Name: automated deployment of an internet protocol telephony service on unmanned aerial vehicles using network functions virtualization
Uploaded: 2019-11-26T14:00:00
Duration: 7 min 49 s
Description: Watch this Scientific Journal Video about Automated Deployment of an Internet Protocol Telephony Service on Unmanned Aerial Vehicles Using Network Functions Virtualization at JoVE.com

This work was partially supported by the European H2020 5GRANGE project (grant agreement 777137), and by the 5GCIty project (TEC2016-76795-C6-3-R) funded by the Spanish Ministry of Economy and Competitiveness. The work of Luis F. Gonzalez was partially supported by the European H2020 5GinFIRE project (grant agreement 732497).

<ol>
	<li>Sanchez-Aguero, V., Nogales, B., Valera, F., Vidal, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigating+the+deployability+of+VoIP+services+over+wireless+interconnected+Micro+Aerial+Vehicles.">Investigating the deployability of VoIP services over wireless interconnected Micro Aerial Vehicles.</a> Internet Technology Letters. 1 (5), 40 (2018).</li><li>Maxim, V., Zidek, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+of+high-performance+multimedia+control+system+for+UAV/UGV+based+on+SoC/FPGA+Core.">Design of high-performance multimedia control system for UAV/UGV based on SoC/FPGA Core.</a> Procedia Engineering. 48, 402-408 (2012).</li><li>Vidal, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enabling+Multi-Mission+Interoperable+UAS+Using+Data-Centric+Communications.">Enabling Multi-Mission Interoperable UAS Using Data-Centric Communications.</a> Sensors. 18 (10), 3421 (2018).</li><li>Vidal, I., Valera, F., D&#237;az, M. A., Bagnulo, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+practical+deployment+of+a+network-centric+remotely+piloted+aircraft+system.">Design and practical deployment of a network-centric remotely piloted aircraft system.</a> IEEE Communications Magazine. 52 (10), 22-29 (2014).</li><li>Jin, Y., Minai, A. A., Polycarpou, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cooperative+real-time+search+and+task+allocation+in+UAV+teams.">Cooperative real-time search and task allocation in UAV teams.</a> 42nd IEEE International Conference on Decision and Control. 1, 7-12 (2003).</li><li>Maza, I., Ollero, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiple+UAV+cooperative+searching+operation+using+polygon+area+decomposition+and+efficient+coverage+algorithms.">Multiple UAV cooperative searching operation using polygon area decomposition and efficient coverage algorithms.</a> Distributed Autonomous Robotic Systems. 6, 221-230 (2007).</li><li>Quaritsch, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Collaborative+microdrones:+applications+and+research+challenges.">Collaborative microdrones: applications and research challenges.</a> Proceedings of the 2nd International Conference on Autonomic Computing and Communication Systems. , 38 (2008).</li><li>Waharte, S., Trigoni, N., Julier, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coordinated+search+with+a+swarm+of+UAVs.">Coordinated search with a swarm of UAVs.</a> 2009 6th IEEE Annual Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks Workshops. , 1-3 (2009).</li><li>De Freitas, E. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=UAV+relay+network+to+support+WSN+connectivity.">UAV relay network to support WSN connectivity.</a> International Congress on Ultra-Modern Telecommunications and Control Systems. , 309-314 (2010).</li><li>European Telecommunications Standards Institute. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Network+Functions+Virtualisation+(NFV);+Architectural+Framework;+Research+Report+ETSI+GS+NFV+002+V1.2.1.">Network Functions Virtualisation (NFV); Architectural Framework; Research Report ETSI GS NFV 002 V1.2.1.</a> European Telecommunications Standards Institute. (ETSI). , (2014).</li><li>An Open Source NFV Management and Orchestration (MANO) software stack aligned with ETSI NFV. ETSI OSM Available from: <a target="_blank" href="https://osm.etsi.org/">https://osm.etsi.org/</a> (2019)</li><li>Nogales, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+Deployment+of+an+Open+Management+and+Orchestration+Platform+for+Multi-Site+NFV+Experimentation.">Design and Deployment of an Open Management and Orchestration Platform for Multi-Site NFV Experimentation.</a> IEEE Communications Magazine. 57 (1), 20-27 (2019).</li><li>Omnes, N., Bouillon, M., Fromentoux, G., Le Grand, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+programmable+and+virtualized+network+&amp;+IT+infrastructure+for+the+internet+of+things:+How+can+NFV+&amp;+SDN+help+for+facing+the+upcoming+challenges.">A programmable and virtualized network &amp; IT infrastructure for the internet of things: How can NFV &amp; SDN help for facing the upcoming challenges.</a> 18th International Conference on Intelligence in Next Generation Networks. , 64-69 (2015).</li><li>Rametta, C., Schembra, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Designing+a+softwarized+network+deployed+on+a+fleet+of+drones+for+rural+zone+monitoring.">Designing a softwarized network deployed on a fleet of drones for rural zone monitoring.