TOWARDS A NEW SDN NFV APPROACH
FOR THE MANAGEMENT OF MPLS
INFRASTRUCTURES
Faycal Bensalah
Ph.D Student, Network and Telecommunications team.
Faculty of Sciences, Chouaib Doukkali University.
El Jadida (Morocco).
E-mail: f.bensalah@ucd.ac.ma
Najib El Kamoun
Ph.D, professor in the dept. of physics.
Researcher member on STIC laboratory,
header of Network and Telecommunications team.
Faculty of Sciences, Chouaib Doukkali University.
El Jadida (Morocco).
E-mail: elkamoun@ucd.ac.ma
Recepción: 29/07/2019 Aceptación: 19/09/2019 Publicación: 06/11/2019
Citación sugerida:
Bensalah, F. y El Kamoun, N. (2019). Towards a new SDN NFV approach for the
management of MPLS infrastructures. 3C Tecnología. Glosas de innovación aplicadas a la pyme.
Edición Especial, Noviembre 2019, 107-119. doi: http://dx.doi.org/10.17993/3ctecno.2019.
specialissue3.107-119
Suggested citation:
Bensalah, F. & El Kamoun, N. (2019). Towards a new SDN NFV approach for the
management of MPLS infrastructures. 3C Tecnología. Glosas de innovación aplicadas a la pyme.
Speciaal Issue, November 2019, 107-119. doi: http://dx.doi.org/10.17993/3ctecno.2019.
specialissue3.107-119
108
109
3C Tecnología. Glosas de innovación aplicadas a la pyme. ISSN: 2254–4143
ABSTRACT
Network infrastructure virtualization has become an active research area. Indeed,
network feature virtualization (NFV) brings unparalleled exibility to next-
generation networks and goes far beyond cost reduction. This technology reduces
vendor dependency and allows new features to be deployed faster than ever before.
In this article we propose a new solution for the virtualization of network services,
particularly in relation to concepts related to MPLS technology. Our solution ensures
fast access to the access network while guaranteeing quality of service.
KEYWORDS
NFV, SDN, MPLS, Automation.
108
109
Edición Especial Special Issue Noviembre 2019
DOI: http://dx.doi.org/10.17993/3ctecno.2019.specialissue3.107-119
1. INTRODUCTION
NFV (virtualization of network functions) is a way to reduce costs and accelerate
service deployment for network operators by dissociating functions such as rewalls
or encryption from any dedicated hardware and moving them to virtual servers
(Hawilo, Shami, Mirahmadi, & Asal, 2014). The NFV concept for virtualization of
network functions is like a new step towards creating a more agile and cost-eective
network infrastructure. Network function virtualization (NFV) extracts network
functions, allowing software components running on standardized compute nodes
to install, control and manipulate them. NFV integrates cloud and virtualization
technologies to quickly develop new network services while optimizing exibility
in terms of scalability and automation. These technologies are often combined in
NFV and SDN solutions. This virtualization of network functions reduces network
operators’ dependence on dedicated hardware and improves scalability and
customization across the entire network. Unlike a virtual network, the NFV only
seeks to ooad certain network functions rather than the entire network.
The NFV reduces the need for dedicated hardware to deploy and manage networks
by transferring network functions to software that runs on standard hardware and
can be managed from anywhere on the operator’s network.
The separation of network functions from hardware provides many advantages for
the network operator, including:
• Reduction of the space required for the network’s physical equipment.
• Reduction of grid power consumption.
• Reduction of network maintenance costs.
• Simplication of network upgrades.
• Extension of the life cycle of network physical equipment.
• Reduced maintenance and material costs.
110
111
3C Tecnología. Glosas de innovación aplicadas a la pyme. ISSN: 2254–4143
The desire to automate the orchestration and management of the network, storage
and computing resources is a key factor in NFV and SDN development. Imagine
a scenario involving a physical server with 10 virtual machines or hundreds of
containers. This concept cannot be evolutionary if it involves manual operations.
Automation enables virtualized network functions (VNFs) such as virtual machines
(VMs), containers, routers, rewalls and intrusion prevention systems (IPSs) to be
quickly created or removed to automatically adapt them to dynamic demand.
