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Distributed Heuristic Algorithms for RAT Selection in Wireless Heterogeneous Networks

Distributed Heuristic Algorithms for RAT Selection in Wireless Heterogeneous Networks

‡ University of Rennes I - IRISA, France § Universit´e de Versailles - PRISM Laboratory, France Abstract—In wireless heterogeneous networks, one of the most challenging problems is Radio Access Technology (RAT) selection that must be designed to avoid resource wastage. In this paper we adopt a hybrid model for RAT selection where the system allocates the downlink traffic between two different technologies in order to enhance global performance. We study the case of an integrated hybrid Wireless Local Area Network environment where the challenge we face is the high computational complexity necessary to obtain the global optimal solution. Therefore, we propose four distributed heuristic algorithms for RAT selection, where two of them are based on the distance between the user and the access points (APs), namely, distance based and probabilistic distance based algorithms. While the two others schemes are based on the peak rate that each user receives from these APs (peak rate based and probabilistic peak rate based algorithms). Results show that the proposed algorithms give efficient results compared to the optimal one depending on the spatial users distribution. Moreover these algorithms have a low computational complexity which makes them more advantageous compared to the optimal scheme in presence of a large number of users.
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2017 — Analyzing coalitions in wireless heterogeneous networks and their economic aspects

2017 — Analyzing coalitions in wireless heterogeneous networks and their economic aspects

of service (QoS). The better service providers offer, the more subscribers they attract. To be successful, providers need to expand their coverage areas and provide a better quality of ser- vice in terms of higher connection speed, reliability, coverage size, etc. However, the monetary resources of each provider are limited and the networks cannot be expanded or upgraded in- stantly. This fact motivates us to study a cost-effective approach that can help the providers in a market of heterogeneous networks (HetNets) to increase their revenue and improve the quality of service while the incurred costs are minimized. One approach that has been considered in several works, e.g., (Singh et al., 2011, 2012b), is to form coalitions in homogeneous wire- less markets. These works try to utilize the concepts of game theory and increase the profit of providers. This approach is also consistent with the free roaming plans that are offered by sev- eral operators. For example, since June 2015, Indian operator BSNL offers free national wide roaming plans in cooperation with MTNL (BSNL). Sprint offers a Global Roaming plan which includes free unlimited data and text across its worldwide participating networks including the ones from Canada, Mexico, and Latin America (Sprint, 2016). We aim to expand this idea to the field of heterogeneous operators that offer complementary strengths in terms of coverage, technologies, tiered service speeds, and pricing. Due to technological differences and imple- mentation costs, it is critical for the operators to assess the potential gain before committing to form a coalition. Our work is based on an analytical structure that covers both competitive and cooperative states of HetNets market. Based on this structure, we derive coalition formation models for heterogeneous wireless networks that define roles and interactions of the main deci- sion makers in the market, namely, users, providers and regulator. It should be noted that we try to avoid the formation of the grand coalition since it leads to a monopoly which is prohibited by regulatory units. Thus, our goal is to maintain competition among providers in the form of established coalitions.
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Integrating Multi-Modal Messages across Heterogeneous Networks

Integrating Multi-Modal Messages across Heterogeneous Networks

1. Introduction A new era of communications is commencing with the development of Personal Communication Systems (PCS) that will allow communication with persons wherever they are, support personal mobility from one terminal to another, support mobile terminals, support user customized services, and a universal personal identification number. This paper addresses the problems associated with the management of personal messages across heterogeneous networks and considers this as an important functionality of a PCS system. This field of study we call ÒSeamless MessagingÓ (SM) and primarily involves the integration of the following key technologies, information filtering, and telematics. The SM paradigm allows the recipient of the message be located if necessary and the message tailored to the recipientÕs active target device. SM allows users to work in distributed personal workspaces and have messages created and delivered how, when, where, and if they wish them to be. In this environment wireless networks will be essential in supporting mobile and remote access.
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Multi-User collaborative scheduling in 5G massive MIMO heterogeneous networks

Multi-User collaborative scheduling in 5G massive MIMO heterogeneous networks

In 4G, the enhanced Inter Cell Interference Coordination (eICIC) feature was introduced to enhance capacity and mitigate interference in heterogeneous networks with SCs deployment [4] [5]. The interference reduction is obtained by means of the Almost Blank Subframe (ABS) feature that mutes almost all macro Base Station (BS) transmissions on a certain portion of the subframes, thus letting SCs serve their users with reduced interference. However with M-MIMO, only part of the users are served simultaneously by the focused beams, thus making ABS of limited use.

