OpenTRAC proposals
The following are a few proposals for the OpenTRAC specification.
(see: www.opentrac.org)
As such there is no guarantee that they will ever get any status beyond
a proposal, so use with care.
A new element for requesting a digipeater path
0x23
Path Request
A station may include this element to request a path for its frame.
This element may only occur once in a frame.
| Path Request |
|---|
| relay request |
relay done |
wide request |
wide done |
latitude |
longitude |
course |
| 1 bit |
1 bit |
3 bit |
3 bit |
32 bit |
32 bit |
16 bits |
| boolean |
boolean |
integer |
integer |
integer |
integer |
integer |
If the relay request bit is set and the relay done bit is not
all stations receiving this packet should digipeat this frame with the
relay done bit set. If the wide done value is less than the
wide request value a wide digipeater may digipeat this rame with
the wide done value incremented.
A wide digipeater must ignore the relay request bit and always set the
relay done bit.
It is recommended to only use wide request values up to and including
3 as this is more then sufficient for a wide coverage.
When the optional fields latitude and longitude are present
a digipeater should only digipeat a frame if its distance to the reported
object is larger than the distince between the given coordinates and the
reported object, thus ensuring an outward digipeating direction.
The presence of these two fields implies the presence of a position element.
The originating station may leave these fields blank (zero) and digipeaters
that do not support this option or don't know their own position must
leave it untouched.
When the optional field course is present a frame should only be
digipeated if the distance is greater in the direction specified by
this field.
Status: Comments requested, reference implementation done
0x24
Specific Path Request
A station may include this element to request a path for its frame.
This element may only occur once in a frame.
| Specific Path Request |
|---|
| Last |
callsign/SSID |
network |
repeat 0 or more times |
| 1 octet |
6 octets |
1 octet |
| integer |
ASCII |
integer |
If the originating station has sufficient knowledge about the network
that it can specify the path for the frame it may use this element.
Each callsign and network pair indicates a hop. If the specified digipeater
receives this frame it can use the network byte as a guide to send it out
on the specified network.
Last should be set to zero by the originating station, each
digipeater should ignore all callsign/network entries lower or
equal to last (counting starts at 1) and on transmit set last to the
number of the entry it responds to.
This frame is primarily intended to be used by stations responding on a
query from another station by using the path trace element in the request
frame. It is thus asumed that the network topology has been static between
query and response.
Status: Comments requested, reference implementation done
A method for transporting OpenTRAC data over DRL
More information about DRL can be read