</a> Future Internet. 9 (1), 8 (2017).</li><li>Garg, S., Singh, A., Batra, S., Kumar, N., Yang, L. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=UAV-empowered+edge+computing+environment+for+cyber-threat+detection+in+smart+vehicles.">UAV-empowered edge computing environment for cyber-threat detection in smart vehicles.</a> IEEE Network. 32 (3), 42-51 (2018).</li><li>Mahmoud, S., Jawhar, I., Mohamed, N., Wu, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=UAV+and+WSN+softwarization+and+collaboration+using+cloud+computing.">UAV and WSN softwarization and collaboration using cloud computing.</a> 3rd Smart Cloud Networks &amp; Systems (SCNS). , 1-8 (2016).</li><li>Gonz&#225;lez Bl&#225;zquez, L. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=NFV+orchestration+on+intermittently+available+SUAV+platforms:+challenges+and+hurdles.">NFV orchestration on intermittently available SUAV platforms: challenges and hurdles.</a> 1th Mission-Oriented Wireless Sensor, UAV and Robot Networking (MISARN). , (2019).</li><li>Nogales, B., Sanchez-Aguero, V., Vidal, I., Valera, F., Garcia-Reinoso, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+NFV+system+to+support+configurable+and+automated+multi-UAV+service+deployments.">A NFV system to support configurable and automated multi-UAV service deployments.</a> Proceedings of the 4th ACM Workshop on Micro Aerial Vehicle Networks, Systems, and Applications. , 39-44 (2018).</li><li>Nogales, B., Sanchez-Aguero, V., Vidal, I., Valera, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adaptable+and+automated+small+UAV+deployments+via+virtualization.">Adaptable and automated small UAV deployments via virtualization.</a> Sensors. 18 (12), 4116 (2018).</li><li>Hoban, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+ETSI+OSM+Community+White+Paper,+OSM+Release+FOUR:+A+Technical+Overview.">An ETSI OSM Community White Paper, OSM Release FOUR: A Technical Overview.</a> European Telecommunications Standards Institute. (ETSI). , (2018).</li><li>Quick start installation and use guide. Open Source MANO Release FOUR Available from: <a target="_blank" href="https://osm.etsi.org/wikipub/index.php/OSM_Release_FOUR">https://osm.etsi.org/wikipub/index.php/OSM_Release_FOUR</a> (2019)</li><li>Open Source Software for Creating Private and Public Clouds. OpenStack Available from: <a target="_blank" href="https://docs.openstack.org/ocata">https://docs.openstack.org/ocata</a> (2019)</li><li>OpenStack Installation Tutorial for Ubuntu. OpenStack Available from: <a target="_blank" href="https://docs.openstack.org/ocata/install-guide-ubuntu/">https://docs.openstack.org/ocata/install-guide-ubuntu/</a> (2019)</li><li>Linphone. An Open Source VoIP SIP Softphone for voice/video calls and instant messaging. Linphone Available from: <a target="_blank" href="https://www.linphone.org">https://www.linphone.org</a> (2019)</li><li>An Open Source Project to easily build and deploy secure video-conferencing solutions. Jitsi Available from: <a target="_blank" href="https://jitsi.org">https://jitsi.org</a> (2019)</li><li>Infrastructure for container projects. Linux Containers (LXC) Available from: <a target="_blank" href="https://linuxcontainers.org">https://linuxcontainers.org</a> (2019)</li><li>A Discrete-Event Network Simulator for Internet Systems. Ns-3 Available from: <a target="_blank" href="https://www.nsnam.org/">https://www.nsnam.org/</a> (2019)</li><li>Kernel-based Virtual Machine (KVM). A virtualization solution for Linux. Linux Available from: <a target="_blank" href="https://www.linux-kvm.org">https://www.linux-kvm.org</a> (2019)</li><li>Bridging &amp; firewalling. Linux Foundation Available from: <a target="_blank" href="https://wiki.linuxfoundation.org/networking/bridge">https://wiki.linuxfoundation.org/networking/bridge</a> (2019)</li><li>. Trafic. An open source flow scheduler Available from: <a target="_blank" href="https://github.com/5GinFIRE/trafic">https://github.com/5GinFIRE/trafic</a> (2019)</li><li>. Ubuntu Mate for the Raspberry Pi Available from: <a target="_blank" href="https://ubuntu-mate.org/raspberry-pi/">https://ubuntu-mate.org/raspberry-pi/</a> (2019)</li><li>Enabling LXC (Linux Containers) as virtualization technology. OpenStack Available from: <a target="_blank" href="https://docs.openstack.org/ocata/config-reference/compute/hypervisor-lxc.html">https://docs.openstack.org/ocata/config-reference/compute/hypervisor-lxc.html</a> (2019)</li><li>. Open Source MANO Information Model Available from: <a target="_blank" href="https://osm.etsi.org/wikipub/index.php/OSM_Information_Model">https://osm.etsi.org/wikipub/index.php/OSM_Information_Model</a> (2019)</li><li>ITU-T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ITU-T+Recommendation+G.114.+General+Recommendations+on+the+transmission+quality+for+an+entire+international+telephone+connection;+One-way+transmission+time.">ITU-T Recommendation G.114. General Recommendations on the transmission quality for an entire international telephone connection; One-way transmission time.</a> International Telecommunication Union - Telecommunication Standardization Sector. , (2003).</li></ol>