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2017 — Distributed radio resource allocation in wireless heterogeneous networks

2017 — Distributed radio resource allocation in wireless heterogeneous networks

The SE is a state in which all agents satisfy their QoS constraints. Thus, the pure-strategy SE of (Perlaza et al., 2012b) is an NE of a normal form game with binary utilities where all agents receive a utility of one. From this perspective, radio devices are no longer modeled by agents that maximize their individual benefit, but by agents that aim to satisfy their individual constraint. This new approach was adopted to model the problem of dynamic spectrum access in (Ren et al., 2015; Ellingsæter, 2014) and SCs in (Perlaza et al., 2012a). Other applications of SE are reported for instance in the case of collaborative filtering in (Xu et al., 2014b). In (Goonewardena & Ajib, 2016) it is shown that the normal-form games discussed in (Southwell et al., 2014), where the agent has a dormant action, have satisfaction-form representations, such that their pure-strategy NEs coincides with the SEs. However, this equilibrium notion of SE as introduced in (Perlaza et al., 2012b) presents several limitations. As pointed out in (Southwell et al., 2014), the notion of SE is too restrictive. Simultaneously satisfying the QoS constraints of all agents might not be always feasible. Hence, the existence of an SE is highly constrained, which limits its application to wireless networks. This same limitation is observed if the generalized NE (GNE) is employed to solve the problem and in fact (Perlaza et al., 2012b) demonstrates that the GNE is more restrictive than their proposed SE. The GNE too cannot exist even if one agent cannot satisfy its constraint (Scutari et al., 2010).
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Utility-based Message Replication for Intermittently Connected Heterogeneous Networks

Utility-based Message Replication for Intermittently Connected Heterogeneous Networks

1 we depict the improvement in the delivery delay of greedy Spray and Wait “SW”, when message replicas are handed over using LSF Spraying only to nodes that have a last-encounter timer v[r]

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A Hybrid Approach for RAT Selection in Wireless Heterogeneous Networks

A Hybrid Approach for RAT Selection in Wireless Heterogeneous Networks

coverage area. In fact, the distributed decision is very close to the optimal one, and it will associate the clients to the adequate wireless access network so that we will have the lowest cost. The hybrid approach’s algorithm that performs periodic interventions to adjust client association profile has its performance degraded for equitable distributions of peak rates between the two wireless access networks. In fact, the distributed approach’s decision is very close to the centralized decision. Thus, the periodic intervention (to apply the centralized approach’s association profile) will adversely affect the performance of the system over time. Therefore, the hybrid solution cost will be greater than that of the centralized approach (and even greater than that of the distributed approach) when the client peak rates distribution is equitable between the two wireless access networks. The hybrid approach’s algorithm shows better performance than the distributed one for extreme peak rates distributions since the latter’s decision is not close to the optimal one. In this case, the intervention will be interesting since it will adjust the client association profile to the optimal one, which will reduce the cost and improve the performance.
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2016 — Mobility and resource management for 5G heterogeneous networks

2016 — Mobility and resource management for 5G heterogeneous networks

In the third part, the admission and power control problem of a general heterogeneous network (HetNet) consisting of several small cells (SCs) is solved. Compared to the first two parts of this work, the system is expanded from a multi-hop RS to a general SC context. This part therefore focuses only on the access link problem, assuming the capacity of the SC backhaul links are large enough not to be bottlenecks. This part mainly deals with the problem of how to maximize the number of admitted users in an overloaded system while minimizing the transmit power given a certain QoS level. First, the problem is formulated to address concerns about QoS requirements in a better way. Second, a Voronoi-based user association scheme for maximizing the number of admitted users in the system under QoS and capacity limitation constraints is proposed to find near-optimal solutions. Finally, a two- stage algorithm is presented to address the joint admission and power control problem in a downlink heterogeneous SC network. In particular, the first stage proposes a dynamic call admission control policy that considers the SC load and call-level QoS while also helping to keep the system from being overloaded. The second stage presents an adaptive power allocation strategy that considers both user distribution and the density of SCs in HetNets. Finally, the proposed solutions are evaluated using extensive numerical simulations, and the numerical results are presented to provide a comparison with related works found in the literature.
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DNN Based Beam Selection in mmW Heterogeneous Networks

