+-----------+
           +  Source   +
           +-----+-----+
                 |
-----------------+----------------------------
                 |eth1/1
             +---+----+
             +  R1    +
             +-+----+-+
        eth1/2 |     \ eth1/3
               |      \
               |       \
               |        \
---------------+---------+--------------------
               |          \
               |           \
     +---------+--+     +---+--------+
     + Receiver 1 +     + Receiver 2 +
     +------------+     +------------+