0

I use CoAP ( write by C) to FOTA multicast but It timeout. I use unicast it still work done.

p/s:Sorry I use English don't well. link source lib-coap: https://github.com/obgm/libcoap image error: enter image description here

How to fix it. Thanks.

I tried unicast and I want to use for multicast. But it don't work.

Ngô Cường
  • 1

1 Answers1

0

Using CON messages, CoAP adds "reliability" on the top of UDP. But for multicast UDP, this doesn't work. Otherwise, you would need to know, how many devices are used. RFC 7252 doesn't specify that use-case. Multicast is also mostly limited to local-networks, it's very useful to discover the devices there, but not for FOTA. That kind of optimizations usually don't pay off.

Achim Kraus
  • 729
  • 1
  • 7
  • 11