Design and Service Provisioning Methods for Optical Networks in 5G and Beyond Scenarios

Network operators are deploying 5G while also considering the evolution towards 6G. They consider different enablers and address various challenges. One trend in the 5G deployment is network densification, i.e., deploying many small cell sites close to the users, which need a well-designed transport network (TN). The choice of the TN technology and the location for processing the 5G protocol stack functions are critical to contain capital and operational expenditures. Furthermore, it is crucial to ensure the resiliency of the TN infrastructure in case of a failure in nodes and/or links while the resource efficiency is maximized.Operators are also interested in 5G networks with flexibility and scalability features. In this context, one main question is where to deploy network functions so that the connectivity and compute resources are utilized efficiently while meeting strict service latency and availability requirements. Off-loading compute resources to large and central data centers (DCs) has some advantages, i.e., better utilization of compute resources at a lower cost. A backup path can be added to address service availability requirements when using compute off-loading strategies. This might impact the service blocking ratio and limit operators’ profit. The importance of this trade-off becomes more critical with the emergence of new 6G verticals.This thesis proposes novel methods to address the issues outlined above. To address the challenge of cost-efficient TN deployment, the thesis introduces a framework to study the total cost of ownership (TCO), latency, and reliability performance of a set of TN architectures for high-layer and low-layer functional split options. The architectural options are fiber- or microwave-based. To address the strict availability requirement, the thesis proposes a resource-efficient protection strategy against single node/link failure of the midhaul segment. The method selects primary and backup DCs for each aggregation node (i.e., nodes to which cell sites are connected) while maximizing the sharing of backup resources. Finally, to address the challenge of resource efficiency while provisioning services, the thesis proposes a backup-enhanced compute off-loading strategy (i.e., resource-efficient provisioning (REP)). REP selects a DC, a connectivity path, and (optionally) a backup path for each service request with the aim of minimizing resource usage while the service latency and availability requirements are met.Our results of the techno-economic assessment of the TN options reveal that, in some cases, microwave can be a good substitute for fiber technology. Several factors, including the geo-type, functional split option, and the cost of fiber trenching and microwave equipment, influence the effectiveness of the microwave. The considered architectures show similar latency and reliability performance and meet the 5G service requirements. The thesis also shows that a protection strategy based on shared connectivity and compute resources can lead to significant cost savings compared to benchmarks based on dedicated backup resources. Finally, the thesis shows that the proposed backup-enhanced compute off-loading strategy offers advantages in service blocking ratio and profit gain compared to a conventional off-loading approach that does not add a backup path. Benefits are even more evident considering next-generation services, e.g., expected on the market in 3 to 5 years, as the demand for services with stringent latency and availability will increase

NOVEL ANALYTICAL APPROACHES IN THE DETERMINATION OF EMERGING CONTAMINANTS

Ph.DDOCTOR OF PHILOSOPH

End-to-End Provisioning of Latency and Availability Constrained 5G Services

We address a key challenge of 5G networks by proposing a strategy for the resource-efficient and end-to-end allocation of compute and connectivity resources in a dynamic 5G service provisioning scenario, such that the service latency and availability requirements are guaranteed. Our heuristic algorithm shows that resource efficiency is significantly improved by processing services in the large core data centers (DCs) with a rich amount of compute resources and exploiting the benefits of traffic grooming over the metro and core fiber links. Moreover, our resource-efficient provisioning algorithm avoids possible violation of the service availability requirements caused by reaching the central DC locations by adding backup connectivity resources. Our simulation results demonstrate a resource efficiency improvement reflected by lowering the service blocking probability by up to four orders of magnitude compared to the conventional service provisioning methods utilizing distributed small DCs

