Server GPS forwarding problem NMEA

Hello,
I’m currently working on a server coded in java that receives NMEA frames from peplinks and stocks on a MariaDb database on rapsberry. I use the gps forwarding function of the peplinks. I use tcp to ensure that I receive my frames. Everything works, the problem is that sometimes the sentences in the frames are out of order, I thought tcp guaranteed the correct transmission.

Example, Frame 1 (good frame):
$GPGSV,4,1,13,08,38,302,25,10,56,120,28,11,16,270,27,16,60,199,2174
$GPGSV,4,2,13,18,17,057,26,20,45,064,23,21,70,274,27,23,24
43
$GPGSV,4,3,13,26,27,171,31,27,71,333,26,07,09,306,15,03,039,*7A
$GPGSV,4,4,13,30,*78
$GPGGA,081247.0,4329.020981,N,00532.408537,E,1,09,0.7,185.9,M,49.0,M,55
$GPRMC,081247.0,A,4329.020981,N,00532.408537,E,0.0,292.7,020920,0.9,W,A
16

Example, Frame 2 (bad frame):
$GPGSV,4,2,13,18,17,057,26,20,45,064,25,21,70,274,26,23,22*42
$GPGSV,4,3,13,26,27,171,30,27,71,333,27,07,09,306,15,03,039,*7A
$GPGSV,4,4,13,30,78
$GPGGA,081252.0,4329.020983,N,00532.408537,E,1,09,0.7,185.9,M,49.0,M,53
$GPRMC,081252.0,A,4329.020983,N,00532.408537,E,0.0,292.7,020920,0.9,W,A
10
$GPGSV,4,1,13,08,38,302,25,10,56,120,27,11,16,270,26,16,60,199,20
7B

I put screenshot in an attached file, for a better understanding of my problem.
What do you think?

Due to COVID-19 I recommend to use UDP as to avoid the handshakes.

Wear your mask in public!

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AHAHAH very fun ! I really need a solution about that because my server doesn’t works.The tcp protocol is not respected, i.e. parameters such as the sequence number are initialized to ensure reliable lossless and orderly transmission of data.The wireshark screenshot shows that the frame arrives in disorder.

Hi Saleph,

I would open a Ticket and enable RA. Then the Support-Team can help you. You can refer to this article and Post the Ticketnumber here.

Good Luck
Dennis

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Thanks for ur answer Dennis, What’s RA ?
Sebastien.

Thats Remote Assistance

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