  The CMS beam and radiation monitoring subsystem BCM1F (Fast Beam Condition
Monitor) consists of 8 individual diamond sensors situated around the beam pipe
within the pixel detector volume, for the purpose of fast bunch-by-bunch
monitoring of beam background and collision products. In addition, effort is
ongoing to use BCM1F as an online luminosity monitor. BCM1F will be running
whenever there is beam in LHC, and its data acquisition is independent from the
data acquisition of the CMS detector, hence it delivers luminosity even when
CMS is not taking data. A report is given on the performance of BCM1F during
LHC run I, including results of the van der Meer scan and on-line luminosity
monitoring done in 2012. In order to match the requirements due to higher
luminosity and 25 ns bunch spacing, several changes to the system must be
implemented during the upcoming shutdown, including upgraded electronics and
precise gain monitoring. First results from Run II preparation are shown.
