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  • 1.
    Rathore, M. Siraj
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster (Stängd 20120101), Telekommunikationssystem, TSLab (stängd 2012-01-01).
    Hidell, Markus
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster (Stängd 20120101), Telekommunikationssystem, TSLab (stängd 2012-01-01).
    Sjödin, Peter
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster (Stängd 20120101), Telekommunikationssystem, TSLab (stängd 2012-01-01).
    Performance Evaluation of Open Virtual Routers2010Inngår i: 2010 IEEE GLOBECOM WORKSHOPS, IEEE , 2010, s. 288-293Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A major challenge in network virtualization is to virtualize the components constituting the network, in particular the routers. In the work presented here, we focus on how to use open source Linux software in combination with commodity hardware to build open virtual routers. A general approach in open router virtualization is to run multiple virtual operating systems in parallel on the same PC hardware. This means that overhead in terms of additional packet processing is introduced along the data path through the router. In this paper, we investigate these performance penalties and suggest how best to combine software modules to form an open virtual router.

  • 2.
    Rathore, M. Siraj
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Hidell, Markus
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Sjödin, Peter
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Towards Performance Guarantees for Virtualized Network Functions2017Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The trend of consolidating network functions from specialized hardware to software running on virtualization servers brings significant advantages for reducing costs and simplifying service deployment.  However, virtualization techniques have significant limitations when it comes to networking as there is no support for guaranteeing that network functions meet their service requirements. In this paper, we present a design for providing service guarantees to virtualized network functions based on rate control. The design is a combination of rate regulation through token bucket filters and the regular scheduling mechanisms in operating systems.  It has the attractive property that traffic profiles are maintained throughout a series of network functions, which makes it well suited for service function chaining.

    We discuss implementation alternatives for the design, and demonstrated how it can be implemented on two virtualization platforms: LXC containers and with the KVM hypervisor. To evaluate the design, we conduct experiments where we measure throughput and latency using IP forwarders as virtual network functions. Two significant factors for performance are investigated: the design of token buckets and the packet clustering effect that comes from scheduling. We implement a token bucket filter at the network device level, which is found to give better performance than the regular token bucket in Linux traffic control. The clustering effect adds burstiness, which in turn increases latency and limits the traffic profiles that can be supported. The effect is significant with KVM, but not with LXC. Finally, we demonstrate how performance guarantees are achieved for multiple virtual routers under different scenarios.

  • 3.
    Rathore, Muhammad Siraj
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Performance, Isolation and Service Guarantees in Virtualized Network Functions2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    A network is generally a collection of different hardware-based network devices carrying out various network functions, (NF). These NF implementations are special purpose and expensive. Network function virtualization (NFV) is an alternative which uses software-based implementation of NFs in inexpensive commodity servers. However, it is challenging to achieve high networking performance due to bottlenecks in software, particularly in a virtualized environment where NFs are implemented inside the virtual machines (VM). The performance isolation is yet another challenge, which means that the load on one VM should not affect the performance of other VMs. However, it is difficult to provide performance isolation due to resource contention in a commodity server. Furthermore, different NFs may require different service guarantees which are difficult to ensure due to the non-deterministic performance behavior of a commodity server.

    In this thesis we investigate how the challenges of performance, isolation and service guarantees can be addressed for virtual routers (VR), as an example of a virtualized NF. It is argued that the forwarding path of a VR can be modified in an efficient manner in order to improve the forwarding performance. When it comes to performance isolation, poor isolation is observed due to shared network queues and CPU sharing among VRs. We propose a design with SR-IOV, which allows reserving a network queue and CPU core for each VR. As a result, the resource contention is reduced and strong performance isolation is achieved. Finally, it is investigated how average throughput and bounded packet delay can be guaranteed to VRs. We argue that a classic rate-controlled service discipline can be adapted in a virtual environment to achieve service guarantees. We demonstrate that firm service guarantees can be achieved with little overhead of adding token bucket regulator in the forwarding path of a VR.

