end-to-end principle, packet switching

network layers
   application: HTTP
   (presentation)
   (session)
   transport: UDP, TCP
   network: IPv4, IPv6
   data link: MAC, CSMA, SLIP
   physical

Internet 0
   i0.3.serial.44.cad
   i0.3.serial.44.packetv4.asm
   i0.3.IO.44.cad
   i0.3.IO.44.thtpv4.asm
   thtpv4.py
   i0.3.H-bridge.44.cad
   i0.3.stepper.44.cad
   i0.3.sensor.44.cad

hello worlds