SDN and NFV are not an integral part of each other (Bahnasse, Louhab, Oulahyane,
Talea, & Bakali, 2018). While the two concepts are quite dierent, they are nevertheless
related. The NFV can thus be implemented without the need for an SDN, although
these two approaches can be combined to provide greater added value.
The objectives of the NFV can be achieved by using non-SDN mechanisms,
using techniques currently used in many datacenters. But approaches based on
the separation of control and data transfer plans, as proposed by the SDN, can
improve performance, simplify compatibility with existing deployments and facilitate
operation and maintenance procedures.
The NFV can support the SDN by providing the infrastructure on which the SDN
software can be run. In addition, the NFV is closely aligned with the SDN’s objectives
for the use of servers and switches.
2. STATE OF THE ART
The SDN and NFV technologies propose to revolutionize the way networks operate,
and the success of these two technologies may well depend on their ability to interact
harmoniously, if not support each other. To this end, and according to Ding, Qi,
Wang, and Chen (2015), the SDN can provide connectivity between NFV les in a
exible and automated manner, thus simplifying network management. In addition,
NFV can use the SDN as part of a service function chain (SFC). In this case, SDN
controllers and business applications can run as NFV les in a scalable environment
and benet from essential features such as availability, reliability and elasticity.
110
111
Edición Especial Special Issue Noviembre 2019
DOI: http://dx.doi.org/10.17993/3ctecno.2019.specialissue3.107-119
Several studies focus on the integration of NFV and SDN in dierent environments
such as cloud computing, intelligent wide area networks, customer premises
equipment, 5G, telemedicine, etc. These studies address several challenges, such
as reliability, performance and scalability. These studies use a distinct architectural
design logic as well as functional and non-functional requirements (Basta, Kellerer,
Homann, Morper, & Homann, 2014; Ordonez-Lucena, Ameigeiras, Lopez,
Ramos-Munoz, Lorca, & Folgueira, 2017; Vilalta et al., 2016).
Ensuring a good QoS level for multi-path networks is one of the major challenges,
both for wireline networks (Wu, Cheng, Yuen, Cheung, & Chen, 2015; Wu, Yuen,
Cheng, Shang, & Chen, 2014) and wireless networks more precisely those with
energy consumption constraints (Wu, Cheng, Wang, & Chen, 2018; Wu, Yuen,
Cheng, Wang, & Chen, 2016). The undesirable eects of multi-path and service
degradation can only be truly felt when multimedia or real-time applications are
routed through the network, more precisely and especially in wireless networks
where bandwidth is one of the major concerns. Despite the many CMT (Concurrent
Multipath Transfer) solutions, they remain limited due to the asymmetry of link
performance and especially the sensitivity of some applications to SLA constraints.
Wu, Yuen, Wang and Chen (2015) in their work considered as an improvement
of CMT solutions considering video distortion in the path selection process, the
proposed solution is published as Distortion Aware CMT (CMT-DA). The latter
consists of rst estimating the available bandwidth per path using Round Trip Time
(RTT), congestion window and Timeout retransmission (RTO). Then, perform a
ow rate allocation, i. e. send the acknowledgement packets via the most ecient
uplinks in order to be able to adapt the congestion window. CMT-DA has been
tested in a variety of heterogeneous wireless networks: WiFi, WiMax and cellular, the
results obtained in terms of PSNR (Peak Signal to Noise Ratio), Goodput and Inter-
Packet delay have shown the radical improvement in the QoS of multimedia trac
compared to existing wireless heterogeneous network solutions.
112
113
3C Tecnología. Glosas de innovación aplicadas a la pyme. ISSN: 2254–4143
3. PROPOSED APPROACH
Our approach is based on three logical layers; the service layer, the orchestration
layer, and the physical layer. Figure 1 illustrates the architecture of the proposed
approach.
Figure 1. The proposed NFV architecture for virtualizing quality of service in an MPLS infrastructure.
The service layer provides all applications and services that aect the process of
routing and routing MPLS frames (Bahnasse, Louhab, Oulahyane, Talea, & Bakali,
2018). This layer provides all the graphical interfaces through which the infrastructure
administrator can specify the applications to be used, their characteristics, and their
QoS constraints. Figure 2 illustrates an example of the service layer interface.
