Ronja Twibright Labs

Measuring BER with Ronjaping on 2x Metropolis

Bit Error Rate measurement of an installed Metropolis link



  • 2 PC's to which Ronja can be connected
  • Full duplex AUI network cards or Half Duplex Reduction(s)
  • Access to one of the PC's or 3rd PC connected to one side of the link by full-duplex wired or fiber optic network.
  • The PC for measurement must be with Linux and ability to compile C programs


Download and compile Ronjaping

Why running 2 pings at a time

Ronja electronics could have a fault causing crosstalk between the directions which would cause packetloss that would happen only if both directions are loaded simultaneously. We excersise this condition by running two instances of ronjaping simultaneously.

Postscript / PDF / EPS / BIG png / SVG (Inkscape)

Connecting just electronics

If you are testing just bare electronics on the floor, connect the components according to the picture.

IP setup

Set up IP networking. If you are using half duplex reduction to emulate full duplex card, read how to emulate full duplex card on IP level.

Running Ronjaping

Run two instances of ronjaping simultaneously in different xterms or consoles. Replace <other side> with IP address or hostname.

ronjaping -c -l 1472 <other side>
Leave it running long enough. The lower the expected BER is the longer you have to run it.

Read the BER

Press ctrl-c in the instance started later. ronjaping prints out the BER. The precision depends on how long it has been running.
An expected information missing here?