+-----------+
           +  Source   +
           +-----+-----+
                 |
-----------------+----------------------------
                 |eth1/1
             +---+---+
             +  R1   +
             +-+---+-+
        eth1/2 |    \ eth1/3
               |     \
               |      \
               |       \
               |        \
        eth2/1 |         \ eth3/1
           +---+---+   +--+---+
           +  R2   +   +  R3  +
           +---+---+   +--+---+
        eth2/2 |          | eth3/2
               |          |
---------------+----------+-------------------
               |          |
               |          |
      +--------+--+   +---+--------+
      + Receiver1 +   +  Receiver2 +
      +-----------+   +------------+