SDN Control

• OpenFlow (OF) is considered one of the first software-defined networking (SDN) standards. It originally defined the communication protocol in SDN environments that enables the SDN Controller to directly interact with the forwarding plane of network devices such as switches and routers, both physical and virtual (hypervisor-based), so it can better adapt to changing business requirements

https://www.sdxcentral.com/sdn/definitions/what-is-openflow/

• OpenFlow is a communications protocol that gives access to the forwarding plane of a network switch or router over the network. OpenFlow enables network controllers to determine the path of network packets across a network of switches. The controllers are distinct from the switches. This separation of the control from the forwarding allows for more sophisticated traffic management than is feasible using access control lists (ACLs) and routing protocols. Also, OpenFlow allows switches from different vendors — often each with their own proprietary interfaces and scripting languages — to be managed remotely using a single, open protocol. The protocol's inventors consider OpenFlow an enabler of software defined networking (SDN)

https://en.wikipedia.org/wiki/OpenFlow

• Open vSwitch Database (OVSDB) is a management protocol in a software-defined networking (SDN) environment. OVSDB was created by the Nicira team that was later acquired by VMware. Originally, was part of Open vSwitch (OVS), which is a feature-rich, open source virtual switch designed for Linux-based hypervisors. Most network devices allow for remote configuration using legacy protocols, such as simple network management protocol (SNMP). The focus with OVS was to create a modern, programmatic management protocol interface – OVSDB was the answer.

https://www.sdxcentral.com/cloud/open-source/definitions/what-is-ovsdb/

• Valve - Motivations

Valve is a smart OpenFlow switch controller built in Ryu (Valve > Switch > Hub).
Just built SDN testbed at Waikato University
Wanted to bridge it onto a traditional network
Needed to add VLANs to SDN testbed
Thought we would test the theory that SDN enables rapid development/prototyping of new features
https://github.com/openvapour/valve

• Cisco Software-Defined Access (SD-Access) gives you a single network fabric, from the edge to the cloud. You can set policy-based automation for users, devices, and things.

https://www.cisco.com/c/en/us/solutions/enterprise-networks/software-defined-access/index.html

Nuage Networks SDN and SD-WAN products 

What is Nuage Networks VSC?

Overlay SDN Introduction: Nuage Networks VSP Lab Topology with GNS3

Juniper Launches Contrail SDN Software, Goes Open Source

• What is Software-Defined WAN (or SD-WAN or SDWAN)?

The software-defined wide-area network (SD-WAN or SDWAN) is a specific application of software-defined networking (SDN) technology applied to WAN connections such as broadband internet, 4G, LTE, or MPLS. It connects enterprise networks – including branch offices and data centers – over large geographic distances.
https://www.sdxcentral.com/sd-wan/definitions/software-defined-sdn-wan/

• Will P4 replace OpenFlow?

Why Software Defined Networking needs P4
One of the key problems that Software Defined Networking (SDN) community is trying to solve is reducing the  time required to implement new protocols or extend their functionality.

Why your network needs P4
P4 (Programming Protocol-Independent Packet Processors) is a domain-specific language for expressing how packets are processed by the data plane of a programmable forwarding element, such as a hardware or software switch, network interface card, router, or network appliance

Will P4 replace OpenFlow?
OpenFlow is one of the most widespread SDN protocols nowadays. It has an established infrastructure, community and controllers working on top of it. What else  can you wish for? Although it is misleading to think that everyone will ditch OpenFlow and start deploying switches with P4 support in their networks, there is still a few significant drawbacks to OpenFlow that data center people might take into consideration.
https://plvision.eu/rd-lab/blog/sdn/p4-programming-future-sdn