A Shared-Path Shared-Compute Planning Strategy for a Resilient Hybrid C-RAN

One key challenge in 5G networks is to guarantee the survivability of services in the event of failures. This paper focuses on the hybrid cloud radio access network (H-CRAN) architecture. The proposed strategy guarantees survivability in the presence of failures affecting nodes/links in the midhaul segment (i.e., connecting the radio aggregation unit (RAU) nodes to their respective radio cloud center (RCC) nodes) as well as compute resources (i.e., servers) in the RCC nodes. In the envisioned strategy each RAU node is connected to a primary and a backup RCC node (i.e., with backup compute resources) via two node disjoint connectivity paths in the midhaul. The proposed strategy, called Shared-Path Shared-Compute Planning (SPSCP), lowers the overall design cost by trying to share as much as possible backup connectivity and compute resources among RAU nodes. This is made possible by introducing a shareability metric early into the RCC node selection process so that the chance of sharing backup resources is maximized. Simulation results show that the SPSCP strategy can lead to up to 28% cost savings when compared to conventional resilient design strategie

Fiber- vs. Microwave-based 5G Transport: a Total Cost of Ownership Analysis

Answering a key question from operators, the paper compares the techno-economic performance of fiber and microwave-based 5G transport deployments using vendor’s inventories and real-life field deployment scenarios. Results highlight how microwave gains vary based on the geo-types, the fiber trenching, and microwave equipment costs

Techno-economics of Fiber vs. Microwave for Mobile Transport Network Deployments [Invited]

One of the challenges for network operators is to design and deploy cost-efficient transport networks (TNs) to meet the high capacity and strict latency/reliability requirements of today’s emerging services. Therefore, they need to consider different aspects, including the appropriate technology, the level of reconfigurability, and the functional split option. A crucial aspect of network design is assessing the impact of these aspects against the total cost of ownership (TCO), latency, and reliability performance of a given solution. For this reason, this paper proposes a framework to investigate the TCO, latency, and reliability performance of a set of fiber and microwave-based TN architectures. They are categorized based on their baseband functional split option and the reconfigurability capabilities of the equipment used. The results, based on real data from a non-incumbent operator, show that in most of the considered scenarios, a microwavebased TN exhibits lower TCO than a fiber-based one. The TCO gain may vary with the choice of the functional split option, geo-type, reconfigurability features, fiber trenching costs, and cost of microwave equipment, with a more significant impact in a dense urban geo-type, where for a low layer functional split option the fiber- and microwave-based architectures have a comparable TCO. Finally, it was found that the considered fiber and microwave architectures have almost similar average latency and connection availability performance. Both are suitable to meet the service requirements of 5G and beyond 5G services in most of the considered scenarios. Only in extreme latency-critical scenarios, a small number of the cells might not fully satisfy the latency requirements of a low layer split option due to multiple microwave hops in the microwave-based architecture

Techno-economics of 5G transport deployments

Network densification is a crucial enabler for 5G, requiring the installation of a large number of devices and/or cables for the 5G transport network. This invited paper provides a techno-economic study focusing on adopting microwave and fiber equipment for 5G transport network deployments. Different architectures for low layer split supporting latency critical services are considered

Cost Benefits of Centralizing Service Processing in 5G Network Infrastructures

We assess the benefits of centralizing service processing in a few high-scale data center locations within an operator infrastructure. Results show up to 74% less cost while provisioning latency and availability constrained services

Survey of the association between polymorphisms of CTLA-4 exon 1 49 A/G genes with rheumatoid arthritis in Iran

Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), which suppresses T cell proliferation, is a promising candidate for the susceptibility genes to rheumatic arthritis diseases (RA). This study aims to examine the association between the polymorphisms of the CTLA-4 exon 1(+ 49) genes with RA in the Qazvin city of Iran population. The polymerase chain reaction of genomic DNArestriction fragment length polymorphism (PCR-RFLP) was applied to genotype the CTLA-4 exon 1(+ 49) polymorphisms in 105 RA patients and 90 control subjects. Laboratory diagnostic tests were also measured for RA and control groups. Our results did not demonstrate a significant difference in allele and genotype frequencies of the CTLA-4 exon 1(+ 49) between RA patients and the control group (p < .0001). There was no significant difference in age at onset, CRP, RF value in patients with RA according to the CTLA-4 polymorphisms; just anti-CCP showed a significant difference. Our data declared that polymorphisms of CTLA-4 exon 1(+ 49) genes are not correlated with RA susceptibility and its clinical and paraclinical manifestations