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PaulStoffregen / Ethernet

Ethernet library for Teensy (Wiznet W5100 / W5200 / W5500)
http://www.pjrc.com/teensy/td_libs_Ethernet.html
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Lengthy delay when sending UDP to offline devices on a LAN #25

Open PaulStoffregen opened 6 years ago

PaulStoffregen commented 6 years ago

When sending to an IP number on the same LAN which is offline, users report lengthy delays.

https://forum.pjrc.com/threads/30473-Timeout-delay-in-sendUDP-in-endPacket-when-target-is-not-online

PaulStoffregen commented 6 years ago

Pretty sure this only happens when sending to IP numbers in the same subnet (devices directly reachable on the local LAN) where we need to get a reply to an ARP query to find the 6 byte destination mac address.