  • 4.
    Rathore, Muhammad Siraj
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster, Telekommunikationssystem, TSLab.
    Hidell, Markus
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster, Telekommunikationssystem, TSLab.
    Peter, Sjödin
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster, Telekommunikationssystem, TSLab.
    Data Plane Optimizations in Open Virtual Routers2011Inngår i: IFIP Networking 2011, Springer Verlag, Heidelberg , 2011, s. 379-392Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A major challenge in network virtualization is to virtualize the components constituting the network, in particular the routers. In the work presented here, we focus on how to use open source Linux software in combination with commodity hardware to build open virtual routers. A general approach in open router virtualization is to run multiple virtual instances in parallel on the same PC hardware. This means that virtual components are combined in the router’s data plane, which can result in performance penalty. In this paper, we investigate the impact of the design of virtual network devices on router performance in Linux namespace environment. We identify performance bottlenecks along the packet data path. We suggest design changes to improve performance. In particular, we investigate modifications of the ―macvlan‖ device, and analyze the performance improvements in terms of packet forwarding. We also investigate how the number of virtual routers and virtual devices within a physical machine influence performance.

  • 5.
    Rathore, Muhammad Siraj
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Hidell, Markus
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Sjödin, Peter
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    KVM vs. LXC: Comparing Performance and Isolation of Hardware-assisted Virtual Routers2013Inngår i: American Journal of Networks and Communications, ISSN 2326-893X, Vol. 2, nr 4, s. 88-96Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Concerns have been raised about the performance of PC-based virtual routers as they do packet processing in software. Furthermore, it becomes challenging to maintain isolation among virtual routers due to resource contention in a shared environment. Hardware vendors recognize this issue and PC hardware with virtualization support (SR-IOV and Intel-VTd) has been introduced in recent years. In this paper, we investigate how such hardware features can be integrated with two different virtualization technologies (LXC and KVM) to enhance performance and isolation of virtual routers on shared environments. We compare LXC and KVM and our results indicate that KVM in combination with hardware support can provide better trade-offs between performance and isolation. We notice that KVM has slightly lower throughput, but has superior isolation properties by providing more explicit control of CPU resources. We demonstrate that KVM allows defining a CPU share for a virtual router, something that is difficult to achieve in LXC, where packet forwarding is done in a kernel shared by all virtual routers.

  • 6.
    Rathore, Muhammad Siraj
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster, Telekommunikationssystem, TSLab.
    Razzaq, Adil
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster, Telekommunikationssystem, TSLab.
    Hidell, Markus
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster, Telekommunikationssystem, TSLab.
    Sjödin, Peter
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster, Telekommunikationssystem, TSLab.
    Site-to-Site VPN Technologies: A Survey2009Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Virtual Private Network (VPN) is a popular way to build private networks using shared network infrastructure. A variety of VPN technologies exist today operating on different layers of OSI model. This paper presents a detailed survey and provides a classification of various types of VPNs. Layer 1 VPN is also included which is an emerging technology. Services offered by each VPN with implementation methods are described. Protocols, tunneling mechanisms and hardware components used for the deployment are also explored.

  • 7.
    Rathore, Siraj
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Hidell, Markus
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Sjödin, Peter
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    PC-based Router Virtualization with Hardware Support2012Inngår i: Proceedings - International Conference on Advanced Information Networking and Applications, AINA, IEEE Computer Society, 2012, s. 573-580Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper we focus on how to use open source Linux software in combination with PC hardware to build high speed virtual routers. Router virtualization means that multiple virtual router instances will run in parallel on the same hardware. To enable this, virtual components are combined in the router's data plane. This can result in performance penalties. Furthermore, an overloaded virtual router can affect the performance of other virtual routers running in parallel. Achieving high performance and strong performance isolation in a virtualized environment is challenging. We investigate how hardware can help to achieve these goals in the Linux Namespaces environment. We propose a forwarding architecture for virtual routers based on multi-core hardware where virtual routers can run in parallel on different CPU cores. This reduces resource contention among virtual routers and results in improved performance and isolation. To enable this architecture, we find that hardware based I/O virtualization support is essential. We demonstrate this by making a comparison with a software based I/O virtualization approach. We also show that hardware assisted virtual routers can achieve better aggregate throughput than a non-virtualized router on a multi-core platform.

