Software Defined Network

Software Defined Network (SDN)

A Software defined network or SDN is a technology for virtualizing the network layer and network management systems. Basically, it is a centralized architecture and useful at Data Centre devices, wide area network devices and large campus networks. 

We can virtualize a network so that can break the direct connection between our applications and virtual servers as well as our physical network. It is possible to manage a virtualized network infrastructure by providing the tools to configure virtual network objects and policies. We have the network controller which provides centralized management, configuration, monitoring, and troubleshooting of both our virtual and physical network infrastructure. The SDN Applications or programs explicitly, directly, and programmatically communicate their network requirements and desired network behaviour to the SDN Controller via a northbound interface (NBI). The SDN Controller is nothing but one software or application to manage the SDN.

The Hyper-V Network Virtualization which helps to extract applications and capacities from the underlying physical network by using virtual networks. Hyper-V Virtual Switch which offers the ability to connect virtual machines to both the virtual networks and the physical networks as well as security, isolation and service level policy enforcement. 

It is an advanced architecture and is manageable, cost-effective, and dynamic. It is ideal for today’s applications due to its high bandwidth.

If we discuss about CISCO, it comes with Cisco ACI and industry leading SDN solution for Data Centres. It provides automation, consistency, multi cloud acceleration, container integration and zero trust network protect. In addition to those it also provides Data Centre Network assurance and Insights. 

In SDN technology, open flow protocol is used for communication that gives access to the forwarding plane of a network switch or router over the network. 

The SDN architecture can be;

• Directly programmable
• Centrally managed
• Open standard

Some of the SDN Controller features:

SDN controller have many important features which needs to be considered while deployed. Here are some of the features mentioned below;

• The SDN solution shall support centralized management through Declarative Policy Engine or SDN Controller and it shall program all the networking policies consistently across any workload in physical and virtual environments.
• The SDN Solution shall automate networking policies and service overlay provisioning for the Bare metals, Virtual Machines.
• The SDN Solution shall support Overlay VXLAN, Geneve or equivalent tunnel.
• The solution shall provide integration with cloud management systems using open interfaces like RESTAPI or equivalent.
• Centralized management appliance or SDN Controller must support multi tenancy from management perspective and provide Role Based Access Control per tenant for the tenant management.
• SDN Controller shall provide dynamic device inventory of the Fabric as well as current network topology of the fabric. It must also validate the cabling connectivity and generate alarms in case of wrong or faulty connectivity.
• The SDN solution shall support granular role-based access control policies and support AAA using Local User authentication/ External RADIUS/External TACACS+ protocols.

-DR