The authors have nothing to disclose.

One of the most important aspects of this experiment is the use of virtualization technologies and NFV standards with UAV platforms. NFV presents a new paradigm aiming to decouple the hardware dependency of the network functionalities, thus enabling the provision of these functionalities through softwarization. Accordingly, the experiment does not depend on the use of the hardware equipment specified in the protocol. Alternatively, different models of single board computers can be selected, as long as they are in line with the dimensions and the transport capacity of the UAVs and they support Linux containers.
Notwithstanding this flexibility in terms of hardware selection, all the content provided for the reproducibility of the experiment is oriented towards the use of open source technologies. In this context, the configuration aspects and the software tools are conditioned to the use of Linux as the operating system.
On the other hand, the experiment considers the interoperation of two different computational platforms (i.e., the UAV cloud platform and the core cloud platform) to provide a moderately complex network service. However, this is not strictly needed, and the protocol could be followed to support scenarios in which only the UAV cloud platform is involved.
In addition, the solution presented could potentially be used in other environments, where resource-constrained hardware platforms might be available with the needed capacity to execute virtualization containers (e.g., the Internet of Things, or IoT, environments). In any case, the applicability of this solution to different environments and its potential adaptations will require a careful study in a case-by-case basis.
Finally, it should be noted that the results presented have been obtained in a laboratory environment and with the UAV devices grounded or following a limited and well-defined flight plan. Other scenarios involving outdoor deployments may introduce conditions affecting the stability of the flight of the UAVs, and hence the performance of the IP telephony service.

