الشبكات المعرفة برمجيا SDN هي عبارة عن بنية شبكية جديدة توفر التحكم المركزي بكامل الشبكة. يعمل هذا المتحكم كنظام تشغيل يقوم بإرسال التعليمات وتطبيق التغييرات من خلال الواجهات التخاطبية بينه وبين الأجهزة المسؤولة عنها ويدعى بالمتحكم.
Software Defined Networks (SDN) is the qualitative movement in the field of networks due to that fact that it separates the control elements from the routing elements, and the function of the routing elements was limited to the implementation of the
decisions that are sent to it by the controller through the OpenFlow Protocol (OF) which is mainly used in SDN. We explain in this paper the benefit of the new concept which is presented by SDN and it makes network management easier, so instead of writing the rules on each device, we program the application in the controller, and the infrastructure devices run the received commands from the controller. In order to achieve the best performance of this technology, a Quality of Service (QoS) must be applied within it, where it includes several criteria, the most important are the used bandwidth, delay, packet loss and jitter. The most important of these criteria is the bandwidth, because by improving this standard, we can improve the rest of the other criteria. Therefore, in this paper, we provide the necessary improvement on the RYUcontroller to use the best bandwidth, which improves the quality of service in SDN.
ASON\GMPLS based optical network technology has shown high reliability recently, but the issue of unified control of optical networks has become an urgent necessity to cover problems caused by separate control between different optical network layers
. The attempt to implement GMPLS-based standardized control of Internet Protocol / Dense Wavelength Division Multiplexing (IP/DWDM) networks has yielded satisfactory results but reflected significant complexity when operating in real time. On the other hand, the OpenFlow control level is offered as a promising solution to be a uniform control level for such networks, but it is not yet effective enough to control optical switch nodes. Therefore, as an intermediate step towards a unified UCP level entirely based on the OpenFlow protocol, the logical thinking for the time being is to introduce an OpenFlow/GMPLS interoperability control level that uses GMPLS to control the optical layer and the dynamic coordination between the IP layer and the optical layers. This research presents a practical application of interoperability solutions (parallel, overlapping, and integrated) for GMPLS and OpenFlow control levels applied to the ASON optical network installed in the southern region of Syria. The results have shown that the integrated solution for uniform control is superior to parallel and overlapping solutions in terms of the overall path provision latency (OPPL), at the expense of the high complexity of the design and processing of the load within the controller.
