h1. Ryu


h2. About
* Network opearting system
* OVS, openflow switch
* python
* www.osrg.net/ryu


h2. Network management applications on top of Ryu (inside a controller node)

* GRE tunneling
* VLAN support
* topology discovery
* MAC based segregation

'Only commodity hardware'


h2. Ryu <--> OpenStack

* Flat networks regardless of the underlying physical network
* Scalable multi-tenant isolations
** tunneling based isolations
** VLAN does not scale larger than 4096
** do not need high-end switches
* Future items:
** integration with quantum IPAM and L3 API
** firewall
** virtual network <--> physical network
** distributed controllers (redundancy)

Quantum plugin for each network technology


h2. Communication

'nova requests quantum-server for network configuragion'

OVS <--> Ryu: openflow

Ryu agent <--> Ryu: REST API

Quantum server <--> Ryu: REST API

Ryu agent <--> Quantum db: db access

VIF driver <--> quantum: Quantum API
linux_net driver <--> server: Quantum API


h2. Network Creation (network-node = nova-network + linux_net driver + OVS)

# to nova-network: create netork
# nova network --> quantum server: create net
# quantum server --> Ryu: network <uuid>, <tunnel key>
# quantum server --> nova network: <uuid>
# nova network --> linux_net driver: plug
# linux_net driver --> OVS: create gw-xxx
# linux_net driver --> quantum server: tentant id, network id, dp id, port, mac
# quantum server --> Ryu: network id, dp id, port, mac
# ryu --> OVS:  set flow entryies


h2. Instance creation (compute-node = nova compute + VIF driver + OVS)

# to nova compute: create instance
# nova compute --> quantum server: create port
# quantum server --> nova compute: uuid
# nova compute --> VIF driver: plug
# VIF driver --> OVS: create tap-xxx
# VIF driver --> quantum server: (tenant_id, dp_id, port, mac)
# quantum server --> Ryu: (network_id, dp_id, port, mac)
# Ryu --> OVS: set flow entryies


h2. Node boot up (compute/network-node = OVS + Ryu agent + ryu_v2.ini)

# ryu_v2.ini --> Ryu agent: get ip address
# Ryu agent -->  quantum db: register (dp_id, ip_address)
# quantum db --> Ryu agent: get list of (dp_id, ip_address, and polling)
# Ryu agent --> OVS: create vport_grc to ip address
# Ryu agent --> Ryu: register (dp_id, port_id, remote dp_id)


h2. Component: separation unit

*  interface for control and states and generates events
*  communicate by message passing
*  language independency

h2. OBS:

two ways oto isolate tenants: GRE tunnel and VLAN