DNN Based Beam Selection in mmW Heterogeneous Networks

Keywords: millimeter wave · beam selection · deep neural network · heterogeneous network · sub-6GHz. 1 Introduction Millimeter Wave (mmW) communication is considered as a promising technique to solve the unprecedented challenge of increasing demand for high data rates in future cellular networks. However, it suffers from limited coverage and in the ultra-dense environment it is significantly prone to blockages such as high density objects like walls, glass, humans, etc. Thus, in-order to provide flexible coverage and minimize the infrastructural cost, it is proposed that mmW networks will be deployed in a multi-tier heterogeneous network, where multiple small cell mmW base stations (BSs) coexist with multiple legacy sub-6GHz macro BSs [9].
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Permeability fluctuations in heterogeneous networks with different dimensionality and topology

Permeability fluctuations in heterogeneous networks with different dimensionality and topology

at the smallest scale S 0 is completely known and that it is bounded by k min and k max (a reasonable assumption since the system considered is not infinite), the permeability of any sample of volume larger than S 0 must be lower (respectively, greater) than k max (respectively, k min ). Note that this must be true whether the spatial distribution of k is correlated or not. The extrema are actually reached only in homogeneous volumes of material with k = k max (or k min ) at every point. Consequently, the successive k distributions at increasing scales must be entirely included within each other (i.e., nested distributions) as illustrated in Figure 8a (showing the k distributions obtained here in 2D square networks of size 4  4, 8  8, 16  16 and 32  32 with distribution A4). The k distributions reported in Tidwell and Wilson [1997, 1999a, 2000] were not nested (they were similar to the distributions illustrated in Figure 8c), imply- ing that the measurements of k with the smallest R used in these studies were statistically biased. Notice that the absence of this anomaly in the case of volcanic tuff coincided with a negative scale dependence of hki a . It seems likely to us that the anomalous behavior of the sandstone blocks is related to the rock rather than to the experimental method. Perhaps, quarrying produced a thin damaged layer at the surface of relatively hard rocks like Berea and Massillon sandstones whereas this did not occur in softer volcanic tuff. Alternatively, salt precipitation due to weathering may reduce permeability inside a thin layer at the rock surface [e.g., Evans, 1969; Jeannette, 2000]. Note that the volcanic tuff block was indeed cut very shortly before the permeability measurements were made (no such information was specified for the sandstone blocks).
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On Ranking Relevant Entities in Heterogeneous Networks Using a Language-Based Model

On Ranking Relevant Entities in Heterogeneous Networks Using a Language-Based Model

Conclusion and Future Work In this article, we proposed a bi-type entity ranking algo- rithm that aims to rank jointly documents and authors in a bibliographic network regarding a topical query. More specifically, the BibRank ranking model relies mainly on evidence sources issued from both content-based and network-based features. These features allow us to have a sense of the appropriateness of author’s scientific production and document topic regarding the general description of the subject research held by the query. According to PageRank general form, partial scores are aggregated and propagated through the heterogeneous network. Experiments undertaken on the CiteSeerX collec- tion demonstrate the effectiveness of the BibRank algorithm in comparison to state of the art ranking models. Improve- ments achieved using automatic generated queries based on LDA algorithm are estimated between 7% and 113% for document ranking and between 14% and 38% for author FIG. 11. NDCG at different document ranking.
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Algorithms for subnetwork mining in heterogeneous networks

Algorithms for subnetwork mining in heterogeneous networks

1 Introduction The use of communication, social and telecommunication networks has dramatically increased recently, resulting in new prominent applications of network analysis. In addition to these real-world applications, net- work representations of new types of data - and particularly biological data - highlight the drastic need for a new, multi-dimensional, type of (sub)network mining in which several networks, representing several re- lations between the same objects, are simultaneously investigated for the extraction of a multi-dimensional pattern [5,13,15].

