Decoupling the decision-making process from the data forwarding process is the heart of
software-defined networks technology. One of the most important components of this
technology is the controller, which is the smartest component in the network.
Many of the
controllers have been developed since the technology originated, and many researches
have been done to compare the performance of these controllers for productivity, delay and
protection.
And due to the importance of selecting the appropriate controller according to different
parameters and network states, we studied the performance of four controllers: Floodlight,
Beacon, Nox, RYU in terms of productivity, RTT, time of establishing connection with an
OpenFlow switch and the time for adding an input to the switch flow table. The results
showed that the Beacon control was superior in performance when the number of switches
in the network was equal to the number of processor cores used by the controller. For RTT
and the time needed to add an input to the flow table, the NOX controller achieved less
time. Finally, the Floodlight controller was the best in terms of establishing connection
with the switch because it needed less time.
The mapping of Layer 3 (IP) to Layer 2 (MAC) addresses is a key service in IP networks, and is achieved via the Address Resolution Protocol (ARP) protocol in IPv4. Due to its stateless nature and lake of authentication, ARP is an easy goal to spoofin
g attacks, which can enable Denial of Service (DoS) or Man-in-the-Middle (MIM) attacks. In this search, we discuss the problem of ARP spoofing in the context of Software Defined Networks (SDNs). We studied important parameters such as throughput, delay and the availability of the network. Results showed that ARP spoofing attacks was able to make a negative effects on network performance
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.
