This article provides an up-to-date survey of hybrid fiber-wireless (FiWi) access networks that leverage on the respective strengths of optical and wireless. A definitive objective of Fiber-Wireless (FiWi) systems is the meeting of different optical and wireless innovations under a solitary base keeping in mind the end. Survey Smoothly Fiber-Wireless (FiWi) Accessing Wireless Networks: Convergence and Challenges. Naseer Hwaidi Alkhazaali, Raed Abduljabbar Aljiznawi.
|Published (Last):||6 April 2010|
|PDF File Size:||8.66 Mb|
|ePub File Size:||1.33 Mb|
|Price:||Free* [*Free Regsitration Required]|
Given the location of the wireless mesh routers, the optimal placement of ONUs was found with the objective to nstworks the total number of required wireless hops. LagkasPanagiotis G. However, these data packets may arrive at the OLT out of order due to the fact that each path in general has a different delay.
Clearly, to exploit the benefits of steering peer-to-peer traffic along wireless-optical-wireless paths, the placement of ONUs has a great impact on the achievable throughput of FiWi networks. To calculate the minimum delay path for upstream data transmissions from wireless mesh clients to the OLT, a gateway takes the current load of its collocated ONU into account and estimates the upstream delay on the EPON. RoF networks are attractive since they provide transparency against modulation techniques and are able to support various digital formats and wireless standards in a cost-effective manner.
The power utilities are responsible for the installation of the network infrastructure as well as its operation and maintenance but leave its access open to all e. In addition, it enables the convergence of the optical fiber infrastructure with standard wireless solutions, thus offering a way to integrate dominant wired and wireless technologies in a hybrid access network supporting seamless ubiquitous broadband services.
The explosion of mobile data traffic has mandated the need for a new cellular architecture. In addition, DARA performs admission control, where a packet is admitted into the wireless mesh only if the predicted delay along the computed path is below a predetermined threshold.
Fiber-Wireless (FiWi) Broadband Access Networks in an Age of Convergence: Past, Present, and Future
References Publications referenced by this paper. In the WMN, skrvey certain percentage of the link capacity is allocated to each traffic class access every mesh node and either traffic class is allowed to exceed its allocated bandwidth only if the other traffic class has not reached its maximum bandwidth. Specifically, in CaDAR, each node informs its neighboring nodes about the current traffic load of all its outgoing links via periodic LSA messages. Based on this information, data packets are routed along the lowest residual capacity path between each pair of source and destination nodes.
According to the Federal Communications Commission FCCbroadband enables individuals and enterprises to access a wide range of resources, services, and products related to education, culture, entertainment, telemedicine, e-commerce, public safety, accesx homeland security. Furthermore, it was shown that the above-described bandwidth allocation schemes help decrease the packet acccess and increase the per-flow throughput of the network.
The inter-ONU traffic from all ONUs is combined into one fiber by means of a passive combiner, which is attached to one of two input ports of an arrayed-waveguide grating AWG. Citations Publications citing this paper. The second proposed heuristic optimizes the placement of ONUs by means of simulated annealinga widely used combinatorial optimization technique.
Future broadband access networks not only have to provide access to information when we need it, where we need it, and in whatever format we need it, but also, and arguably more importantly, have to bridge the digital divide and offer simplicity and user-friendliness based on open standards in order to stimulate the design of new applications and services.
In the former case, the throughput of FiWi networks is limited by the bandwidth bottleneck and interferences of communications in the wireless subnetwork.
Advances in Optics
OW communications links operate at much higher carrier frequencies than their RF counterparts. It was shown by means of q that in terms of both average delay and packet loss RADAR clearly outperforms minimum hop, shortest path, and predictive throughput routing algorithms for a wide range of failure scenarios such as gateway, ONU, and OLT failures.
In a wireless front-end with multiple-radio mesh nodes, it is important to assign the wireless channels efficiently such that contention is reduced. After an ONU is deregistered, the incoming traffic to that ONU is temporarily stored at the network terminal until the reregistration is achieved.
Flows are optimally assigned among the different paths with the objective to minimize the out-of-order probability beyond the OLT subject to given packet delay requirements. Also note that the capacity of the PON is much higher than that of the wireless front-end such that peer-to-peer traffic can be easily carried in the optical backhaul without suffering from any serious throughput penalty.
However, with increasing peer-to-peer traffic the interferences in the wireless accwss front-end increase and the throughput of WMNs decreases dramatically. This not only provides more time for professional and personal activities for corporate and our own personal benefit but also helps reduce fuel consumption and protect the environment; issues that are becoming increasingly important in our lives.
Multihop relaying is used to extend the range. MuralidharanWeichao WangAlexander M. This trend is syrvey to become even more pronounced over the next couple of decades. The resultant peer-to-peer traffic can be routed either through the multihop wireless path within the wireless subnetwork or through the wireless-optical-wireless fiber-wwireless, whereby traffic is first sent from mesh client via its associated mesh router to its closest ONU 1 and is then forwarded upstream to the OLT.
In [ 4748 ], a new routing algorithm, called capacity and delay aware routing CaDARwas proposed with the fiber-woreless to distribute sruvey radio capacity of a single-radio wireless mesh network node optimally among its outgoing links such that the average delay is minimized.
More interestingly, to better comprehend the true potential of the aforementioned emerging trends, it is helpful to put them into a wider nontechnical context and see how they fit into the avcess picture of present and past economic recessions.