InfiniBand is a switched fabric interconnect. The InfiniBand specification
does not define an API. However the OFED package, libibverbs, has become the
default API on Linux and Solaris systems. Sparse documentation exists for the
verbs API. The simplest InfiniBand program provided by OFED, ibv_rc_pingpong,
is about 800 lines long. The semantics of using the verbs API for this program
is not obvious to the first time reader. This paper will dissect the
ibv_rc_pingpong program in an attempt to make clear to users how to interact
with verbs.