June 14, 2019: protobuf-2.5.0-1.el7.x86_64.rpm - Removed: Provided by CentOS/RHEL.
April 7, 2014: protobuf{,-compiler,-devel,-lite,-lite-devel,-lite-static,-python,-static,-vim}-2.4.1-1.el6.x86_64.rpm - Protobuf (Protocol Buffers)
are a way of encoding structured data in an efficient yet extensible format. Google uses Protocol Buffers for almost all of its internal RPC protocols and file formats.
This package was only provided for CentOS/RHEL 6 for the x86_64 architecture.