ller Flags: Modifying the management way of flow entries As soon as packets arrive from switch port, flow entries compare the packets with match fields. If the packet match found, then only packets will be processed according to the given set of instruction. Major Obstacles faced by OpenFlow are: Performance: This can be improved by pre-occupying the flow tables at the boot time or at the time of policy creation in a proactive manner as an alternative for reacting packets in events. Scale: This can be improved by defining Flow Rule Allocation. Risk: This can be reduced by introducing Hybrid Architecture which supports both OpenFlow enabled devices and legacy network devices. HYBRID MODELS Hybrid Working Group is created by Open Network Foundation. This group only focuses on developing Hybrid model. Ships in the Night (SIN) model architecture is proposed by this group and was approved by the ONF board. Assumption of controlled points between the native controllers and OpenFlow is the new invention in networking elements, the security is the major issue about how the reserved ports could be utilized, SO that, to allow access to native processes on the native network or on the hybrid applications of controller side or OpenFlow ports spoofing IGP peers and other protocol sessions to insert or to attain states. Ships in the Night (SIN) Model The SIN model theory presumes that a physical or logical port can only be used either for native or OpenFlow, but not for both simultaneously. Since, switches conventionally have control plane, SO OpenFlow controller manages only trunked links port or VLANs. The local control plane can perform the large tasks periodically likerunning LACP, LLDP and BFD, and passes link only to the OpenFlow controller, which also resolves the communication problem between controllers and switches. The SIN mainly focuses on: Vaulting the resources which are allocated to the OpenFlow process and such that they could not obstruct the native side operations and vice versa. Downloaded 4/15/2022 9:44:49 