The SDN Architecture is :
1. Directly programmable:
Network control is directly programmable because it is decoupled from forwarding functions.
2. Agile:
Abstracting control from forwarding lets administrators dynamically adjust network-wide traffic flow to must changing needs.
3. Centrally managed:
network intelligence is (logically) centralized in software based SDN controllers that maintain a global view of the network,which appears t applications and policy engine as a single,logical switch.
4. Programmatically configured:
SDN lets network managers configure,manage,secure and optimize network resources very quickly via dynamic,automated SDN programs,which they can write themselves because the programs do not depends on proprietary software.
5.Open standards-based and vendor neutral:
When implemented through open-standards,SDN simplifies network design and operation because instructions are provided by SDN controllers instead of multiple,vendor-specific devices and protocols.