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QoE-aware Network Selection in Wireless Heterogeneous Networks

QoE-aware Network Selection in Wireless Heterogeneous Networks

The main idea is to use quality of experience of ongoing users in candidate networks as an indicator to select the best network for connection.. We have implemented and tested our mechan[r]

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Converged video delivery over heterogeneous networks

Converged video delivery over heterogeneous networks

4.) Home IP Address: This is the address assigned by the streaming server to which the server will stream all traffic. This is attached to a virtual interface which gets packets f[r]

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Edge computing-based access network selection for heterogeneous wireless networks

Edge computing-based access network selection for heterogeneous wireless networks

Network Function Virtualization ( NFV ). They develop a state sharing mechanism across different data centers even in presence of firewall/network encapsulation. In [ 107 ], the authors propose novel local streaming service concepts and business models based on Mobile Edge Computing by utilizing a relevant theoretical framework. In [ 108 ], the authors introduce ME-VoLTE, an MEC-based video telephony system that aims to reduce power consumption of mobile devices. To this end, encoding efforts during video calls are offloaded to nearby MEC servers. In [ 109 ], the authors study energy-efficient computation offloading mechanisms for MEC in 5G heterogeneous networks. Then an optimization problem is formulated to minimize the energy consumption of the offloading system, where the energy cost of both task computing and file transmission are taken into consideration. However, in the literature above, few studies address this issue of HTTP-based adaptive streaming by leveraging MEC approach. In [ 110 ], an architecture for optimizing HTTP-based multimedia delivery in mobile networks is studied. The authors propose a network-assisted approach based on adaptive HTTP streaming with multi-layer encoding and MEC. They introduce a mobile edge-DASH adaptation function (ME-DAF) located within the Cloud Radio Access Network ( C- RAN ). However, their architecture still considers the Channel Quality Indicator ( CQI ) for the selection strategy, which may represent an important signaling overhead.
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IP mobility enhancements for heterogeneous wireless networks

IP mobility enhancements for heterogeneous wireless networks

5.5 Chapter Summary In this chapter we introduced a sensor node deployment assisted extension for eHIP in order to provide a location estimation system for mobile node. This extension introduce a new network element named as Network Location Server (NLS) to provide location estimation function. Mobile nodes obtain a next appropriate PoA estimation related to their trajectory inside the network. This can provide proactive association with next AP by using eHIP’s regular version. The mobile node’s newly added sensor node detection capability offer to detect the neighboring sensor nodes identity information due to its reading range. The number of detected sensor nodes mainly depends on architectural design of sensor deployment in the network. Several parameters have been examined by extensive simulations. Moreover, the new network element (NLS), employed positioning techniques and new system functions are introduced. A simple but descriptive theoretical analyses are also done for total elapsed time needed for sensor assisted movement detection phase and energy consumption of mobile node during this extra features. This proposal show us that it is possible to benefice from network topology and environment to improve the mobility management of mobile node especially in heterogeneous networks.
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Algorithmic Aspects of Heterogeneous Biological Networks Comparison

Algorithmic Aspects of Heterogeneous Biological Networks Comparison

The main comparative approaches considered so far focus on homogeneous networks using networks alignment (see, among others, [10,11,18,20,5,2,21,12]). Such methods are powerful for detecting conserved modules across several net- works of different species. Unlike homogeneous networks, only few research works aim at comparing heterogeneous networks. Most of the existing methods used to compare heterogeneous networks are usually manual, or use case-by-case meth- ods. In [22,19,13,16,1], authors search for a chain of reactions in a metabolic net- work, by investigating the relationships between genes involved in the reactions and the proximity of genes along the genome. Interactions between proteins that catalyze successive reactions in metabolic networks have been studied in [3,9]. In [14,8,6], authors search signaling pathways by confronting a signal transduc- tion network, represented by a directed graph, to a PPI network, represented by an undirected graph. They perform an orientation of the PPI graph as follows: given a list of ordered source-target pairs, the PPI graph is oriented in such a way that, for a maximum number of pairs (s, t), there is a directed path from the source s to the target t. The advantage of this method is that it allows to return to homogeneous networks with the same graph. However, in addition to its computational difficulty, the good behavior of this method is closely related to the choice of the list of the source-target pairs. In [8], such a list is manually constructed.
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An approximate analysis of heterogeneous and general cache networks

