BOOTP / DHCP option 123, GeoConf
Description Glossary RFCs Publications Obsolete RFCs

Description:

Protocol suite: TCP/IP.
Protocol type:Application layer configuration protocol.
Option length:bytes.
Links: IANA: BOOTP and DHCP options.
MAC header IP header UDP header BOOTP | DHCP header BOOTP / DHCP option 123 Data :::

BOOTP / DHCP option 123:

0001020304050607 0809101112131415 1617181920212223 2425262728293031
Code Length LaRes Latitude
Latitude LoRes  
Longitude
AT AltRes Altitude
  Datum Data :::

Code. 8 bits. Always set to 123.
Option code.

Length. 8 bits. Always set to 16.
Size of the option data in bytes.

LaRes, Latitude resolution. 6 bits.
The number of high-order Latitude bits that should be considered valid. Any bits entered to the right of this limit should not be considered valid and might be purposely false, or zeroed by the sender.

Latitude. 34 bits, fixed point.
9 bits of integer and 25 bits of fraction. Latitude SHOULD be normalized to within +/- 90 degrees. Positive numbers are north of the equator and negative numbers are south of the equator.

LoRes, Longitude resolution. 6 bits.
The number of high-order Longitude bits that should be considered valid. Any bits entered to the right of this limit should not be considered valid and might be purposely false, or zeroed by the sender.

Longitude. 34 bits, fixed point.
9 bits of integer and 25 bits of fraction.  Longitude SHOULD be normalized to within +/- 180 degrees. Positive values are East of the prime meridian and negative (2s complement) numbers are West of the prime meridian.

AT, Altitude type. 4 bits.

AltRes, Altitude resolution. 6 bits.

Altitude. 30 bits.

Datum. 8 bits.

Data. Variable length.

Glossary:

RFCs:

[RFC 3825] Dynamic Host Configuration Protocol Option for Coordinate-based Location Configuration Information.

Publications:

Obsolete RFCs:

Description Glossary RFCs Publications Obsolete RFCs