One of the most coveted goals within the new era of the mobile communications (most commonly known as the 5th mobile generation or 5G) is to be able to provide robust information technology services in situations where the primary telecommunications infrastructure may not be available (e.g., due to an emergency). In this context, the UAVs are receiving increasing attention from the research community due to their inherent versatility. There are numerous works that use these devices as a cornerstone for the provision of a large variety of services. For instance, the literature has analyzed the capacity of these devices to build an aerial communication infrastructure to accommodate multimedia services1,2,3. Furthermore, prior research has shown how the cooperation among several UAVs can extend the functionality of different communication services such as surveillance4, collaborative search and rescue5,6,7,8, or agribusiness9.
On the other hand, the NFV technology has acquired great significance within the telecom operators as one of the 5G key enablers. NFV represents a paradigmatic change regarding the telecommunications infrastructure by alleviating the current dependency of network appliances on specialized hardware through the softwarization of the network functionalities. This enables a flexible and agile deployment of new types of communication services. To this purpose, the European Telecommunications Standards Institute (ETSI) formed a specification group to define the NFV architectural framework10. Additionally, the ETSI currently hosts the Open Source Mano (OSM) group11, which is in charge of developing an NFV Management and Orchestration (MANO) software stack aligned with the definition of the ETSI NFV architectural framework.
Given all the aforementioned considerations, the synergic convergence between UAVs and NFV technologies is currently being studied in the development of novel network applications and services. This is illustrated by several research works in the literature that point out the advantages of these types of systems14,15,16, identify the challenges of this convergence and its missing aspects, highlight future research lines on this topic17, and present pioneer solutions based on open source technologies.
In particular, the integration of NFV technologies into the UAV arena enables the rapid and flexible deployment of network services and applications over delimited geographic areas (e.g., an IP telephony service). Following this approach, a number of UAVs can be deployed over a specific location, transporting compute platforms as payload (e.g., small-size single board computers). These compute platforms would provide a programmable network infrastructure (i.e., an NFV infrastructure) over the deployment area, supporting the instantiation of network services and applications under the control of a MANO platform.
Notwithstanding the benefits, the realization of this view presents a set of fundamental challenges that needs to be carefully addressed, such as the appropriate integration of these compute platforms as an NFV infrastructure, using an existing NFV software stack, so that an NFV orchestration service can deploy virtual functions on the UAVs; the constraints in terms of the computational resources provided by the compute platforms, as the UAVs transporting them may typically present limitations in terms of size, weight, and computing capacity of payload equipment; the proper placement of the virtual functions onto UAVs (i.e., selecting the best UAV candidate to deploy a particular virtual function); the maintenance of the control communications with the UAVs in order to manage the lifecycle of the VNFs in spite of the potentially intermittent availability of network communications with them (e.g., caused by mobility and battery constraints); the limited operation time of the UAVs due to their battery consumption; and the migration of the virtual functions when a UAV needs to be replaced due to its battery exhaustion. These benefits and challenges are detailed in previous work18,19 that includes the design of an NFV system capable of supporting the automated deployment of network functions and services on UAV platforms, as well as the validation of the practical feasibility of this design.
In this context, this paper focuses on describing a protocol to enable the automated deployment of moderately complex network services over a network of UAVs using the NFV standards and open source technologies. To illustrate the different steps of the protocol, a re-elaboration of an experiment presented in Nogales et al.19 is presented, consisting of the deployment of an IP telephony service. To aid the reproducibility of this work, real flight is considered as optional in the presented procedure, and performance results are obtained with the UAV devices on the ground. Interested readers should be able to replicate and validate the execution of the protocol, even in a controlled laboratory environment.
Figure 1 illustrates the network service designed for this procedure. This network service is built as a composition of specific softwarization units (categorized within the NFV paradigm as Virtual Network Functions, or VNFs) and provides the functionality of an IP telephony service to users in the vicinity of the UAVs. The VNF composing the service are defined as follows:
<ul>
	<li>Access Point VNF (AP-VNF): This VNF provides a Wi-Fi access point to end-user equipment (i.e., IP phones in this experiment).</li>
	<li>IP telephony server VNF (IP-telephony-server-VNF): It is responsible for managing the call signaling messages that are exchanged between IP phones to establish and terminate a voice call.</li>
	<li>Domain Name System VNF (DNS-VNF): This VNF provides a name resolution service, which is typically needed in IP telephony services.</li>
	<li>Access router VNF (AR-VNF): provides network routing functionalities, supporting the exchange of traffic (i.e., call signaling in this experiment) between the IP phones and the telecommunication operator domain.</li>