An approximate analysis of heterogeneous and general cache networks

Martina et al. [19] experimentally extended the results of Che et al. [4] in three directions. First, their simulations showed that the CTA can be applied to other cache replacement policies such as LRU, FIFO, RND and variants. Second their numerical results showed that the Pois- son request streams assumption at leaves can be relaxed and non-IRM models such as renewal request processes can be safely considered. Third their analysis is carried out on arbitrary hier- archical (tree) cache networks. However, their network model did not successfully address errors (e 2 ) and (e 3 ) since miss streams of requests and aggregated request processes are approximated by Poisson processes. Also, they state that a tandem of two caches “with requests flowing in the same direction” suffices to analyze general cache networks. We shall see in Section 5 that several operations such as aggregating, splitting of request streams, and also “requests flowing in opposite direction” cannot be handle or trivially derived from their tandem of two caches example. [6, 21, 10] and [3] studied TTL-based cache networks and provided exact analysis under renewal and Markov arrival request processes respectively. Under the CTA, authors of [10, 5] showed that TTL-based models can accurately describe the behavior (hit/occupancy probabilities and miss streams) of LRU, FIFO and RND caches. This claim is partially supported by recent re- sults of Melazzi et al. [20] the on performance analysis of linear LRU cache networks. Simulations in [10] showed that performance metrics at each node can be obtained with absolute relative er- rors less than 5%. Hence, by combining the CTA and TTL-based models, one can directly tackle the three sources of prediction errors (e 1 ), (e 2 ) and (e 3 ) on general and heterogeneous networks of LRU, FIFO and RND caches. However, the exact analysis carried out in [6, 21, 10, 20] is computationally expensive since it requires the evaluation of integrals/convolutions over infinite supports and/or the resolution of integral equations. This is definitely an handicap for the anal- ysis of large and arbitrary cache networks.
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Impact of Mobility on QoS in Heterogeneous Wireless Networks

Impact of Mobility on QoS in Heterogeneous Wireless Networks

Index Terms—heterogeneous networks, small cells, mobility, performance, quality of service, load and capacity analysis I. I NTRODUCTION The recent and massive commercial release of wireless network connected advanced terminals and associated applica- tions has changed users way of consuming network services. Customers did not only increase their data traffic and modify their usage, but have also increased their expectations in terms of Quality of Service (QoS) in mobility. This has led Mobile Network Operators (MNOs) to define new network planning strategies, such as the deployment of heterogeneous wireless networks. MNOs evaluate network performance by the way of QoS indicators (such as load, capacity, blocking probability), which can be derived using for example the processor sharing queue assumption with or without admission control [2]. These indicators are commonly derived in static configurations (fixed base stations and users) and temporal variations are usually introduced by the way of a user redistribution in the network following probabilistic or deterministic mobility patterns.
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Characterization of binary black holes by heterogeneous gravitational-wave networks

Characterization of binary black holes by heterogeneous gravitational-wave networks

GW151226 replica. We find that the uncertainty in the measurement of the (detector frame) chirp mass is of the order of 10 −2 M ⊙ for E 1 , L V E 1 , L V I V E 1 . The uncertainty goes down by a factor of ∼2 if a CE is added to the network, or a factor of ∼1.5 with a two-ET network. For comparison, Advanced LIGO measured the detector frame chirp mass of GW150914 with an uncertainty of 3 M ⊙ . Similar trends are present for the mass ratio, q, which can measured with uncertainties ∼6 × 10 −2 by E 1 or the heterogeneous net- works. As expected, the results from the heterogeneous networks do not significantly improve w.r.t. what one could measure with ET alone. When E 1 E 2 is used, the SNR increases, yielding an uncertainty of ∼3.6 × 10 −2 . Finally, the higher sensitivity of CE allows for uncertainties as small as ∼2.5 × 10 −2 . The numbers should be compared to the 90% credible interval of 0.34 for Advanced LIGO [55] . Figure 12 shows how the posteriors of E 1 , E 1 E 2 and L CE
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