112
113
Edición Especial Special Issue Noviembre 2019
DOI: http://dx.doi.org/10.17993/3ctecno.2019.specialissue3.107-119
Figure 2. Service layer interface.
The software layer provides the necessary mechanisms for detecting user activity,
including:
• The destination IP address;
• The state of the best way to this destination;
• The other possible paths for this destination;
• The user’s subscription type;
• The bandwidth requested by the user;
• The user’s permanent activity;
This layer is based on active metrology protocols (SNMP, CMIP) to ensure these
objectives mentioned above.
The software layer also allows intelligent management of the paths that a user must
take for a better quality of service. This path determination process is based on the
RSVP protocol for the a priori establishment of the path. A list of paths is then
114
115
3C Tecnología. Glosas de innovación aplicadas a la pyme. ISSN: 2254–4143
dened in a stack sorted in terms of available bandwidth, the operating steps are as
follows:
1. Calculate all paths between a source and a destination and store them in a
stack.
2. Sort these paths according to the available bandwidth of each link.
3. Stack the results according to the number of links.
4. If the available bandwidth is enough to transmit user trac, trac is routed
by the rst path.
5. Otherwise, the priority of active trac is checked. If it exceeds that of the
generated trac, then the trac is routed by the following path.
To address the path with QoS constraints and the shortest path, we assume that the
graph G=[X,U] represents a network of an N router and M links. Au, represents the
available bandwidth of a link for each u U.
for each request to establish an LSP (K), dened by a source S(k), a destination R(k),
the requested bandwidth dk and the nth path between s(k) and R(k) for all n [1, P(k)].
The links responding to bandwidth constraints are dened by:
Min {}, u [1, M]
It is essential to detect a user’s activity, and it is according to this activity that the
routing process and QoS will be executed, to achieve this objective our model is
based on the NBAR and Netow protocols. Our model is based on ow sampling
methods:
• Full: generates for each network ow an information that will be exported.
This method is the oldest and the one supported on almost all routers but is no
longer very common among operators because the router load and the amount
of accounting information generated, especially during a shared denial of
service, are too high. On the other hand, in the context of an internal network,
114
115
Edición Especial Special Issue Noviembre 2019
DOI: http://dx.doi.org/10.17993/3ctecno.2019.specialissue3.107-119
it is almost mandatory if we want to be able to detect slow recognitions or
violations of policies that try to be discreet.
• Sampled: Allows you to dene the percentage of ows to be exported over the
total number of ows generated. In general, operators are limited to 1 per 100
or even 1 per 1000. Even at 1 per 1000, a shared denial of service remains
relatively easy to detect. The advantage of this method is the reduction of the
router’s CPU load and the amount of Netow exported. The disadvantage is
that it is not statistically good (deterministic function).
• Random Sampled: has been introduced relatively recently and on platforms of
the 72xx/75xx type (whereas sampled was only available on GSR and 76xx,
i.e. routers that support distributed CEF). The dierence between sampled
and random sampled is that the latter selects a random datagram from the
congured <x> which is statistically better.
Indeed, thanks to the monitoring of the user’s activity, our model can detect the
user’s need in terms of bandwidth according to the type of application.
The Hardware layer allows several VRFs to be instantiated within the same gateway in
accordance with user-specic routing policies. It allows to dene within the gateways
the dierent QoS classes and policies adapted for a user within a well determined
architecture (MPLS, MPLS VPN, or traditional IP).
As soon as policies are congured, our platform establishes sockets with the dierent
gateways of the network using the Python language. These sockets are used to connect
to the gateways and execute information gathering and conguration commands,
Figure 3 illustrates an example of the sockets used.
116
117
3C Tecnología. Glosas de innovación aplicadas a la pyme. ISSN: 2254–4143
Figure 3. Python socket for connection with Cisco routers.
4. CONCLUSIONS
In this paper we have proposed a new architecture for virtualization of MPLS
infrastructures by combining SDN and NFV approaches. The proposed architecture
manages network services and equipment to meet subscriber QoS requirements.
The adoption of such an architecture can provide unparalleled exibility and cost
reduction, as a single gateway can instantiate multiple virtual routing tables, each of
which is subject to a routing policy that meets users’ QoS requirements.
