SDN - Software Defined Networking
Is interesting when want study SDN that to know about some protocols. The SDN is a proposal that separates two layers: software control and hardware datapath. In this case, is essential analyze the management protocols like CLI, SNMP and routing protocols like OSPF, ISIS and BGP.
With relationship to management protocols, CLI (Command Line Interface) [1] is the way that provides mechanisms to install, manipulate, and delete the configuration of network devices. SNMP (Simple Netwotk Manager Protocol) [2] is used to communicate managemen information between the network management stations and the agents in the network elements and relies in two implementations: MIB (Management Information Base), the set of managed objects, which seeks to include all information necessary for management of the network, thus enabling the automation of most management tasks and SMI (Structure for Management Information) for use by the managed objects contained in the MIB.
Management protocols have a noble mission to controlling a computer network so that it is possible to maximize efficiency and productivity. OSPF (Open Shortest Path First), [3] distributes routing information between routers belonging to a single Autonomous System with IP packets based solely on the destination IP address found in the IP packet header.
SDN's proposal is that a open-source software controls the network, so will possible create many possibilities for packet forwarding according to the packet priority or characteristics. The expectation is that with an open development, more research in the world can use these solutions, which results in an acceleration in innovation.
[1] http://www.soltech-solutions.com/cli-commands/cisco-cli-commands.html
[2] SNMP. Simple Network Management Protocol. RFC 1157. IETF - Internet Engineering Task Force.
[3] OSPF. Open Shortest Path First. RFC 2328. IETF - Internet Engineering Task Force. April 1998.