In this paper, we propose a novel multichannel network with infrastructure support, which is called an MC-IS network, that has not been studied in the literature. To the best of our knowledge, we are the first to study such an MC-IS network. Our proposed MC-IS network has a number of advantages over three existing conventional networks: a single-channel wireless ad hoc network (called an SC-AH network), a multichannel wireless ad hoc network (called an MC-AH network), and a single-channel network with infrastructure support (called an SC-IS network). In particular, the network capacity of our proposed MC-IS network is @math times higher than that of an SC-AH network and an MC-AH network and the same as that of an SC-IS network, where @math is the number of nodes in the network. The average delay of our MC-IS network is @math times lower than that of an SC-AH network and an MC-AH network and @math times lower than the average delay of an SC-IS network, where @math and @math denote the number of channels dedicated for infrastructure communications and the number of interfaces mounted at each infrastructure node, respectively. Our analysis on an MC-IS network equipped with omnidirectional antennas has been extended to an MC-IS network equipped with directional antennas only, which are named as an MC-IS-DA network. We show that an MC-IS-DA network has an even lower delay of @math compared with an SC-IS network and our MC-IS network. For example, when @math and @math , an MC-IS-DA can further reduce the delay by 24 times lower than that of an MC-IS network and by 288 times lower than that of an SC-IS network.
The fourth network related to our network is a multi-channel wireless mesh network with infrastructure support (called an network) @cite_50 @cite_32 @cite_37 @cite_26 @cite_12 @cite_5 , which is the evolution of multi-channel multi-interface wireless mesh networks (called an network) @cite_7 @cite_27 . An network is different from our network due to the following characteristics of an network: [(i)] a typical network consists of mesh clients , mesh routers and mesh gateways while an network consists of common nodes and infrastructure nodes. [(ii)] different types of communications exist in the multi-tier hierarchical network, which are far more complicated than an network. For example, there are communications between mesh clients, communications between mesh gateways, and communications between a mesh gateway and a mesh router. [(iii)] an network uses wireless links to connect the backbone networks (corresponding to the infrastructure network in an network). As a result, the assumption of the unlimited capacity and the interference-free infrastructure communications in an network does not hold for an network. [(iv)] the traffic source of an network is either from a mesh client or from the Internet while the traffic always originates from the same network in an network.
@cite_37 @cite_26 @cite_7 @cite_32 @cite_27 @cite_50 @cite_5 @cite_12
2054952342 2135861020 1662911496 1980168610
Research into the analytical solutions for the capacity of the infrastructure wireless mesh networks (InfWMN) is highly interesting. An InfWMN is a hierarchical network consisting of mesh clients, mesh routers and gateways. The mesh routers form a wireless mesh infrastructure to which the mesh clients are connected through the use of star topology. The previous analytical solutions have only investigated the asymptotic per-client throughput capacity of either single-channel InfWMNs or multi-channel InfWMNs under conditions in which each infrastructure node (i.e. wireless routers and gateways), has a dedicated interface per-channel. The results of previous analytical studies show that there are quite few studies that have addressed the more practical cases where the number of interfaces per-node is less than the number of channels. In this paper, we derive an original analysis of the asymptotic per-client throughput capacity of multi-channel InfWMNs in which the number of interfaces per-infrastructure node, denoted by m, is less than or equal to the number of channels, denoted by c. Our analysis reveals that the asymptotic per-client throughput capacity of multi-channel InfWMNs has different bounds, which depend on the ratio between c and m. In addition, in the case that m < c, there is a reduction in the capacity of the InfWMN compared to the case in which c = m. Our analytical solutions also prove that when ( c m = ( N _g^2 N _ r ) ), where Ng and Nr denote the number of gateways and mesh routers respectively, gateways cannot effectively increase the throughput capacity of the multi-channel InfWMNs. The capacity problem in wireless mesh networks can be alleviated by equipping the mesh routers with multiple radios tuned to non-overlapping channels. However, channel assignment presents a challenge because co-located wireless networks are likely to be tuned to the same channels. The resulting increase in interference can adversely affect performance. This paper presents an interference-aware channel assignment algorithm and protocol for multi-radio wireless mesh networks that address this interference problem. The proposed solution intelligently assigns channels to radios to minimize interference within the mesh network and between the mesh network and co-located wireless networks. It utilizes a novel interference estimation technique implemented at each mesh router. An extension to the conflict graph model, the multi-radio conflict graph, is used to model the interference between the routers. We demonstrate our solution’s practicality through the evaluation of a prototype implementation in a IEEE 802.11 testbed. We also report on an extensive evaluation via simulations. In a sample multi-radio scenario, our solution yields performance gains in excess of 40 compared to a static assignment of channels. Even though multiple non-overlapped channels exist in the 2.4 GHz and 5 GHz spectrum, most IEEE 802.11-based multi-hop ad hoc networks today use only a single channel. As a result, these networks rarely can fully exploit the aggregate bandwidth available in the radio spectrum provisioned by the standards. This prevents them from being used as an ISP's wireless last-mile access network or as a wireless enterprise backbone network. In this paper, we propose a multi-channel wireless mesh network (WMN) architecture (called Hyacinth) that equips each mesh network node with multiple 802.11 network interface cards (NICs). The central design issues of this multi-channel WMN architecture are channel assignment and routing. We show that intelligent channel assignment is critical to Hyacinth's performance, present distributed algorithms that utilize only local traffic load information to dynamically assign channels and to route packets, and compare their performance against a centralized algorithm that performs the same functions. Through an extensive simulation study, we show that even with just 2 NICs on each node, it is possible to improve the network throughput by a factor of 6 to 7 when compared with the conventional single-channel ad hoc network architecture. We also describe and evaluate a 9-node Hyacinth prototype that Is built using commodity PCs each equipped with two 802.11a NICs. This paper studies the asymptotic throughput capacity of a random infrastructure wireless mesh network (RndInfWMN). Generally an infrastructure wireless mesh network (InfWMN) comprises mesh clients, routers, gateways and has hierarchical structures. An InfWMN can be divided into two categories, which are arbitrary InfWMN (ArbInfWMN) and random InfWMN (RndInfWMN). In an ArbInfWMN, the locations of the WMRs are arbitrary while in an RndInfWMN, WMRs are distributed randomly. The latter is more interesting when randomly distributed WLANs are desired to be connected through a wired network of gateways. There are some analytical research on the asymptotic capacity of ArbInfWMN where the number of interfaces per-infrastructure node, m, is at the same order of the number of available channels for the network, c, i.e. cm=@q(1). In our previous research, we investigated the asymptotic throughput capacity of ArbInfWMNs for a more general case in which cm=O(1). However, to date, analytical facility has been limited by the absence of analysis in RndInfWMNs, especially for the general case in which cm=O(1). In this paper, we carry out an original analysis of the asymptotic per-client throughput capacity of multi-channel multi-interface RndInfWMNs for the case in which cm=O(1). Our analysis shows that by identifying cm in different scaling regimes, the asymptotic per-client throughput capacity of multi-channel multi-interface RndInfWMNs exhibits different bounds, depending on the ratio between c and m.