  Network measurement probes the underlying network to support upper-level
decisions such as network management, network update, network maintenance,
network defense and beyond. Due to the massive, speedy, unpredictable features
of network flows, sketches are widely implemented in measurement nodes to
approximately record the frequency or estimate the cardinality of flows. At
their cores, sketches usually maintain one or multiple counter array(s), and
rely on hash functions to select the counter(s) for each flow. Then the
space-efficient sketches from the distributed measurement nodes are aggregated
to provide statistics of the undergoing flows. Currently, tremendous redesigns
and optimizations have been proposed to improve the sketches for better network
measurement performance. However, existing reviews or surveys mainly focus on
one particular aspect of measurement tasks. Researchers and engineers in the
network measurement community desire an all-in-one survey that covers the
entire processing pipeline of sketch-based network measurement. To this end, we
present the first comprehensive survey of this area. We first introduce the
preparation of flows for measurement, then detail the most recent
investigations of design, aggregation, decoding, application and implementation
of sketches for network measurement. To summarize the existing efforts, we
carry out an in-depth study of the existing literature, covering more than 90
sketch designs and optimization strategies. Furthermore, we conduct a
comprehensive analysis and qualitative/quantitative comparison of the sketch
designs. Finally,we highlight the open issues for future sketch-based network
measurement research.
