recommended for a small number of connections (< 1000). org.jboss.netty.handler.codec.compression Encoder and decoder which compresses and decompresses ChannelBuffer s in a compression format such as zlib and gzip . org.jboss.netty.handler.codec.http.websocketx Encoder, decoder, handshakers and their related message types for Web Socket data frames. org.jboss.netty.handler.ipfilter Implementation of a Ip based Filter handlers.