The 5G ecosystem is comprised of the cellular 5G System, as well as a managed and orchestrated infrastructure providing virtualized network and service functions. The automotive industry with its stringent requirements for connected vehicles is a promising and yet challenging consumer of such 5G ecosystem. Deployment of service instances at distributed cloud resources of cellular network infrastructure edges enables localized low-latency access to these services from moving vehicles but comes along with challenges, such as the need for fast reconfiguration of the distributed deployment according to mobility pattern and associated service and resource demand. In this paper, we investigate a solution for the collaborative orchestration of services for Connected, Cooperative and Automated Mobility (CCAM) within such 5G ecosystem. A key objective is the service continuity for a highly dynamic automotive scenario, achieved by the associated management and orchestration of these services in distributed edge clouds. The proposed solution leverages a multi-tier orchestration system as well as localized management and protocol operations for collaborative edge resources. By means of both analytical and experimental evaluations, the paper draws conclusions on the gain in accelerating orchestration decisions and enforcements, while balancing associated protocol and computational load over the highly distributed and multi-layered orchestration system.

5G has opened up possibilities of introducing new use cases and business models that could not be perceived before. In the context of public safety, 5G offers immense opportunities towards enhancing mission success and situation awareness during emergency management. This paper introduces Back-Situation Awareness (BSA) application enabling early warning/notification to vehicles of an approaching emergency vehicle indicating its presence and the time it will arrive. Such an application is expected to give drivers enough time to create a safety corridor for the emergency vehicle to pass through safely and unhindered. We provide details on the system and application design of the BSA application leveraging Multi-Access Edge Computing (MEC) systems that complement the 5G mobile communication system. An evaluation of the application is provided by using data measurements and indicating the accuracy of the computation and notification of the Estimated Time of Arrival (ETA) based on the ETSI C-ITS protocol messages.

The 5th generation of the cellular mobile communication system (5G) is in the meantime stepwise being deployed in mobile carriers' infrastructure. Various standardization tracks as well as research activity are investigating the exploitation of the very flexible 5G system architecture for customized deployments, meeting requirements of the vertical industry, such as for automotive, factory, or smart city. A very common base is a cloud-native development and decentralized deployment of the 5G system along with services in distributed resources per the Multi-Access Edge Computing (MEC) architecture to locate services topologically close to (mobile) users, e.g. along public roads, and to enable low-latency communication with local services. Automated management of such a distributed deployment in an agile environment is a prerequisite. This paper investigates the use of Recurrent Neural Networks (RNN) for accurate user mobility prediction in an automotive scenario. By the use of simulated vehicular traffic, a suitable RNN configuration using Long Short-Term Memory (LSTM) has been found, which provides accurate prediction results. Proof of value has been accomplished by an experimental decision algorithm, which balances the use of available distributed resources through service scale, migration or replication decisions while meeting mobile users' expectation on the experienced service quality.

The interest in extending the range of mobile networks by means of drones, which carry a cellular radio base station or even a complete mobile core, is continuously increasing in research as well as in industry. Whereas the asset in such solutions is well motivated, various practical aspects are not fully considered, such as weight, power consumption and associated flight time of such drones, which usually carry limited and expensive mobile energy resources. In this paper we leverage various advantageous architectural and operational aspects of a 5G Mobile Core and propose the use of a low-cost system-on-chip solution on board of a drone to realize a flying 5G User Plane Function, which serves as data plane anchor to mobile devices attaching to the cellular base station co-located with the drone and enables offloading traffic to services, which can run on the system-on-chip board as well. We prototyped a standard-conform User Plane Function by means of the open source fd.io project for Vector Packet Processing and enabled mobile access to flying lightweight mobile edge services. The paper describes how the drone system operates with the architecture backend in the fixed infrastructure and presents experimentally determined performance figures, comparing the developed low-costs flying edge services with a setup, which deploys the 5G User Plane Function as well as services in the fixed infrastructure.

The ambitious objectives of the 5th Generation (5G) mobile communications subtend a profound change in the way mobile networks are designed, both in the infrastructural aspects and in the operational protocols. Network slicing is considered as a promising deployment option to enable tailored and logically separated resources and value-enabled platforms to the vertical industries. This paper introduces the concept of a lean packet system in support of a tailored and flexible data plane to better align the provisioned network (slice) with the requirements of the vertical industry. The described solution provides a great match between deployment flexibility, resources utilization and routing efficiency. The design of an experimental testbed is described and results from an experimental evaluation of routing efficiency against alternative solutions confirm the value of our concepts.