REFERENCES
Bahnasse, A., Louhab, F. E., Oulahyane, H. A., Talea, M., & Bakali, A.
(2018). Novel SDN architecture for smart MPLS trac engineering-DiServ
aware management. Future Generation Computer Systems, 87, 115-126. doi: https://
doi.org/10.1016/j.future.2018.04.066
116
117
Edición Especial Special Issue Noviembre 2019
DOI: http://dx.doi.org/10.17993/3ctecno.2019.specialissue3.107-119
Bahnasse, A., Louhab, F. E., Oulahyane, H. A., Talea, M., & Bakali, A.
(2018). Smart bandwidth allocation for next generation networks adopting
software-dened network approach. Data in brief, 20, 840-845. doi: https://doi.
org/10.1016/j.dib.2018.08.091
Basta, A., Kellerer, W., Homann, M., Morper, H. J., & Homann, K.
(2014, August). Applying NFV and SDN to LTE mobile core gateways, the
functions placement problem. In Proceedings of the 4th workshop on All things
cellular: operations, applications, & challenges, 33-38. ACM. doi: https://doi.
org/10.1145/2627585.2627592
Ding, W., Qi, W., Wang, J., & Chen, B. (2015). OpenSCaaS: an open service chain
as a service platform toward the integration of SDN and NFV. IEEE Network,
29(3), 30-35. doi: https://doi.org/10.1109/MNET.2015.7113222
Hawilo, H., Shami, A., Mirahmadi, M., & Asal, R. (2014). NFV: State of the art,
challenges and implementation in next generation mobile networks (vEPC). arXiv preprint
arXiv:1409.4149
Ordonez-Lucena, J., Ameigeiras, P., Lopez, D., Ramos-Munoz, J. J., Lorca,
J., & Folgueira, J. (2017). Network slicing for 5G with SDN/NFV: Concepts,
architectures, and challenges. IEEE Communications Magazine, 55(5), 80-87. doi:
https://doi.org/10.1109/MCOM.2017.1600935
Vilalta, R., Mayoral, A., Pubill, D., Casellas, R., Martínez, R., Serra, J., ...
Muñoz, R. (2016, March). End-to-end SDN orchestration of IoT services using
an SDN/NFV-enabled edge node. In 2016 Optical Fiber Communications Conference
and Exhibition (OFC), 1-3. IEEE. doi: https://doi.org/10.1364/OFC.2016.
W2A.42
Wu, J., Cheng, B., Wang, M., & Chen, J. (2018). Energy-aware concurrent
multipath transfer for real-time video streaming over heterogeneous wireless
networks. IEEE Transactions on Circuits and Systems for Video Technology, 28(8), 2007-
2023. doi: https://doi.org/10.1109/tcsvt.2017.2695368
118
119
3C Tecnología. Glosas de innovación aplicadas a la pyme. ISSN: 2254–4143
Wu, J., Cheng, B., Yuen, C., Cheung, N. M., & Chen, J. (2015). Trading
delay for distortion in one-way video communication over the internet. IEEE
Transactions on Circuits and Systems for Video Technology, 26(4), 711-723. doi: https://
doi.org/10.1109/tcsvt.2015.2412774
Wu, J., Yuen, C., Cheng, B., Shang, Y., & Chen, J. (2014). Goodput-aware load
distribution for real-time trac over multipath networks. IEEE Transactions on
Parallel and Distributed Systems, 26(8), 2286-2299. doi: https://doi.org/10.1109/
TPDS.2014.2347031
Wu, J., Yuen, C., Cheng, B., Wang, M., & Chen, J. (2016). Energy-minimized
multipath video transport to mobile devices in heterogeneous wireless networks.
IEEE Journal on Selected Areas in Communications, 34(5), 1160-1178. doi: https://doi.
org/10.1109/JSAC.2016.2551483
Wu, J., Yuen, C., Wang, M., & Chen, J. (2015). Content-aware concurrent
multipath transfer for high-denition video streaming over heterogeneous wireless
networks. IEEE Transactions on Parallel and Distributed Systems, 27(3), 710-723. doi:
https://doi.org/10.1109/TPDS.2015.2416736
