For ISPs, Internet Exchanges (IX) and Large Campus networks, WAN-scale multi-context virtualization offers dynamic creation of logical switches within a physical switch to make programmable network resource allocation possible.
Network hardware virtualization drivers and challenges
Traffic in metro networks is exploding, characterized by many nodes, with varying traffic flows and a wide mix of services and bit rates. To cope with this, WAN and metro networks require network resources that can be adjusted into logical zones; they need the ability to create new services out of pools of network resources. Virtualization is a concept that has achieved this in data centers where compute resources have long been virtualized using virtual machines (VMs). NICs providing network connectivity to VMs have been virtualized. But network resources are still rigidly and physically assigned in metro and WAN networks.
Architects and operators of these networks are confronted with complex networking structures that don’t lend themselves to any form of dynamic change. A further dilemma is that they need to both manage existing connections but also build new platforms that excel at delivering on-demand services and subscriber-level networking. The IXPs and ISPs who architect networks with dynamic programmatic control will achieve service velocity that is winning.
Enter true network hardware virtualization which creates virtual switching and routing instances (VSI) at WAN scale to let operators, or their customers, spin up new services quickly and easily.
Multi-context virtualization in network hardware for WAN and metro networks
Corsa’s SDN data planes let metro and WAN network architects and operators dynamically slice their network hardware into virtual switching and routing instances while experiencing internet-scale throughput. Using open, programmable APIs, it is possible to create logical switches within a physical switch, in order to isolate network resources for different customers, or business use cases needing different policies, all while running on the same, shared infrastructure.
A network operator can create different network zones, for instance external customer, developer or secure zones, running on the same data plane to allow secure zones to exist within a parallel production network. With Corsa’s SDN hardware virtualization capabilities, these virtual switch and router overlays can be provided dynamically and transparently regardless of scale.
Features of Corsa multi-context virtualization
Corsa’s SDN data planes allow network operators to establish in-hardware virtual forwarding contexts (VFCs), such as switching and routing instances, without compromising the performance or reliability of each virtual instance. Each packet is processed with full awareness of which virtual switch instance it belongs to. This level of virtualization is not limited to segmenting the hardware by physical ports, or other resources, but in fact allows an administrator to truly virtualize the whole platform into multiple virtual switch instances that share the same hardware platform and yet are prevented from interfering with each other.
The data planes have the ability to assign not only physical ports to each VFC, but also logical attachment circuits, such as VLANs, MPLS pseudo wires, GRE tunnels, VXLAN tunnels, or other common logical interfaces. This gives Corsa data planes a unique ability to easily control the traffic using OpenFlow, and, at the same time, forward that traffic over existing underlay networks using standard encapsulation and tunneling protocols, without having to deal with OpenFlow complexity of defining and managing those tunnels.
This level of hardware virtualization allows building traditional Layer 2 and Layer 3 services with new innovative SDN enabled capabilities. For example, an SDN enabled Layer 2 VPLS service can provide SDN enabled features such as Bandwidth on Demand, or application controlled forwarding rules, and at the same time use existing network infrastructure in the underlay (physical) network to provide connectivity for the new service. To further differentiate, service providers may even allow customers to bring their own SDN controllers to control their services, while retaining full control over the underlay network.
With Corsa’s SDN approach to virtualization combined with our advanced traffic engineering capabilities, bandwidth can be allocated to logical switch instances as needed based on the hardware owner’s specification. The logical ports added to each VFC are shaped to the required bandwidth, and can be allocated to any physical port of any speed. For example a single logical port that belongs to one VFC can be assigned to the same physical port as another group of logical ports that belong to a different VFC. All these logical ports can vary in bandwidth allocation as per the requirements of the service. Furthermore, the logical port numbers can be the same between all VFCs, so the service would not require any port number changes if it was moved to a different VFC. This results in improved efficiency in using port and bandwidth resources, as well as improved user and operator experience for guest controllers connected to virtual switch instances.
With Corsa SDN hardware virtualization, virtual switching and routing can be achieved at scale to enable programmable, on-demand services for operators and their customers.