In this paper we discuss the major modifications required in the current LTE network to realize a decentralized LTE architecture and develop a novel IP mobility management solution for it. The proposed solution can handle traffic redirecting and IP address continuity above the distributed anchor points in a scalable and resource efficient manner. Our approach is based on the NAT (Network Address Translation) mechanism, which is a well- known and widely used procedure in the current Internet. We extend the NS3-LENA to implement a decentralized LTE network as well as the proposed scheme. The evaluation results show that the proposed solution efficiently fulfills the functionality and performance requirements (e.g.,latency and signaling load) related to the mobility management.

The proliferation of new mobile- and machine-type devices with different traffic and resources utilization patterns and an increasing total number of devices raise demand for mobile communication network components that provide elasticity without incurring a high CAPEX/OPEX. Vendors of mobile infrastructure components are adopting technology for the virtualization of network functions and for Software Defined Networking to build suitable products that can render carriers' networks with the required resiliency and elasticity. Virtualized network functions can easily scale and provide additional resources to handle load associated with the incoming registrations during mobile devices' attachment to the network. This paper proposes a mechanism that extends traditional scaling of virtualized network function by scaling mobile communication gateways' Data-Plane functions during runtime. Already established mobile device context information and associated data traffic is offloaded from an instance of a network function component to avoid overload and failure of that component. The proposed mechanism for runtime offload enables fast Data-Plane scaling during unexpected peaks of Data-Plane traffic and provides seamless service continuity to the mobile subscribers. We used an experimental approach to validate the proposed mechanism. The results of selected test cases conclude this paper.

The recent proliferation of powerful smartphones have enabled an explosive increase in demand for mobile video (and other content) download services. In order to meet the users' demand and quality expectation, the mobile network operators tend to deploy and operate their own Content Delivery Network (CDN) within their existing network infrastructure. This situation has given rise to new set of research and standardization challenges to address this latest trend of expanding role/scope of network infrastructures and resource demands. New methods and strategies need to be devised for resource-efficient and costeffective delivery of such high volume content to mobile users. In this paper we motivate the enabling of runtime relocation of mobility gateways and CDN Serving Points for maintaining low costs for mobile content delivery. By means of a detailed simulative study, we evaluate the cost of delivering content to mobile users while taking into consideration different topologies, user mobility and content size. We demonstrate that the gain that is achieved in terms of cost saving justify taking additional protocol complexity to support runtime relocation of Mobile CDN serving points.

Mobile carriers are currently facing the tremendous challenge of coping with the rapid data traffic growth stemming from smart phones and data dongles. Recent studies have shown that caching of high volume content within carrier networks has the potential of substantial cost savings in network resources. This paper analyzes the effectiveness of caching in mobile carrier networks, being enabled by distributed mobility gateways and content caches, and estimates how much cost savings an operator can expect for different cache deployment scenarios. The study considers various backhaul network characteristics and several content replication strategies.

The Internet Engineering Task Force (IETF) recently approved the proxy mobile IPv6 standard for network- based localized mobility management. Unlike host-based mobility management, the network handles mobility signaling on behalf of mobile nodes in proxy mobile IPv6, i.e., the mobile nodes are not involved in mobility management, hence have no control on handover-related signaling. The current specification of proxy mobile IPv6 defines basic operations for registration, deregistration, and tunnel management. As mobile nodes have no control on mobility management, the timing for handover signaling is not synchronized with the mobile node's ability to send and receive packets on the handover target link. This turns out to be an issue for mobile nodes being equipped with multiple network interfaces and performing handover between these access technologies (inter-technology handover), as the configuration of the target network interface and the associated link takes time. In this work, we investigate technical issues that occur during an inter-technology handover in proxy mobile IPv6. We demonstrate through experimental performance evaluation that an inter-technology handover in proxy mobile IPv6 can cause considerable handover delay and packet loss. We propose an efficient extension to proxy mobile IPv6 to eliminate delay and packet loss during an inter-technology handover. We demonstrate the effectiveness of the proposed extension through an experimental performance evaluation.