  • 8.
    Razzaq, Adil
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster, Telekommunikationssystem, TSLab.
    Siraj Rathore, Muhammad
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster, Telekommunikationssystem, TSLab.
    An approach towards resource efficient virtual network embedding2010Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Network virtualization is at the heart of efforts to end Internet ossification, and utilize network infrastructure efficiently. The key concept is to share the infrastructure resources among many users at the same time and in such a way to enable them to deploy the required architectures. This leads to virtual networks (VNs), demanding different resources that have to be embedded on the underlying shared infrastructure network. The requirements of a VN can be based on factors such as, the type of traffic it needs to carry. Some portion of the same resources (substrate resources) needs to be assigned to every VN and the substrate resources are also finite. Thus, a mechanism needs to be devised in order to schedule the resources. This embedding process with resource constraints on virtual nodes and links to be applied on the substrate, which also has limited resources, is challenging and corresponds to the category of NP-hard problems. In this paper, we propose an approach to solve this problem by mapping the vertices of the VN as closely as possible in the substrate network and then assigning virtual edges to the shortest paths which satisfy their demands. This could enable the substrate to accommodate more VNs in the same resource database and hence optimize the substrate's bandwidth utilization. To the best of our knowledge closest node mapping proposed in this solution is a novel approach and is evaluated and compared to the existing approach of greedy node mapping in different scenarios. The sensitivity analysis by varying the different parameters and their effect on mapping VNs is also presented.

  • 9.
    Tanyingyong, Voravit
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Rathore, M. Siraj
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Hidell, Markus
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Sjödin, Peter
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Carenet: An Architecture for Home-based Healthcare Services2013Inngår i: SNCNW 2013, 2013, s. 28-31Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Doctor shortage is a universal problem. Technologies can be used to address the issue by extending the healthcare services over the data network to virtually anywhere. In this paper, we propose Carenet architecture to extend healthcare services to the home of a patient in a robust, secure, and cost-effective manner. The prototype architecture is developed using a residential gateway (RG). The RG is built using open source software on Commodity-Off-The-Shelf (COTS) hardware. It uses low-power components with multiple power sources to provide robustness. The healthcare services are offered over a private overlay network. Linux containers are used to provide service isolation on the RG. The data is encrypted at the application level for each service to ensure confidentiality. Resilient communication is realized based on physical redundant links from two Internet connections from different ISPs. The failover time within sub-seconds time frame is achieved using our prototype RG.

  • 10.
    Tanyingyong, Voravit
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Rathore, M. Siraj
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Hidell, Markus
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Sjödin, Peter
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Resilient Communication through Multihoming for Remote Healthcare Applications2013Inngår i: 2013 IEEE Global Communications Conference (GLOBECOM), IEEE , 2013, s. 1335-1341Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Advancements in today's technologies make it possible to offer competitive home-based healthcare services using software routers based on open source software combined with Commodity-Off-The-Shelf (COTS) hardware. In this paper, we propose resilient communication through multihoming for remote healthcare applications. The solution is based on Bidirectional Forwarding Detection (BFD) for fast failure detection and a customized rerouting operation. We investigate the tradeoff between short reaction times for rerouting and low probability of false alarms. This is challenging to achieve under high traffic loads since the load affects the BFD session which is formed to monitor the bidirectional forwarding capabilities. We propose a simple mechanism that provides fast failover and meanwhile maintains a very low probability of generating false alarms and unwanted rerouting decisions. The mechanism is based on allocation of system resources for processing BFD control messages, and we demonstrate through empirical results that BFD then can be used in software routers to provide average failover times within 200 ms.

  • 11.
    Tanyingyong, Voravit
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Rathore, M. Siraj
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Hidell, Markus
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Sjödin, Peter
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Pehrson, Björn
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Jonsson, Sven
    Karolinska University Hospital.
    Groth, Kristina
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Carenet: An Infrastructure for Home-Based Healthcare Services2013Inngår i: Medicinteknikdagarna 2013, 2013Konferansepaper (Fagfellevurdert)
1 - 11 of 11
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  • en-GB
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