SDN/NFV-enabled satellite communications networks: opportunities, scenarios and challenges

In the context of next generation 5G networks, the satellite industry is clearly committed to revisit and revamp the role of satellite communications. As major drivers in the evolution of (terrestrial) fixed and mobile networks, Software Defined Networking (SDN) and Network Function Virtualisation (NFV) technologies are also being positioned as central technology enablers towards improved and more flexible integration of satellite and terrestrial segments, providing satellite network further service innovation and business agility by advanced network resources management techniques. Through the analysis of scenarios and use cases, this paper provides a description of the benefits that SDN/NFV technologies can bring into satellite communications towards 5G. Three scenarios are presented and analysed to delineate different potential improvement areas pursued through the introduction of SDN/NFV technologies in the satellite ground segment domain. Within each scenario, a number of use cases are developed to gain further insight into specific capabilities and to identify the technical challenges stemming from them.Peer ReviewedPostprint (author's final draft

Rapidly IPv6 multimedia management schemes based LTE-A wireless networks

Ensuring the best quality of smart multimedia services becomes an essential goal for modern enterprises so there is always a need for effective IP mobility smart management schemes in order to fulfill the following two main functions: (I) interconnecting the moving terminals around the extended indoor smart services. In addition, (II) providing session continuity for instant data transfer in real-time and multimedia applications with negligible latency, efficient bandwidth utilization, and improved reliability. In this context, it found out that the Generalized Multi-Protocol Label Switching (GMPLS) over LTE-A network that offers many advanced services for large numbers of users with higher bandwidths, better spectrum efficiency, and lower latency. In GMPLS, there is an elimination of the routing searches and choice of routing protocols on every core LTE-A router also it provides the architecture simplicity and increases the scalability. A comparative assessment of three types of IPv6 mobility management schemes over the LTE-A provided by using various types of multimedia. By using OPNET Simulator 17.5, In accordance with these schemes, it was proven that the IPv6-GMPLS scheme is the best choice for the system's operation, in comparison to the IPv6-MPLS and Mobile IPv6 for all multimedia offerings and on the overall network performance

Auto-bandwidth control in dynamically reconfigured hybrid-SDN MPLS networks

The proposition of this work is based on the steady evolution of bandwidth demanding technology, which currently and more so in future, requires operators to use expensive infrastructure capability smartly to maximise its use in a very competitive environment. In this thesis, a traffic engineering control loop is proposed that dynamically adjusts the bandwidth and route of flows of Multi-Protocol Label Switching (MPLS) tunnels in response to changes in traffic demand. Available bandwidth is shifted to where the demand is, and where the demand requirement has dropped, unused allocated bandwidth is returned to the network. An MPLS network enhanced with Software-defined Networking (SDN) features is implemented. The technology known as hybrid SDN combines the programmability features of SDN with the robust MPLS label switched path features along with traffic engineering enhancements introduced by routing protocols such as Border Gateway Patrol-Traffic Engineering (BGP-TE) and Open Shortest Path First-Traffic Engineering (OSPF-TE). The implemented mixed-integer linear programming formulation using the minimisation of maximum link utilisation and minimum link cost objective functions, combined with the programmability of the hybrid SDN network allows for source to destination demand fluctuations. A key driver to this research is the programmability of the MPLS network, enhanced by the contributions that the SDN controller technology introduced. The centralised view of the network provides the network state information needed to drive the mathematical modelling of the network. The path computation element further enables control of the label switched path's bandwidths, which is adjusted based on current demand and optimisation method used. The hose model is used to specify a range of traffic conditions. The most important benefit of the hose model is the flexibility that is allowed in how the traffic matrix can change if the aggregate traffic demand does not exceed the hose maximum bandwidth specification. To this end, reserved hose bandwidth can now be released to the core network to service demands from other sites

Hybrid SDN Evolution: A Comprehensive Survey of the State-of-the-Art

Software-Defined Networking (SDN) is an evolutionary networking paradigm which has been adopted by large network and cloud providers, among which are Tech Giants. However, embracing a new and futuristic paradigm as an alternative to well-established and mature legacy networking paradigm requires a lot of time along with considerable financial resources and technical expertise. Consequently, many enterprises can not afford it. A compromise solution then is a hybrid networking environment (a.k.a. Hybrid SDN (hSDN)) in which SDN functionalities are leveraged while existing traditional network infrastructures are acknowledged. Recently, hSDN has been seen as a viable networking solution for a diverse range of businesses and organizations. Accordingly, the body of literature on hSDN research has improved remarkably. On this account, we present this paper as a comprehensive state-of-the-art survey which expands upon hSDN from many different perspectives

