how to help with lat long encoding in the dns

RFC 1876, `A Means for Expressing Location Information in the Domain Name System' defines the format of a DNS Resource Record (RR) for associating host location mappings to host names within a domain.

RDATA format

       MSB                                           LSB
       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
      0|        VERSION        |         SIZE          |
       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
      2|       HORIZ PRE       |       VERT PRE        |
       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
      4|                   LATITUDE                    |
       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
      6|                   LATITUDE                    |
       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
      8|                   LONGITUDE                   |
       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
     10|                   LONGITUDE                   |
       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
     12|                   ALTITUDE                    |
       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
     14|                   ALTITUDE                    |
       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
   (octet)

Master file format

The LOC record is expressed in a master file in the following format:

< owner> < TTL> class> LOC ( d1 [m1 [s1]] {"N"|"S"} d2 [m2 [s2]] {"E"|"W"} alt["m"] [siz["m"] [hp["m"] [vp["m"]]]] )

(Parentheses used for multi-line data as specified in [RFC 1035] section 5.1.)

where:

d1: [0 .. 90] (degrees latitude)

d2: [0 .. 180] (degrees longitude)

m1, m2: [0 .. 59] (minutes latitude/longitude)

s1, s2: [0 .. 59.999] (seconds latitude/longitude)

alt: [-100000.00 .. 42849672.95] BY .01 (altitude in meters)

siz, hp, vp: [0 .. 90000000.00] (size/precision in meters)

If omitted, minutes and seconds default to zero, size defaults to 1m, horizontal precision defaults to 10000m, and vertical precision defaults to 10m. These defaults are chosen to represent typical ZIP/postal code area sizes, since it is often easy to find approximate geographical location by ZIP/postal code.

Example data

;;;
;;; note that these data would not all appear in one zone file
;;;

;; network LOC RR derived from ZIP data.  note use of precision defaults
cambridge-net.kei.com.        LOC   42 21 54 N 71 06 18 W -24m 30m

;; higher-precision host LOC RR.  note use of vertical precision default
loiosh.kei.com.               LOC   42 21 43.952 N 71 5 6.344 W
                                    -24m 1m 200m

pipex.net.                    LOC   52 14 05 N 00 08 50 E 10m

curtin.edu.au.                LOC   32 7 19 S 116 2 25 E 10m

rwy04L.logan-airport.boston.  LOC   42 21 28.764 N 71 00 51.617 W
                                    -44m 2000m

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20 mar 96, comments to kc@caida.net