	<li>Core router VNF (CR-VNF): provides network routing functionalities in the telecommunication operator domain, offering access to operator-specific services (i.e., the IP telephony server) and external data networks.</li>
</ul>
Moreover, Figure 1 presents the physical devices used for the experiment, how they are interconnected, and the specific allocation of VNFs to devices.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>AR. Drone 2.0 - Elite edition</td>
			<td>Parrot</td>
			<td></td>
			<td>UAV used in the experiment to transport the RPis and thus, provide mobility to the compute units of the UAV cloud platform.</td>
		</tr>
		<tr>
			<td>Bebop 2</td>
			<td>Parrot</td>
			<td></td>
			<td>UAV used in the experiment to transport the RPis and thus, provide mobility to the compute units of the UAV cloud platform.</td>
		</tr>
		<tr>
			<td>Commercial Intel Core Mini-ITX Computer</td>
			<td>Logic Suppy</td>
			<td></td>
			<td>Computer server which hosts the OpenStack controller node (being executed as a VM) of the experiment&#39;s UAV cloud platform. In addition, another unit of this equipment (along with the RPis) conforms the computational resources of the UAV cloud platform.</td>
		</tr>
		<tr>
			<td>Linux Containers (LXC)</td>
			<td>Canonical Ltd.</td>
			<td></td>
			<td>(Software) Virtualization technology that enables the supply of the Virtual Network Functions detailed in the experiment. Source-code available online: https://linuxcontainers.org</td>
		</tr>
		<tr>
			<td>Lithium Battery Pack Expansion Board. Model KY68C-UK</td>
			<td>Kuman</td>
			<td></td>
			<td>Battery-power supply HAT (Hardware Attached on Top) for the computation units of the UAV cloud platform (i.e., the Raspberry Pis). In addition, this equipment encompasses the case used to attach the compute units (i.e., the Raspberry PIs or RPis) to the UAVs.</td>
		</tr>
		<tr>
			<td>MacBook Pro</td>
			<td>Apple</td>
			<td></td>
			<td>Commodity laptop utilized during the experiment to obtain and gather the results as described in the manuscript.</td>
		</tr>
		<tr>
			<td>ns-3 Network Simulator</td>
			<td>nsnam</td>
			<td></td>
			<td>(Software) A discrete-event simulator network simulator which provides the underlying communication substrate to the emulation station explained in the &#34;Protocol&#34; section (more specifically in the step &#34;2. Validate the functionality of the softwarization units via Emulation&#34;). Source-code available online: https://www.nsnam.org</td>
		</tr>
		<tr>
			<td>Open Source MANO (OSM) - Release FOUR</td>
			<td>ETSI OSM - Open source community</td>
			<td></td>
			<td>(Software) Management and Orchestration (MANO) software stack of the NFV system configured in the experiment. Source-code available online: https://osm.etsi.org/wikipub/index.php/OSM_Release_FOUR</td>
		</tr>
		<tr>
			<td>OpenStack - Release Ocata</td>
			<td>OpenStack - Open source community</td>
			<td></td>
			<td>(Software) Open source software used for setting up both the UAV cloud platform and the core cloud within the experiment. Source-code available online: https://docs.openstack.org/ocata/install-guide-ubuntu</td>
		</tr>
		<tr>
			<td>Ping</td>
			<td>Open source tool</td>
			<td></td>
			<td>(Software) An open source test tool, which verifies the connectivity between two devices connected through a communications network. In addition, this tool allows to assess the network performance since it calculates the Round Trip Time (i.e., the time taken to send and received a data packet from the network). Source-code available online: https://packages.debian.org/es/sid/iputils-ping</td>
		</tr>
		<tr>
			<td>Power Edge R430</td>
			<td>Dell</td>
			<td></td>
			<td>High-profile computer server which provides the computational capacity within the core cloud platform presented in the experiment.</td>
		</tr>
		<tr>
			<td>Power Edge R630</td>
			<td>Dell</td>
			<td></td>
			<td>Equipment used for hosting the virtual machine (VM) on charge of executing the MANO stack. In addition, the OpenStack controller node is also executed as a VM in this device. Note that the use of this device is not strictly needed. The operations carried out by this device could be done by a lower performance equipment due to the non-high resource specifications of the before mentioned VMs.</td>
		</tr>
		<tr>
			<td>Prestige 2000W</td>
			<td>ZyXEL</td>
			<td></td>
			<td>Voice over IP Wi-FI phone, compatible with the IEEE 802.11b wireless communications standard. This device is utilized to carry out the VoIP call through the network service hosted by platform described for the execution of the experiment.</td>
		</tr>
		<tr>
			<td>Raspberry PI. Model 3b</td>
			<td>Raspberry Pi Foundation</td>
			<td></td>
			<td>Selected model of Single Board Computer (SBC) used for providing the computational capacity to the experiment&#39;s UAV cloud platform.</td>
		</tr>
		<tr>
			<td>SIPp</td>
			<td>Open source tool</td>
			<td></td>
			<td>(Software) An open source test tool, which generates SIP protocol traffic. This tool allows to verify the proper support of the signalling traffic required in an IP telephony service such as the one deployed in the experiment. Source-code available online: http://sipp.sourceforge.net</td>
		</tr>
		<tr>
			<td>Tcpdump</td>
			<td>Open source tool</td>
			<td></td>
			<td>(Software) An open source tool that enables the capture and analysis of the network traffic. Source-code available online: https://www.tcpdump.org</td>
		</tr>
		<tr>
			<td>Trafic</td>
			<td>Open source tool</td>
			<td></td>
			<td>(Software) An open souce flow scheduler that is used for validating the capacity of the network service deployed to process data traffic generated during an IP telephony call. Source-code available online at: https://github.com/5GinFIRE/trafic</td>
		</tr>
	</tbody>
</table>

