroneous data entering the database. + +2.1 SNMP: + + Using an SNMP get request on the sysLocation MIB (Management + Information Base) variable was also an option, however this would + require the host to be running an appropriate agent with public read + access. It was also felt that MIB data should reflect local + management data (e.g., "this" host is on level 5 room 74) rather than + a hosts geographical position. This view is supported in the + examples given in literature in this area [ROSE91]. + +2.2 X500: + + The X.500 Directory service [X.500.88] defined as part of the ISO + standards also appears as a potential provider of geographical + location data. However due to the limited implementations of this + service it was decided to defer this until this service gains wider + use and acceptance within the Internet community. + +2.3 BIND: + + The DNS [Mock87a][Mock87b] represents an existing system ideally + suited to the provision of host specific information. The DNS is a + widely used and well-understood mechanism for providing a distributed + database of such information and its extensible nature allows it to + be used to disseminate virtually any information. The most commonly + used DNS implementation is the Berkeley Internet Name Domain server + BIND [UCB89]. The information we wished to make available needed to + be updated locally but available globally; a perfect match with the + services provided by the DNS. Current DNS servers provide a variety + of useful information about hosts in their domain but lack the + ability to report a host's geographical location. + + + + + + + +Farrell, Schulze, Pleitner & Baldoni [Page 2] + +RFC 1712 DNS Encoding of Geographical Location November 1994 + + +3. RDATA Format + + MSB LSB + +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ + / LONGITUDE / + +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ + / LATITUDE / + +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ + / ALTITUDE / + +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ + + where: + + LONGITUDE The real number describing the longitude encoded as a + printable string. The precision is limited by 256 charcters + within the range -90..90 degrees. Positive numbers + indicate locations north of the equator. + + LATITUDE The real number describing the latitude encoded as a + printable string. The precision is limited by 256 charcters + within the range -180..180 degrees. Positive numbers + indicate locations east of the prime meridian. + + ALTITUDE The real number describing the altitude (in meters) from + mean sea-level encoded as a printable string. The precision + is limited by 256 charcters. Positive numbers indicate + locations above mean sea-level. + + Latitude/Longitude/Altitude values are encoded as strings as to avoid + the precision limitations imposed by encoding as unsigned integers. + Although this might not be considered optimal, it allows for a very + high degree of precision with an acceptable average encoded record + length. + +4. The GPOS RR + + The geographical location is defined with the mnemonic GPOS and type + code 27. + + GPOS has the following format: + <owner> <ttl> <class> GPOS <longitude> <latitude> <altitude> + + A floating point format was chosen to specify geographical locations + for reasons of simplicity. This also guarantees a concise + unambiguous description of a location by enforcing three compulsory + numerical values to be specified. + + + + + +Farrell, Schulze, Pleitner & Baldoni [Page 3] + +RFC 1712 DNS Encoding of Geographical Location November 1994 + + + The owner, ttl, and class fields are optional and default to the last + defined value if omitted. The longitude is a floating point number + ranging from -90 to 90 with positive values indicating locations + north of the equator. For example Perth, Western Australia is + located at 32^ 7` 19" south of the equator which would be specified + as -32.68820. The latitude is a number ranging from -180.0 to 180.0. + For example Perth, Western Australia is located at 116^ 2' 25" east + of the prime meridian which would be specified as 116.86520. Curtin + University, Perth is also 10 meters above sea-level. + + The valid GPOS record for a host at Curtin University in Perth + Western Australia would therefore be: + + GPOS -32.6882 116.8652 10.0 + + There is no limit imposed on the number of decimal places, although + the length of the encoded