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HLS CTOS understanding

By mehul.makwana , 19 June, 2023
Forums
General discussion

I've HLS as "77777777777777777777777777777777" in hex "wwwwwwwwwwwwwwww" in ASCII but when I send via gurux or any other meter reading software i.e. kalki, the CallingAuthentication Value changed it into "0F286E004D6C3C291564560557271D11". I know its a CtoS challenge for pass1 but how hls is converted to this string, or I should say from which encryption method it is encrypted that I didn't understand. I'm trying to establish client id 48 of a smart energy meter. and If any one can provide me a document where after pass1, how to create data for pass3 then it would be very handy. thanks in advance.

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Kurumi

2 years 11 months ago

Hi, This is described in the…

Hi,

This is described in the Green Book. In short, the meter sends a challenge to the client that the client encrypts with the secret and then sends it back to the server as a CtoS.

The meter does the same for the client challenge.

BR,
Mikko

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