automated deployment of an internet protocol telephony service on unmanned aerial vehicles using network functions virtualization

The Network Function Virtualization (NFV) paradigm is one of the key enabling technologies in the development of the 5th generation of mobile networks. This technology aims to lessen the dependence on hardware in the provision of network functions and services by using virtualization techniques that allow the softwarization of those functionalities over an abstraction layer. In this context, there is increasing interest in exploring the potential of unmanned aerial vehicles (UAVs) to offer a flexible platform capable of enabling cost-effective NFV operations over delimited geographic areas.
To demonstrate the practical feasibility of utilizing NFV technologies in UAV platforms, a protocol is presented to set up a functional NFV environment based on open source technologies, in which a set of small UAVs supply the computational resources that support the deployment of moderately complex network services. Then, the protocol details the different steps needed to support the automated deployment of an internet protocol (IP) telephony service over a network of interconnected UAVs, leveraging the capacities of the configured NFV environment. Experimentation results demonstrate the proper operation of the service after its deployment. Although the protocol focuses on a specific type of network service (i.e., IP telephony), the described steps may serve as a general guide to deploy other type of network services. On the other hand, the protocol description considers concrete equipment and software to set up the NFV environment (e.g., specific single board computers and open source software). The utilization of other hardware and software platforms may be feasible, although the specific configuration aspect of the NFV environment and the service deployment may present variations with respect to those described in the protocol.

