Ruziev Ulugbek Shukhrat Ugli, Seok-Yoon Kim, Youngmo Kim, Sun-Jib Kim
In OTT (Over-The-Top) service environments, reliable recording and verification of content usage history are becoming increasingly important for copyright protection, royalty settlement, and dispute resolution. However, conventional platform-specific log management methods have limitations in interoperability, integrity assurance, and external verifiability. In addition, simple indicators such as the number of views or total playback time are insufficient to accurately reflect actual OTT viewing behavior, which often includes nonlinear interactions such as pause, seek, replay, and early stop. This paper proposes a platform-independent event-based verification method for OTT content usage history. The proposed method defines usage history metadata consisting of content information, session information, playback event information, and usage result information, and derives valid usage intervals from playback events such as play, pause, seek, replay, and stop. In addition, hash-based verification information and linked recording structures are applied to the generated usage history to enhance integrity and traceability. To examine the applicability of the proposed method, processing latency in the usage history aggregation stage was measured according to changes in the number of sessions and platforms. The experimental results show that the processing time increased in a stable manner as the session scale increased, indicating that the proposed method can be applied to large-scale OTT usage environments. This study is meaningful in that it presents a platform-independent and verifiable method for organizing OTT content usage history, and it can be further extended through future performance evaluation of blockchain recording and verification processes in diverse service environments.
Centralized cloud storage, computing, and processing can not fulfill the quality of service (QoS), e.g., high bandwidth and low latency, at reduced costs to emerging applications, such as virtual reality, smart transportation, etc. This paper proposes a hybrid computing framework that can use the best of cloud, fog, and edge capabilities and can be tailored to the needs of applications. Note that fog and edge computing infrastructures, designed for proximity to users, have emerged as promising complements to traditional cloud computing. While fiber access networks can offer QoS to end users connected over fixed devices, an integrated fiber-wireless access network can fulfill mobile end-users requirements. Our framework integrates artificial intelligence techniques for resource optimization, control, and monitoring, among other tasks. Furthermore, we envision that edge devices and sensors, together with fog and cloud, can utilize a distributed ledger technology, such as Blockchain, to establish a trust-based relationship. Finally, we present a use case of hybrid computing over a distributed fiber-wireless network enabled by AI and Blockchain. We show that hybrid computing is essential in balancing a tradeoff between communication latency to generate alert signals and minimizing the power consumption of a system.
Yuancheng Cai, Shitong Xiang, Min Zhu, Wei Luo · 12 authors
This Letter demonstrates a novel, to the best of knowledge, overlapping single-sideband (OSSB) transmission scheme for spectrally efficient multi-service fiber-wireless (FiWi) access in a low-cost direct-detection (DD) THz system. Utilizing the proposed OSSB scheme, user data from different services can share the same spectrum resource yet can be successfully demodulated via one cost-effective DD THz receiver in conjunction with the Kramers-Kronig (KK) based SSB field reconstruction and look-up table (LUT) enabled signal separation algorithms. A proof-of-principle experiment is conducted. Based on an IQ modulator and a single THz zero-bias diode (ZBD), two independent 10-GBd quadrature phase shift keying (QPSK) signals with an overlapped spectrum are successfully demodulated after 20-km fiber and up to 3-m wireless transmission at the 300-GHz band. To the best of our knowledge, this is the first demonstration of multi-service FiWi access with an OSSB format in a 300-GHz DD THz system.
An Elastic Optical Network (EON) nowadays usually accommodates multiple Virtual Optical Networks (VON) by allocating orthogonal spectrum resources for them. A fixed resource allocation pattern may result in a low quality of service since data traffic on VONs may fluctuate with time. Spectrum trading (ST) among VONs could solve this problem by moving spectrum resources between them and blockchain-based ST has recently gained much interest since it avoids the traditional centralization concern. In this paper, we propose a smart contract based decentralized ST scheme for VONs. The system is built on a private blockchain which can be implemented with the off-shelf Ethereum platform at a low development cost. A frequency slot (FS) trading contract (FSTC) is designed to trade unoccupied spectrum resources among VONs. Compared with existing schemes, FSTC explicitly addresses the virtual link brokerage (VLB) problem by trading in the granularity of virtual links. Furthermore, FSTC ensures FS information authenticity and enables FS recyclability via mechanisms based on Ethereum smart contract features. We implement FSTC with Solidity and evaluate its costs which demonstrate the feasibility of the proposed solution.
We propose LightHash , the first feasible photonic cryptographic hash function for blockchain technology using programmable photonic networks. We experimentally evaluate LightHash and assess whether photonic circuits can outperform digital competitors in latency and energy efficiency.
Jingchi Li, Shaohua An, Honglin Ji, Xingfeng Li · 6 authors
For high-capacity and short-reach applications, carrier-assisted differential detection (CADD) has been proposed, in which the optical field of a complex-valued double sideband (DSB) signal is reconstructed without using a sharp-edge optical bandpass filter or local oscillator laser. The CADD receiver features a transfer function with periodical nulls in the frequency domain, while the signal-signal beat interference (SSBI) is severely amplified around the frequency nulls of the transfer function. Since the null magnitude at the zero frequency is inevitable, a guard band is required between the carrier and the signal, leading to a higher receiver bandwidth and implementation cost. To reduce the needed guard band, we propose a parallel dual delay-based CADD (PDD-CADD), in which an additional delay is placed parallel to the original delay in the conventional CADD. By this means, the modified transfer function has a sharper roll-off edge around the zero frequency. Consequently, the requirement on the guard band can be relaxed, which maximizes the bandwidth utilization of the system. The parallel delay is first optimized through numerical simulation. We then perform a proof-of-concept experiment to transmit a 100-Gb/s orthogonal frequency division multiplexing (OFDM) 16-ary quadrature amplitude modulation (16-QAM) signal over an 80-km single-mode fiber (SMF). After the fiber transmission, the proposed PDD-CADD can reduce the required guard band from 3 to about 1.2 GHz compared with the single delay-based conventional CADD. To our best knowledge, for the direct detection of a single polarization complex-valued DSB signal without using a sharp-roll-off optical filter, we achieve a record electrical spectral efficiency of 5.9 b/s/Hz.
