SMS Data encoding

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K9JPT
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Joined: Fri Apr 24, 2020 10:11 am

SMS Data encoding

Post by K9JPT » Fri Oct 16, 2020 11:30 am

Per SMS this would follow the DMR standard and not a Radioddity, Motorola or Hytera proprietary standard correct?

K9JPT
Posts: 45
Joined: Fri Apr 24, 2020 10:11 am

SMS Data encoding

Post by K9JPT » Fri Oct 16, 2020 11:49 am

I found a small part in the ETSI technical spec that states the following on SMS encoding:

https://www.etsi.org/deliver/etsi_ts/10 ... 10201p.pdf

Page 35

ETSI ETSI TS 102 361-3 V1.2.1 (2013-07)355.7.1 Text Messaging Text messaging shall utilize UTF-16BE [15] character encoding in plane 0, the Basic Multilingual Plane or BMP. It should use a default radio network UDP Port of 5016. It is recommended that the UDP Port be configurable to address conflicts when connecting into an already established network.

VK3KYY
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Re: SMS Data encoding

Post by VK3KYY » Fri Oct 16, 2020 9:30 pm

The encoding you are referring to is in a section called

Application Data over IP Bearer Service

This is not the "On Air" protocol or encoding.

The ETSI standard has multiple documents with many sections and a lot of it does not apply to the transmissions which are sent via RF.

The reference you found is the Internet networking transfers

And UTF-16 in general, is not an 'encoding' in the same, way for example Golay or Huffman etc, as used for over the air communications.
Its more of a data length, than an encoding. i.e 2 bytes per character.


BTW.
Systems like Brandmeister, don't use the ETSI DMR Internet protocols, they just wrap the raw , "On Air" data, with their own header, and pass it without converting to and from the ETSI Internet protocol standard.

The MMDVM and Jumbospot style modems are effectively very dumb, they just decode / encode the 4FSK data stream them, and pass it to MMDVMHost which wraps the raw data with the header and sends it off.

Actually MMDVMHost does error check the data etc, and parse for frame type information etc, but it does not do protocol conversion.

VK3KYY
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Re: SMS Data encoding

Post by VK3KYY » Fri Oct 16, 2020 9:33 pm

K9JPT wrote:
Fri Oct 16, 2020 11:30 am
Per SMS this would follow the DMR standard and not a Radioddity, Motorola or Hytera proprietary standard correct?
I've no idea.

Radioddity won't have their own standard, and actually Radioddity are not really even a manufacturer, they are just a rebranding company for TYT, in the same way that Retevis is also rebranding company for TYT.

I have been told that Motorola and the other manufacturers may have their own private standards for SMS, and I suspect that the official GD77 firmware probably uses whatever protocol that Motorola use, but this has never been verified

K9JPT
Posts: 45
Joined: Fri Apr 24, 2020 10:11 am

Re: SMS Data encoding

Post by K9JPT » Thu Oct 22, 2020 12:44 pm

Thank you for taking the time to explain this further. SMS would be great if it can work across multiple brand radios. But then again if OPEN GD77 has large enough following maybe only amongst users would work too?

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