string is limited to 256 characters for + each field. It is also suggested that administrators limit their + entries to the minimum number of necessary characters in each field. + +5. Master File Format + + Each host requires its own GPOS field in the corresponding DNS RR to + explicitly specify its geographical location and altitude. If the + GPOS field is omitted, a DNS enquiry will return no position + information for that host. + + Consider the following example: + +; Authoritative data for cs.curtin.edu.au. +; +@ IN SOA marsh.cs.curtin.edu.au. postmaster.cs.curtin.edu.au. + ( + 94070503 ; Serial (yymmddnn) + 10800 ; Refresh (3 hours) + 3600 ; Retry (1 hour) + 3600000 ; Expire (1000 hours) + 86400 ; Minimum (24 hours) + ) + + IN NS marsh.cs.curtin.edu.au. + +marsh IN A 134.7.1.1 + IN MX 0 marsh + IN HINFO SGI-Indigo IRIX-4.0.5F + IN GPOS -32.6882 116.8652 10.0 +ftp IN CNAME marsh + + + + +Farrell, Schulze, Pleitner & Baldoni [Page 4] + +RFC 1712 DNS Encoding of Geographical Location November 1994 + + +lillee IN A 134.7.1.2 + IN MX 0 marsh + IN HINFO SGI-Indigo IRIX-4.0.5F + IN GPOS -32.6882 116.8652 10.0 + +hinault IN A 134.7.1.23 + IN MX 0 marsh + IN HINFO SUN-IPC SunOS-4.1.3 + IN GPOS -22.6882 116.8652 250.0 + +merckx IN A 134.7.1.24 + IN MX 0 marsh + IN HINFO SUN-IPC SunOS-4.1.1 + +ambrose IN A 134.7.1.99 + IN MX 0 marsh + IN HINFO SGI-CHALLENGE_L IRIX-5.2 + IN GPOS -32.6882 116.8652 10.0 + + The hosts marsh, lillee, and ambrose are all at the same geographical + location, Perth Western Australia (-32.68820 116.86520). The host + hinault is at a different geographical location, 10 degrees north of + Perth in the mountains (-22.6882 116.8652 250.0). For security + reasons we do not wish to give the location of the host merckx. + + Although the GPOS clause is not a standard entry within BIND + configuration files, most vendor implementations seem to ignore + whatever is not understood upon startup of the DNS. Usually this + will result in a number of warnings appearing in system log files, + but in no way alters naming information or impedes the DNS from + performing its normal duties. + + + + + + + + + + + + + + + + + + + + +Farrell, Schulze, Pleitner & Baldoni [Page 5] + +RFC 1712 DNS Encoding of Geographical Location November 1994 + + +7. References + + [ROSE91] Rose M., "The Simple Book: An Introduction to + Management of TCP/IP-based Internets", Prentice-Hall, + Englewood Cliffs, New Jersey, 1991. + + [X.500.88] CCITT: The Directory - Overview of Concepts, Models + and Services", Recommendations X.500 - X.521. + + [Har82] Harrenstein K, Stahl M., and E. Feinler, + "NICNAME/WHOIS" RFC 812, SRI NIC, March 1982. + + [Mock87a] Mockapetris P., "Domain Names - Concepts and + Facilities", STD 13, RFC 1034, USC/Information + Sciences Institute, November 1987. + + [Mock87b] Mockapetris P., "Domain Names - Implementation and + Specification", STD 13, RFC 1035, USC/Information + Sciences Institute, November 1987. + + [FRB93] Ford P., Rekhter Y., and H-W. Braun, "Improving the + Routing and Addressing of IP", IEEE Network + Vol.7, No. 3, pp. 11-15, May 1993. + + [VJ89] Jacobsen V., "The Traceroute(8) Manual Page", + Lawrence Berkeley Laboratory, Berkeley, + CA, February 1989. + + [UCB89] University of California, "BIND: Berkeley Internet + Name Domain Server", 1989. + [UU85] UUCP Mapping Project, Software available via + anonymous FTP from ftp.uu.net., 1985. + +8. Security Considerations + + Once information has been entered into the DNS, it is considered + public. + + + + + + + + + + + + + + +Farrell, Schulze, Pleitner & Baldoni [Page 6] + +RFC 1712 DNS Encoding of Geographical Location November 1994 + + +9. Authors' Addresses + + Craig Farrell + Department of Computer Science + Curtin University of technology + GPO Box U1987 Perth, + Western Australia + + EMail: craig@cs.curtin.edu.au + + + Mike Schulze + Department of Computer Science + Curtin University of technology + GPO Box U1987 Perth, + Western Australia + + EMail: mike@cs.curtin.edu.au + + + Scott Pleitner + Department of Computer Science + Curtin University of technology + GPO Box U1987 Perth, + Western Australia + + EMail: pleitner@cs.curtin.edu.au + + + Daniel Baldoni + Department of Computer Science + Curtin University of technology + GPO Box U1987 Perth, + Western Australia + + EMail: flint@cs.curtin.edu.au + + + + + + + + + + + + + + + +Farrell, Schulze, Pleitner & Baldoni [Page 7] + |