TeraFlow proposes a new type of secure, cloud-native Software Defined Networking (SDN) controller that will radically advance the state-of-the-art in beyond 5G networks by introducing novel micro-services architecture, and provide revolutionary features for both flow management (service layer) and optical/microwave network equipment integration (infras-tructure layer) by adapting new data models. TeraFlow will also incorporate security using Machine Learning (ML) and forensic evidence for multi-tenancy based on Distributed Ledgers. Finally, this new SDN controller shall be able to integrate with the current Network Function Virtualization (NFV) and Multi-access Edge Computing (MEC) frameworks as well as to other networks. The target pool of TeraFlow stakeholders expands beyond the traditional telecom operators towards edge and hyperscale cloud providers.
Shifeng Ding, Gangxiang Shen, Kevin X. Pan, Sanjay K. Bose · 6 authors
In communication networks, network virtualization can usually provide better capacity utilization and quality of service (QoS) than what can be achieved otherwise. Under this operation, once the capacity of a virtual optical network (VON) is allocated, it will be static for a certain period, for example, a service contract period. However, in reality, the actual traffic demand of a VON always fluctuates, which would lead to a mismatch between the capacity assigned and the actual traffic demand carried. This mismatch would further cause degradation of provisioned network services and inefficiency in assigned network capacity. To overcome this issue, we propose a new scheme, called spectrum trading (ST), to trade spectrum resources between VONs in the context of an elastic optical network (EON). The key idea is to allow different VONs to trade their spectrum resources according to their actual capacity requirement at different time instants. A VON with unused spectra can trade away its unused spectra to other VONs that are short of spectrum resources at that time. in exchange, it is rewarded with some credit for its contribution to the ST community, which it can then use later to obtain extra capacity, if needed. The trust-worthiness of the trading records between the VONs is ensured in a distributed fashion through a blockchain- assisted ledger that is updated whenever a new trade occurs. A software-defined control plane is also developed to enable spectrum trading with the support of the blockchain-assisted ledger. The performance of the ST scheme is evaluated and compared with the scenario without such trading. Results show that the proposed ST scheme is efficient in improving the QoS of each VON and significantly improves overall network capacity utilization.
This paper presents a blockchain-based high-efficiency security strategy with blockchain ledger-based recovery algorithm for software-defined optical networks. Numerical results show the proposed strategy has less recovery latency and superior network performances.
We first present a blockchain-based trusted cloud radio over optical fiber network architecture (BlockONet) with anonymous access identification for future 5G fronthaul. The feasibility and efficiency of the architecture are experimentally verified on our testbed.
Suhaidi Hassan, Yousef Fazea, Adib Habbal, Huda Ibrahim
The blockchain is a distributed ledger shared among computers around the world that allowing anyone to transact and do business with each other. Once a new block is created, ledger's transactions are updated and synchronized. Hence, the speed of information propagation in order to minimize the time taken by a node to verify a block before announcing it to the network is very significant that should be leveraged by the enabling technologies. However, due to the huge of data capacity needed, mode division multiplexing (MDM) is a promising approach to provide an additional level of freedom through propagating different channels in multimode fiber (MMF). Nevertheless, mode coupling is considered as the primary bandwidth impairment of MMF due to the mode's random perturbation. This paper investigates the potential of mode spacing in conjunction with a feed-forward equalizer on twisted Laguerre-Gaussian (LG) MDM. Free error transmission of 40Gbit/s over MMF is achieved. The bit-error-rate and eye diagram have been used as a measurement metrics.
Cloud radio access network (C-RAN) interconnects thousands of terminal devices to support the services of Internet of Things (IoT) in 5G area. However, centralized access authentication of each terminal has been performed in mobile core network which causes an extremely high operating and capital expenditure of network. Traditional C-RAN cannot provide an authentic mechanism to guarantee the security of services and creditability of device and resource accessing with low network cost. We first propose a blockchain-based trusted authentication (BTA) architecture for 5G with blockchain-based anonymous access (BAA) scheme in cloud radio over fiber network. The feasibility and efficiency are verified on enhanced SDN testbed to enable blockchain as a service.
An ultra-long distance distributed intrusion detecting system assisted with power amplification and sensitivity enhancement is proposed and demonstrated. First, through introducing multiple bidirectional amplifiers into the unbalanced Mach-Zehnder/Sagnac interferometer-based fiber sensing link, the sensing distance is remarkably extended, and second, the signal-to-noise ratio of this sensing system is significantly improved from less than 2 to 6-8 dB by coating the sensing fiber with organic silicone polymer. Furthermore, the high-order downtrend fitting function is adopted to implement the intrusion locating of ultralong distance sensing; the zero-padding fast Fourier transform algorithm and multiple-averaging method are jointly utilized for the improvement of the locating accuracy. Experimentally, a proof-of-concept distributed intrusion detecting system is constructed with the employment of bidirectional amplification. In particular, the ultra-long sensing distance up to 226.337 km is implemented, which is the reported longest distributed sensing system to the best of our knowledge.