Based on the data obtained during the execution of the experiment, in which a real VoIP call is executed and following the steps indicated by the protocol to gather this information, Figure 2 depicts the cumulative distribution function of the end-to-end delay measured between two end-user equipment items (i.e., a commodity laptop and an IP telephone). This user equipment represents two devices that are interconnected through the AP VNFs of the deployed network service. More than 80% of the end-to-end delay measurements were below 60 ms, and none of them were higher than 150 ms, which guarantees appropriate delay metrics for the execution of a voice call.
Figure 3 illustrates the exchange of DNS and SIP signaling messages. These messages correspond to the registration of one of the users in the IP telephony server (i.e., the user whose IP phone is connected to the AP VNF where the &#34;tcpdump&#34; tool is running) and to the establishment of the voice call.
Finally, Figure 4 and Figure 5 show the data traffic captured during the call. In particular, the first one represents the constant stream of voice packets transmitted and received by one of the wireless phones during the call, whereas the latter illustrates the jitter in the forward direction with an average value lower than 1 ms.
The results that were obtained in the experiment for the delay figures (end-to-end delay and jitter) satisfy the recommendations specified by the International Telecommunication Union - Telecommunication Standardization Sector (ITU-T)35. Accordingly, the voice call progressed with no glitches and good sound quality. This experiment validated the practical feasibility of using NFV technologies and UAVs to deploy a functional IP telephony service.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/60425/60425fig01.jpg" /> 
Figure 1: Overview of the network service, depicting the VNFs, the entities in which they are executed, and the virtual networks needed for the provision of the IP telephony service. <a href="https://www.jove.com/files/ftp_upload/60425/60425fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/60425/60425fig02.jpg" /> 
Figure 2: End-to-end delay. Representation of the end-to-end delay offered to the end-user equipment connected to the AP VNFs. For this purpose, the cumulative distribution function of the end-to-end delay has been computed from the measured RTT samples obtained with the &#34;ping&#34; command line tool. <a href="https://www.jove.com/files/ftp_upload/60425/60425fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/60425/60425fig03.jpg" /> 
Figure 3: User registration and call signaling messages. Illustration of the signaling traffic (DNS and SIP) exchanged to register a user in the IP telephony server and to create and terminate the multimedia session that supports the execution of the voice call. <a href="https://www.jove.com/files/ftp_upload/60425/60425fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/60425/60425fig04.jpg" /> 
Figure 4: Stream of voice packets. Representation of the voice traffic exchanged during the call, measured at one of the AP VNFs. (Abbreviations: RX = receive, RX = transmit, RTP = real-time transport protocol). <a href="https://www.jove.com/files/ftp_upload/60425/60425fig4large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/60425/60425fig05.jpg" /> 
Figure 5: Evolution of the network jitter during the call. Representation of the jitter experienced by the transmitted voice packets in the forward direction from one phone to the other. <a href="https://www.jove.com/files/ftp_upload/60425/60425fig5large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Watch this Scientific Journal Video about Automated Deployment of an Internet Protocol Telephony Service on Unmanned Aerial Vehicles Using Network Functions Virtualization at JoVE.com

Automated Deployment of an Internet Protocol Telephony Service on Unmanned Aerial Vehicles Using Network Functions Virtualization

The objective of the described protocol is twofold: to configure a network functions virtualization environment using unmanned aerial vehicles as computational entities providing the underlying structure to execute virtualized network functions and to use this environment to support the automated deployment of a functional internet protocol telephony service over the aerial vehicles.

The Network Function Virtualization (NFV) paradigm is one of the key enabling technologies in the development of the 5th generation of mobile networks. ...

