# Compression Cassandra’s binary protocol supports optional compression of transport-level requests and responses, for example: * a query with its serialized parameters; * a [page]() from a result set, i.e. a list of serialized rows. It reduces network traffic at the cost of CPU overhead, therefore it will likely be beneficial when you have larger payloads. Two algorithms are available: [LZ4](https://github.com/jpountz/lz4-java) and [Snappy](https://code.google.com/p/snappy/). The LZ4 implementation is a good first choice; it offers fallback implementations in case native libraries fail to load and [benchmarks](http://java-performance.info/performance-general-compression/) suggest that it offers better performance and compression ratios over Snappy. Both rely on third-party libraries, declared by the driver as *optional* dependencies. So if you use a build tool like Maven, you’ll need to declare an explicit dependency to pull the appropriate library in your application’s classpath. Then you configure compression at driver startup. ## LZ4 Maven dependency: ```xml at.yawk.lz4 lz4-java 1.9.0 ``` Always check the exact version of the library: go to the driver’s [parent POM](https://repo1.maven.org/maven2/com/scylladb/scylla-driver-parent/3.11.5.0/scylla-driver-parent-3.11.5.0.pom) (change the URL to match your driver version) and look for the `lz4.version` property. Driver configuration: ```java cluster = Cluster.builder() .addContactPoint("127.0.0.1") .withCompression(ProtocolOptions.Compression.LZ4) .build(); ``` LZ4-java has three internal implementations (from fastest to slowest): * JNI; * pure Java using sun.misc.Unsafe; * pure Java using only “safe” classes. It will pick the best implementation depending on what’s possible on your platform. To find out which one was chosen, [enable INFO logs]() on the category `com.datastax.driver.core.LZ4Compressor` and look for a log similar to this: ```default INFO com.datastax.driver.core.LZ4Compressor - Using LZ4Factory:JNI ``` ## Snappy Maven dependency: ```xml org.xerial.snappy snappy-java 1.1.2.6 ``` Always check the exact version of the library: go to the driver’s [parent POM](https://repo1.maven.org/maven2/com/scylladb/scylla-driver-parent/3.11.5.0/scylla-driver-parent-3.11.5.0.pom) (change the URL to match your driver version) and look for the `snappy.version` property. Driver configuration: ```java cluster = Cluster.builder() .addContactPoint("127.0.0.1") .withCompression(ProtocolOptions.Compression.SNAPPY) .build(); ```