Hasan Erkan

On the Vision of Complete Fixed-Mobile Convergence

This paper reviews and outlines the key features of the emerging next-generation fixed passive optical network (NG-PON)-based and fourth-generation (4G) mobile broadband access technologies and how to leverage the advantages of both of these access technologies to build a next-generation hybrid fiber-wireless (FiWi) network. Specifically, this paper presents an overview of the most recent research activities on these hybrid FiWi architectures, aiming to clarify the basic differences and distinguish between two FiWi networking architectural models, namely, the overlay or independent model and the truly integrated model. We then explore and present a new direction to the design and implementation of a simple and cost-effective all-packet-based converged fixed-mobile access networking solution that enables the true integration of NG-PON and 4G mobile broadband access technologies into the envisioned fixed-mobile platform. We briefly outline the general and technical requirements to support a unified NG-PON long-term evolution (LTE) radio access network (RAN) architecture that conforms to both the typically centralized fixed PON and the emerging distributed 4G mobile LTE access standards. The implementation methodology on how to efficiently and cost-effectively integrate these two access technologies along with the main advantages gained from such an integrated architecture are outlined and presented.

A Novel Ring-Based WDM-PON Access Architecture for the Efficient Utilization of Network Resources

This work proposes a simple and cost effective local access WDM-PON architecture that combines the salient features of both traditional static WDM-PON (i.e., dedicated connectivity to all subscribers with bit rate and protocol transparencies, guaranteed QoS, and increased security) and dynamic WDM-PON (i.e., efficiently utilizing network resources via dynamic wavelength allocation/sharing among end-users). Specifically, this paper proposes and devises a novel ring-based local access WDM-PON architecture that efficiently supports dynamic allocation of wavelengths/timeslots and sharing traffic as well as a truly shared LAN capability among PON end-users.

Native Ethernet-Based Self-Healing WDM-PON Local Access Ring Architecture: A New Direction for Supporting Simple and Efficient Resilience Capabilities

This paper proposes and devises a simple and cost-effective native Ethernet-based self-healing WDM-PON access ring architecture for next-generation broadband access. Specifically, this paper proposes and devises simple, efficient, and cost-effective fully distributed fault detection and recovery schemes for the proposed WDM-PON ring architecture. The main characteristics of the proposed architecture is that it supports a fully distributed control plane among the ONUs, which enables each and every ONU to independently detect, manage, and recover most of the networking failure scenarios.

Dynamic and fair resource allocation in a distributed ring-based WDM-PON architectures

Abstract The overall objective of this paper is to propose and devise a dynamic and fair resource allocation technique in a ring-based WDM-PON architecture with truly shared LAN capabilities among end-users. A new distributed control plane is developed for this architecture that enables intercommunication among the ONUs, as well as signaling and scheduling procedures that operate in a distributed manner. To cope with the unpredictable users’ behavior and bandwidth demands, which shift both in time and place in such a networking environment, supported by the devised control plane, a distributed and efficient network resource allocation and sharing strategy is developed allowing for efficient dynamic allocation and sharing of overall downstream, upstream, and LAN network resources by adaptively adjusting them to the offered load. Performance results concerning link throughput and delay are presented, validating that the proposed methodology can meet the capacity requirements of the dynamic and highly fluctuant traffic pattern of the emerging multimedia applications and services. Specifically, the simulation results clearly show the effectiveness of the proposed shared wavelength strategy as the downstream/upstream network throughput is almost equal to the ideal theoretical throughput.

Design and performance of hybrid FSO/RF architecture for next-generation broadband wireless access networks

This paper proposes a novel Ethernet-based wired/wireless broadband access networking architecture that utilizes the existing wired trunk feeder fiber of typical PON infrastructure along with a hybrid FSO/RF reliable wireless connectivity to the end-users. By combining the benefits of both FSO and RF technologies, the proposed integrated networking solution can provide a downstream bandwidth of up to 2.5 Gbps per wavelength and 99.999% availability at a range of 1 km in all weather conditions [2]. All the previous work on hybrid FSO/RF was based on point to point, our proposed architecture is unique in the sense of providing point to multipoint access to end users and bringing all wired/wireless network in to single network, which is transparent to the users.

Reliability considerations of the emerging PON-based 4G mobile backhaul RAN architecture

This work proposes a fully distributed protection mechanism for a ring-based wavelength-division-multiplexed passive optical network (PON) broadband access architecture that can be utilized as an all-packet-based converged fixed-mobile access networking transport infrastructure for backhauling mobile traffic. Such an architecture will enable the true integration of PON-based and fourth-generation mobile broadband access technologies into the envisioned fixed-mobile platform. Specifically, this paper proposes two different fault detection and recovery schemes, namely, fully distributed and hybrid (distributed/centralized). In this ring-based architecture, each optical network unit can independently detect, manage, and recover most of the networking failure scenarios. The proposed protection schemes are capable of protecting against both node and distribution/trunk fiber failures and enable the recovery of all network traffic including upstream, downstream, and LAN data. In addition, these schemes can also protect against any combination of concurrent double failures including trunk/distribution fiber breaks and node failures. The hybrid architecture delivers these efficient resilience capabilities and incurs almost no additional power loss compared to that of the normal working architecture.

Survivable broadband local access PON architecture: a new direction for supporting simple and efficient resilience capabilities

This work proposes a two-fiber self-healing ring-based local access passive optical network (PON) architecture that addresses some of the limitations of current tree-based PON architectures including supporting private networking capability as well as providing simple and cost-effective fully distributed resilience capabilities against most kinds of networking failures. Specifically, this work proposes and devises a simple self-healing Ethernet PON architecture that supports a truly shared LAN capability among end users. The main characteristic of the proposed architecture is that it supports a fully distributed control plane among the optical network units (ONUs) for ONU-to-ONU communication. The control plane supports fully distributed fault detection and recovery mechanisms as well as a decentralized dynamic bandwidth allocation scheme in which the optical line terminator is excluded from both the bandwidth arbitration and fault detection and recovery processes. The proposed decentralized automatic protection switching technique is capable of protecting against both node (ONU) and fiber failures (distribution and trunk) through active participation of ONUs. This scheme enables the recovery of all network traffic including upstream, downstream, and LAN data. In addition, the proposed protection technique can protect against any combination of concurrent double failures including trunk and distribution fiber breaks and node failures.

A novel ring-based EPON architecture

Ethernet passive optical network (EPON) has drawn considerable research attention in recent years. EPON can be implemented in different topologies in access network environment. Recently, the tree topology was the focus of the researchers. In this paper, we propose a cost effective novel ring-based EPON architecture with associated dynamic bandwidth allocation (DBA) algorithm as an alternative to standard EPON architectures. This architecture, compared with conventional ring, allows optical line terminal (OLT) receiver to function with narrower dynamic range through minimization of near-far problem. In addition, the proposed DBA algorithm outperforms other DBA algorithms proposed in the literature. This proposed architecture is proved to be fault-tolerant and cost effective. Furthermore, this novel approach also has the potential of inter-optical network units (ONU) connectivity, which can bring LAN support in access environment

Downstream bandwidth allocation scheme in local access over a distributed control plane

This work analyzes the downstream impediments of centralized local access networks with LAN capability and proposes an efficient downstream scheme over a distributed upstream control plane, where OLT is relieved from the burden of upstream control function and inter-ONU communication.