Ryu consists of a wide range of libraries that support southbound protocols and packet processing. Some of the southbound protocols include:

• OF-Config, which is a protocol designed for OpenFlow switch management. It performs a collection of the settings and status of the logical switches, ports, and queues.
• XFlow, which consists of NetFlow and sFlow. sFlow is primarily used to parse an sFlow packet from Open vSwitch. NetFlow and sFlow protocols are primarily network traffic management tools used for packet sampling and aggregation.
• OVSDB, which is primarily used to permit remote management of network nodes.

The Ryu packet library helps you to parse and build various protocol packets, such as VLAN, Multiprotocol Label Switching (MPLS), and Generic Routing Encapsulation (GRE).

Third-party libraries also do exist. The Oslo configuration library (ryu.contrib.oslo.config) is one example which is used for the configuration of files and the command-line interface of the Ryu manager.