decred.org/dcrd/gcs (go): Package gcs provides an API for building and using a Golomb-coded set filter.  A Golomb-coded set is a probabilistic data structure used similarly to a Bloom filter.  A filter uses constant-size overhead plus on average n+2 bits per item added to the filter, where 2^-n is the desired false positive (collision) probability.  GCS filters are a mechanism for storing and transmitting per-block filters.  The usage is intended to be the inverse of Bloom filters: a consensus-validating full node commits to a single filter for every block and serves the filter to SPV clients that match against the filter locally to determine if the block is potentially relevant.  The suggested collision probability for Decred use is 2^-20.
Keywords: blockchain|cryptocurrency|dcrd|decred|decred-daemon|decred-nodes|go|golang|p2p|peer-to-peer