Binary to Decimal Conversion for LCI

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Binary to Decimal Conversion for LCI

• IETF 67 GeoPriv WG
• 11/06/2006
• San Diego

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What is it?

• draft-schnizlein-geopriv-binary-lci-00
• This document describes the nature of the data
  expressed in the geographic LCI defined in RFC
  3825, and includes examples of conversion from
  its binary format to decimal character strings.

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LCI

• The LCI encodes a point's latitude, longitude
  and altitude, along with the resolution of that
  point. LCI does not encode boundaries of an
  arbitrary region. The resolution is nothing more
  than the representation of significant digits for
  the fixed-length, binary values in the LCI.

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Programming Hints/Examples

• C code examples need to be tested.
• Example of binary math to determine the LCI value
  and resolution given a range.

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List Comments

• Expressing resolution of the significant bits in
  a fixed-length binary value is not the same as
  geo-coordinate measurement errors
• (ex. 38.9 does not equal 38.9000000)
• RFC3825 uses FIXED-LENGTH fields, which implies
  the need to express resolution other than as a
  variable number of significant digits.

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List Comments

• No example of the xml (pidf-lo) wrapping the
  decimal-string value is necessary.
• Appendix A of pidf-lo profile incorrectly
  characterizes LCI
• This draft does not change RFC3825