This protocol can aid in the automated deployment of telecommunication services over constrained devices, such as with telephony service provided through an aerial network of unmanned aerial vehicles. The advantage of this solution is that it facilitates in the rapid deployment of services over the limited geographic areas, for which communication infrastructures may be unavailable or insufficient. This protocol has been defined within the research area on the third generation of mobile networks and it is based on state of the art normal function utilization technologies.This method has been demonstrated using the advanced prototypes available here at 5TONIC, the European leading laboratory in 5G, but it can be demonstrated also without our 5G virtual systems. To verify the correct setup of a UAV cloud platform, access the Administrator, System, System Information tab using the appropriate login information and click in the Computing Service and Network Agent sections to check that the status of the displayed items is up. To configure an experiment, download the VNF images that implement the different components of the IP telephony service from the experiment repository.To upload the VNF images to their correspondent VIM, click Create Image and create an image using the displayed form. After uploading the images for each corresponding VIM, download the VNF descriptors of the experiment from the experiment repository and sign in to the OSM graphical user interface with the administrator credentials. Drag and drop the descriptors into the VNF Packages tab.Then, download the NSD from the experiment repository and drag and drop the NSD into the NS Packages tab of the OSM graphical user interface. To add a VIM account for UAV cloud platform VIM and for the core cloud platform VIM, in the VIM Accounts tab, click plus New VIM and complete the displayed form with the requested information for both VIMs. To initiate an experiment, access the OSM command line interface and deploy the network service.Type the command to execute the network service in the command line interface specifying the VIM that will be used to host each VNF. When the OSM graphical user interface indicates a successful network service deployment, switch on the UAVs and login to the UAV flight control application. Then, control the flight of each UAV to stably maintain the vehicle at an intermediate height and to avoid any turbulence caused by the rotation of the motors close to a surface.To prepare an IP phone to carry out a call, connect a wireless voice over IP phone to one of the access points offered by the network service. Then, click Advanced and TCP/IP and check that the IP and router addresses are correctly configured. To enable the appropriate exchange of signaling messages with the IP telephony server, open the app and click Assistant, and use a SIP account to create a user account.Then specify the host name of the IP telephony server, VNF. If using a handheld voice over IP phone, take similar steps to what was just shown. To create an entry in an IP phone book, click Options and enter the address or phone number in the window.Once the experiment presents the call participants in their respective locations, one of the users can initiate an IP telephony call. To initiate the call to the other party, press the Call button. When the other IP phone starts ringing, use the Call button to accept the incoming call.To collect the experimental results, connect a commodity laptop to one of the wireless access points and run the ping command line tool to the IP address that the phone connected to the other access point over 180 seconds. Once the connection has established with the access point, verify the IP connectivity with the IP phone, and save the round trip time measurements. To capture the traffic exchanged during the IP call, execute the TCP dump command line tool in one of the running access point VNFs and save this traffic into a file, enabling the writing flag of the command line tool at the execution time and specifying the name of the file.Then perform a new IP telephony call and maintain the call for a specific period of time before terminating the call. Here, data from a real voice over IP call demonstrates the cumulative distribution function of the end-to-end delay measured between two end user equipment items. More than 80%of the end-to-end delay measurements were below 60 milliseconds in this analysis and none of the measurements were higher than 140 milliseconds, guaranteeing the appropriate delay metrics for the execution of a voice call.Here, an exchange of the DNS and SIP signaling messages is illustrated with the messages corresponding to the registration of one of the users in the IP telephony server and to the establishment of the voice call. In this representative graph of data traffic captured during a call, a constant stream of voice packets transmitted and received by one of the wireless phones during the call is shown. In this graph, the jitter in the forward direction of the data traffic, with an average value lower than 1 millisecond, can be observed.When reproducing this protocol, it is important to consider the utilization of single-port computers to execute the virtualization containers. This protocol could potentially be used in other environments in which resource constrained devices might be available, for instance, in the northeast environments. If the protocol includes a flight procedure experimenter, so be sure to follow the appropriate security measures and the corresponding regulatory statement.

Research

JoVE Journal

Engineering

Setting Limits on Supersymmetry Using Simplified Models

Experimental limits on supersymmetry and similar theories are difficult to set because of the enormous available parameter space and difficult to ...

Experiments on Ultrasonic Lubrication Using a Piezoelectrically-assisted Tribometer and Optical Profilometer

Friction and wear are detrimental to engineered systems. Ultrasonic lubrication is achieved when the interface between two sliding surfaces is vibrated at ...

Data Acquisition Protocol for Determining Embedded Sensitivity Functions

The effectiveness of many structural health monitoring techniques depends on the placement of sensors and the location of input forces. Algorithms for ...

Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery

Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery

We demonstrate a method for electrochemical testing of an aprotic Li-O2 battery. An aprotic Li-O2 battery is made of a Li-metal anode, an aprotic ...

Measuring Spray Droplet Size from Agricultural Nozzles Using Laser Diffraction

When making an application of any crop protection material such as an herbicide or pesticide, the applicator uses a variety of skills and information to ...

Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation

We present a protocol for fabricating 1-D Photonic Crystal (PhC) cavities on subwavelength-diameter tapered optical fibers, optical nanofibers, using ...

Measurements of Soil Carbon by Neutron-Gamma Analysis in Static and Scanning Modes

The herein described application of the inelastic neutron scattering (INS) method for soil carbon analysis is based on the registration and analysis of ...

The Modular Design and Production of an Intelligent Robot Based on a Closed-Loop Control Strategy

Intelligent robots are part of a new generation of robots that are able to sense the surrounding environment, plan their own actions and eventually reach ...

An Available Technique for Preparation of New Cast MnCuNiFeZnAl Alloy with Superior Damping Capacity and High Service Temperature

Manganese (Mn)-copper (Cu)-based alloys have been found to have&#160;damping capacity and can be used to reduce harmful vibrations and noise effectively. ...