Implementación de una red híbrida SDN/MPLS para la gestión de servicios diferenciados mediante simulación de tiempo real GNS3

Desarrollar una red híbrida SDN/MPLS que permita el análisis de su comportamiento en comparación a una red MPLS tradicional, generando una topología que evidencie el impacto sobre los servicios diferenciados.Con el aumento de nuevos dispositivos y aplicaciones, la última década ha sido testigo de un crecimiento exponencial del volumen de tráfico en las redes de comunicación (Experimen, 2017), por otra parte, dadas las situaciones de pandemia del COVID19, el uso de servicios de streaming, VoIP y WEB (Bahnasse et al., 2018) demanda de grandes recursos donde la calidad de servicio (QoS) se vuelve un tema muy crítico. Según (Servicio, 2016) la QoS se define como un conjunto de tecnologías que permiten a los administradores de red manejar los efectos de la congestión del tráfico usando óptimamente los diferentes recursos de la red, en lugar de ir aumentando continuamente capacidad, sino distribuirlo de acuerdo a las necesidades de la empresa. La gran mayoría de empresas en el Ecuador utilizan redes con el protocolo MPLS (Sonny Eli Zaluchu, 2021), pero tal y como lo menciona en su caso de estudio muchos de los routers con los que se operan ya han cumplido su vida útil o se encuentran obsoletos, también uno de los problemas que se llegan a presentar es el limitado crecimiento de capacidades de transporte dando como resultado que este tipo de redes ya no pueden soportan la demanda del tráfico actual. Dada su infraestructura y administración cerrada las redes MPLS no permiten los cambios dinámicos (Bahnasse et al., 2018) ocasionando que no se puedan alinear a las necesidades de negocio por su retardo en el despliegue, mala gestión de los recursos e interrupciones en su servicio (Sinha et al., 2017). El paradigma denominado SDN junto con el protocolo OpenFlow proporciona muchas funciones nuevas para gestión del tráfico (Xie et al., 2019), entre muchos de los beneficios que proporciona OpenFlow está su capacidad de enrutar y redireccionar el tráfico según el patrón de la red, por lo tanto nos abre un área muy amplia para la investigación sobre ingeniería de tráfico (Wiley, 2020), pero no todo lo que puede aportar SDN se encuentra en OpenFlow, sino que al permitirnos separar el plano de control del plano de datos nos permite mayor flexibilidad para la expansión de las redes. En este sentido, uno de los puntos importantes de las redes SDN se encuentra en plano de control, al cual se le puede definir como el cerebro de la arquitectura (Wu et al., 2020), esta es la plataforma de código abierto para SDN OpenDayLight, la cual se encarga de proporcionar el control programático centralizado, así como la supervisión de los dispositivos de red (Badotra & Singh, 2017) y su compatibilidad con OpenFlow , implementando funcionalidades como el descubrimiento de la topología, descubrimiento de rutas diseñadas, asignación de recursos de manera eficiente, entre otras. Por otra parte, la arquitectura horizontal que nos brinda las redes SDN fomenta la interoperabilidad y potencia la innovación, permitiendo que tan pronto la red comience a operar el controlador que tiene una vista general de la topología y una mejor capacidad de programación es capaz de superar las formas de descubrimiento de rutas de MPLS (Vissicchio et al., 2014). Con esto es muy claro que si se realiza una red híbrida SDN/MPLS utilizando las ventajas que nos llegan a ofrecer como; la reutilización de infraestructura MPLS existente, menor cantidad de interrupciones en los servicios, mejor asignación de los recursos y reducción de costes en equipos. En Ecuador la investigación en esta área es prácticamente una incógnita (Sinha et al., 2017), tomando en cuenta de que según las últimas estadísticas únicamente la transmisión de video por IP ocupa el 82% del tráfico IP total (Servicio, 2016), si a esto le sumamos el tráfico que se genera con VoIP y WEB sin duda alguna que el escenario establecido a analizar es muy prometedor.Ingenierí