Various standardization development organizations consider network-based mobility management in future mobile communication networks to complement host-based mobility management. Proxy mobile IPv6 is currently being standardized to suit basic requirements of network-based mobility management, such as no-host involvement in the location update procedure. In this paper, we want to motivate advanced operation of multi-mode mobile terminals, which attach to a proxy mobile IPv6 enabled network through multiple network interfaces simultaneously. We propose extensions to proxy mobile IPv6 enabled networks to allow simultaneous operation of a device's multiple interfaces, which have the same IPv6 address configured, while being registered with a single mobility anchor. Along with a description of these extensions, this paper comprises results of measurements we could perform in a real test-bed to show the performance gain of two target scenarios for flow distribution and bandwidth aggregation.

Future Internet Protocol mobile communications systems will implement solutions for network-based mobility management to enable mobility for terminals, which do not support Mobile IP. The Internet Engineering Task Force is specifying a base protocol for network-based mobility, which supports registration, deregistration and handover. Support for optimization will be considered in a subsequent standardization step. This paper proposes a solution to enable support for route optimization, being under control of the mobility anchor of the network-based mobility domain. The route optimization protocol solution has been specified with the objective to cope with difficult scenarios, which can occur in a network-based mobility enabled system. The protocol has been implemented and evaluated based on a base protocol specification, taking future porting into the final standard base protocol into account. Important characteristics have been obtained from a hybrid test- bed, which comprises physical and virtual network entities. The results show, that the proposed protocol sets up and maintains optimized routes efficiently.

Privacy and security are important features for the future mobile wireless Internet since users expect a privacy level comparable to that of today's cellular networks. Separating identifiers from locators is a current practice in today's new network protocols and is a small step on the right direction. However, the separation must be maintained in the presence of an intruder who eavesdrops or manipulates the traffic. In this paper we present a generic framework that targets these problems at the network layer. We further instantiate this framework with an example architecture using well-known protocols which support mobility.

Mobile communication systems increasingly adopt Internet Protocol solutions for transport of control and data traffic. To optimize scalability of the mobile communication infrastructure and to save mobile energy resources, mobile devices can set their network interface to power save mode, such as for instance supported by the IEEE 802.11 technology, and refrain from sending superfluous location information towards the network in case the device is idle. Such systems utilize paging to locate and reactivate mobile devices in power save mode. In this paper, we show how mobile terminal power saving efficiently complements IP paging in an IEEE 802.11-enabled network. By means of simulations, we evaluate and compare a mobile terminal's power consumption due to mobility management within a Mobile IPv6 network with and without paging and power save mode support. The results show that IP paging with complementary power save mode support harmonizes efficient location tracking with optimized energy resource usage, while taking requirements on routing delay constraints into account.

Mobile communication systems increasingly adopt Internet protocol solutions for transport of control and data traffic. To optimize scalability of the mobile communication infrastructure as well as to save scarce radio bandwidth and mobile energy resources, mobile devices can enter a power save mode and refrain from sending superfluous location information towards the network in case the device is idle. Such systems utilize paging to locate and reactivate mobile devices in power save mode, as well as to initiate re-establishment of routing information in the network. The well accepted wireless LAN standard IEEE802.11 supports mechanisms for power saving while a mobile terminal is associated with a particular access point. But paging control of mobile devices in power save mode beyond the scope of a single access point is not part of the standard IEEE802.11 application. In this paper, we propose a mechanism to integrate and utilize existing IEEE802.11 power save mode with an IP paging architecture and protocol without the need to modify the IEEE802.11 standard. In addition to the IP paging protocol operation, the proposal covers an appropriate addressing and identification scheme, which can be utilized for other access technologies as well. An analytical evaluation of energy and paging delay costs allows estimation of the proposed mechanism's efficiency, which might be sub-optimal for high load conditions, but appropriate to support migration scenarios towards future heterogeneous access mobile communication networks.

This paper presents a Mobile IPv6-based overlay network architecture for heterogeneous environments, designed entirely based on IPv6, that aims to be implemented seamlessly irrespectively of the supporting network infrastructure. All transmission technologies are handled at the physical and data-link layers, imposing IPv6-based protocols for all higher layer communications and signaling. The architecture builds on Mobile IPv6 including improved fast handover, and integrates quality-of-service and authentication, authorization, accounting, and charging control per user. The most critical issues of the proposed architecture, mainly related to the handover process, were subject of a performance evaluation via ns-2 simulations. Finally, a field trial of the system was implemented, overlaying part of the GEANT infrastructure between Madrid and Stuttgart, which results are presented here.