When IBM launched its OpenDaylight Hydrogen-based SDN controller this week, it was only an early part of a longer-term, software-driven data center strategy that will stretch orchestration across networks, compute and storage.
IBM, a key contributor to OpenDaylight, announced its controller in conjunction with the consortium's release of the Hydrogen open source SDN code for download. IBM's controller will be central to its Software Defined Networks for Virtual Environments (SDN VE) ecosystem.
IBM SDN VE, originally called Distributed Overlay Virtual Environment (DOVE), lets users create VXLAN-based virtual networks on top of legacy hardware equipment. The virtual overlays consist of a centralized controller and distributed virtual switches. A series of overlay gateways link these virtual networks to underlying physical networks.
IBM uses the term ‘unified controller’ because the Hydrogen release will allow for tighter control across apps and flows on both physical and virtual networks at once.
Now IBM will replace its DOVE controller with the Hydrogen controller, which will allow for use of OpenFlow 1.3 in multi-vendor physical and virtual networks, and will bring a wider range of network services to IBM's virtual environments, said Inder Gopal, IBM vice president of System Networking Development. The new release also adds support for Linux-based KVM hypervisors and Open Virtual Switches. DOVE worked only in VMware environments.
"Hydrogen has is a very broad and extensible framework … that allows you to plug in a bunch of services and various southbound protocols, and we are porting all the DOVE functions onto that," Gopal said.
IBM uses the term "unified controller" because the Hydrogen release will allow for tighter control across apps and flows on both physical and virtual networks at once. With an OpenFlow 1.3 plug-in, for example, the controller can manage flows across OpenFlow-friendly hardware switches in addition to virtual switches on hypervisor hosts. The controller can also integrate physical and virtual network services appliances.
"You can control many more apps in the network and you have the ability to control virtual and physical and forwarding tables and routing tables. We can think of many use cases where customers may want to do one or do them in combination," Gopal said.
However, IBM is likely trying to head off criticism that overlay networks aren't integrated tightly enough with physical networks, causing problems for network engineers. Cisco has blasted VMware for this issue.
Like many virtualization providers, IBM is also touting partnerships with multiple network application/service vendors that will allow users to integrate network services into the new controller. Partners include A10 Networks, Brocade, Palo Alto Networks, Silver Peak and many others.
"We will have guys building security apps and load-balancing apps and a variety of other network services," Gopal said. In some cases, these will be built into the controller and in other cases they will be virtual appliances that are directed by the controller.
IBM's SDN VE already integrates into OpenStack orchestration, bringing network provisioning into the overall automation scenario.
Next up, IBM will focus efforts on software-defined storage and compute, Gopal said. Ultimately, the plan will be to "orchestrate across siloes," he said.
"You will define what you want out of the infrastructure in one place and then map that definition into what compute and storage and networks need to do," he said.