Hi, I am using TCPServer() abstraction with Photon to send the around 448 bytes of data to the connected client at every 64ms. But when I verify all the packets on the client side, I found few packets were missed. And after debugging I found the loss happens on Server side!! Is there any limitatio…

Hi, I have done one more experiment. Run the server on the PC and tried to send the data to the same client at the same frequency i.e. 448 bytes at every 64ms. But there was no packet loss. So it seems there is something wrong with TCPServer() abstraction or I am not using it correctly!! Please h…

Can someone please help me here?

Yes there is a limitation due to limited default RX buffer size of the device. If your code does not ensure to keep the buffer below a certain high water mark, your buffer might wrap round overwriting not yet read data. This has nothing to do with the TCP “packet safety”, since you are not actuall…

Hi @ScruffR , Thanks for your reply! I am not receiving any data on TCP, I am just sending data over TCP to the connected client. So how does the RX buffer size affecting it? And what is the hight water mark value for the buffer? I have to send the data at the specified rate, so that can’t be chan…

Ah, sorry - misinterpreted the communication direction. In this case my question would be, if you really are loosing packets or are they just never sent in the first place? Keeping a precise timing is not always easy with WiFi and cloud involved. You could go with SYSTEM_MODE(SEMI_AUTOMATIC) to k…

Hi @ScruffR , I think the packets were never sent over the network and we have verified this using Wireshark packet capture. Ans also there is not scope of loosing packets over the network with TCP! I am sending the packets in the local network, so I think cloud and probably WiFi should not be the …

[image] dhaval: I think cloud and probably WiFi should not be the issue If you are running default SYSTEM_MODE(AUTOMATIC) the cloud will add some latency between iterations of loop(). This should be in the 1ms range, but depending on your global location it could be more. But for tracking do…

Hi @ScruffR , I have tried to increase the TCPCLIENT_BUF_MAX_SIZE to 2048, but still observe the packet loss!! Also tried after adding SYSTEM_MODE(AUTOMATIC), but no improvement. What is restricting to send the data even in the local network? Thanks, Dhaval

[image] dhaval: Also tried after adding SYSTEM_MODE(AUTOMATIC), but no improvement. Actually I meant you might consider not to use AUTOMATIC since it might contribute to your problem. Try SEMI_AUTOMATIC instead.

[image] dhaval: Also tried after adding SYSTEM_MODE(AUTOMATIC), but no improvement. By mistake I mentioned AUTOMATIC, actually I used SEMI_AUTOMATIC. But I didn't see any improvement. Also after doing that I face some difficulties to re-program new application using Web IDE.

TCPServer() usage and bandwidth issue

Firmware

ScruffR May 26, 2016, 8:16pm 15

I remember @rickkas7 whipping up a nice bulk transfer sketch. Maybe he can chime in here.

or see

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TCPServer() usage and bandwidth issue

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