Software-Defined Networking: A Comprehensive Survey

peer reviewedThe Internet has led to the creation of a digital society, where (almost) everything is connected and is accessible from anywhere. However, despite their widespread adoption, traditional IP networks are complex and very hard to manage. It is both difficult to configure the network according to predefined policies, and to reconfigure it to respond to faults, load, and changes. To make matters even more difficult, current networks are also vertically integrated: the control and data planes are bundled together. Software-defined networking (SDN) is an emerging paradigm that promises to change this state of affairs, by breaking vertical integration, separating the network's control logic from the underlying routers and switches, promoting (logical) centralization of network control, and introducing the ability to program the network. The separation of concerns, introduced between the definition of network policies, their implementation in switching hardware, and the forwarding of traffic, is key to the desired flexibility: by breaking the network control problem into tractable pieces, SDN makes it easier to create and introduce new abstractions in networking, simplifying network management and facilitating network evolution. In this paper, we present a comprehensive survey on SDN. We start by introducing the motivation for SDN, explain its main concepts and how it differs from traditional networking, its roots, and the standardization activities regarding this novel paradigm. Next, we present the key building blocks of an SDN infrastructure using a bottom-up, layered approach. We provide an in-depth analysis of the hardware infrastructure, southbound and northbound application programming interfaces (APIs), network virtualization layers, network operating systems (SDN controllers), network programming languages, and network applications. We also look at cross-layer problems such as debugging and troubleshooting. In an effort to anticipate the future evolution of this - ew paradigm, we discuss the main ongoing research efforts and challenges of SDN. In particular, we address the design of switches and control platforms—with a focus on aspects such as resiliency, scalability, performance, security, and dependability—as well as new opportunities for carrier transport networks and cloud providers. Last but not least, we analyze the position of SDN as a key enabler of a software-defined environment

Pemerataan Beban Jaringan Menggunakan Metode Hybrid (Proactive Dan Reactive) Pada Jaringan Sdn (Software Defined Networking)

Mendistribusikan trafik pada topologi jaringan fat-tree yang sering digunakan di jaringan data center sangatlah penting. Multipath routing adalah teknik umum yang digunakan untuk menyeimbangkan trafik. Dalam Software Defined Networking (SDN), jalur routing sepenuhnya dikendalikan oleh controller untuk memilih jalur optimal atau beberapa jalur untuk meningkatkan throughput trafic-flow dan menurunkan latensi pengiriman data. Beberapa metode telah dilakukan pada penelitian sebelumnya diantaranya Slavica dengan mode controller proactive dan segmentasi traffic-flow dengan mempertimbangkan pemisahan antara TCP dan UDP. Selain itu LABERIO juga telah melakukan pemerataan traffic-flow dengan menggunakan mode controller reactive dan segmentasi traffic-flow dengan mempertimbangkan IP tujuan. Kemudian metode LABERIO disempurnakan dengan metode DLPO dengan tidak melakukan perubahan jalur dan menggantinya dengan merubah nilai priority pada flow-table untuk mengoptimalkan traffic-flow UDP. Akan tetapi ketika terdapat traffic-flow UDP dengan beberapa traffic-flow TCP dengan IP tujuan yang sama, pada metode yang digunakan pada penelitian sebelumnya tidak dapat mengakomodasi keadaan tersebut sehingga menyebabkan traffic-flow tidak merata ke seluruh path yang tersedia. Penelitian ini mengimplementasikan mode hibridisasi controller proactive-reactive pada SDN untuk menyeimbangkan trafik. SDN Controller memonitor utilisasi jalur dan secara reaktif akan menginstal flow-tables ke switch yang sesuai setiap kali ada lonjakan trafik yang signifikan untuk periode tertentu. SDN Controller akan secara proaktif menerapkan flow-table ke switch yang sesuai. Metode Hybrid melakukan segmentasi traffic-flow dengan mempertimbangkan seluruh elemen flow (IP sumber dan tujuan, internet protocol number dan port number sumber dan tujuan). Dengan melakukan beberapa pengujian, diantaranya adalah dengan memberikan beberapa traffic-flow TCP dan UDP secara bersamaan, hasil evaluasi pada topologi fat-treemenunjukkan bahwa bahwa mode hibridisasi yang diusulkan berkinerja lebih baik daripada LABERIO dengan throughput traffic-flow rata – rata sebesar 7,558 Mbps (25,193%) dari Slavica, 2,38 Mbps (7,93%) dari LABERIO dan 3,44 Mbps (11,47%) dari DLPO. Pengujian latensi pengiriman data juga dilakukan dengan memberikan proses copy file dan mendapatkan hasil untuk latensi pengiriman data, metode dapat menurunkan rata – rata sebesar 31 detik dari Slavica, 18 detik dari LABERIO dan 21 detik dari DLPO. Pada kondisi dimana terjadi traffic-spike, metode Hybrid dapat mengakomodasi dengan memberikan time-threshold sebesar 15 detik sehingga tidak melukan perhitungan ulan

Long-Wave Infrared Digital Holography

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