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Anomaly detection (AD) is a solution for cellular operators to overcome the difficulty of quality control over the proliferation of cellular phone usage. The telecommunications network monitoring system with anomaly detection enables immediate discovery of problems before they become more complex. Monitoring activities produce logs, which are then analyzed according to the interest, often with the help of statistics and visualizations. Relying on humans for analysis is increasingly difficult due to the immense amount of logs in modern telecommunication networks. This work extends the monitoring to automated anomaly detection by using various ELK modules to form an intelligent monitoring system. A testbed based on OpenAirInterface (OAI) and USRP B210 radiohead is used, which includes the functionalities of HSS, MME, SGW, PGW, eNB, and UE. The proposed system has an average accuracy of 91.5%. This is supported by an average value of the proportion of normal conditions that are correctly predicted at 99.31%. On the other hand, the system can still maintain the functionality of the cellular telecommunications network with an excellent predicate on service quality.

The open radio access network (RAN) aims to bring openness and intelligence to the traditional closed and proprietary RAN technology and offer flexibility, performance improvement, and cost-efficiency in the RAN’s deployment and operation. This paper provides a comprehensive survey of the Open RAN development. We briefly summarize the RAN evolution history and the state-of-the-art technologies applied to Open RAN. The Open RAN-related projects, activities, and standardization is then discussed. We then summarize the challenges and future research directions required to support the Open RAN. Finally, we discuss some solutions to tackle these issues from the open source perspective.

IoT devices are deployed in a building to instantly collect electricity load usage for next hour load consumption forecasting so that the operation of the building can be properly managed. However, due to the hardware or system error, data missing or overflow might occur. Noise might also be added into the collected data. Under this circumstance, the accuracy of next hour load forecasting would degrade which in turn decreases the building operation performance. In this paper, we propose an hourly load forecasting framework combining Data Preparation and LSTM, namely LSTM-DP, by considering data pre-processing, feature engineering and Long Short-Term Memory (LSTM). In LSTM-DP, the collected data is firstly processed by interpolation and Savitzky Golay filter, therefore the pattern of load consumption can be properly extracted by LSTM for next hour load forecasting. Moreover, we adopt two-stack LSTM to better determine the relationships among the time series information. We study the real data collected from three buildings of a company in Asia to investigate the performance of next hour load forecasting, and the results show the proposed LSTM-DP outperforms others.

A cyber-physical system (CPS) requires a time-bounded communication process for real-time interaction between the digital world and the physical world so that they can form a tight loop. Using the machine-type communication (MTC) protocol for a large-scale CPS is a good solution. However, the MTC protocol uses a random access (RA) mechanism to solve the radio resource contention problem, but that inevitably causes access delays especially in scenarios when there is a large number of MTC devices. To meet CPS requirement and address this problem, we propose a dynamic backoff window adjustment (DBA) algorithm for a pull-based RA process that can appropriately distribute the failed MTC devices engaged in the backoff window, so as to expedite their contention retrial time interval and achieve increased success probability. Simulation results showed that the DBA algorithm significantly increases the success probability of MTC devices contending for RA, and as well, shortens the mean access delay of the MTC devices. In comparison to the standard RA backoff scheme and a novel dynamic backoff (DB) scheme, the DBA algorithm proved to be more effective and suitable for the CPS to the best of our knowledge.

Multicast and broadcast service (MBS) is a point-to-multipoint service where data packets are transmitted simultaneously from a single source to multiple destinations. In MBS, some base stations (BSs) may form an MBS zone and transmit identical MBS contents simultaneously using the same modulation and coding scheme. Hence, the network has to coordinate the transmission of BSs such that BSs belonging to multiple MBS zones may utilize non-conflict resources to transmit different MBS contents. This paper extends the work in [10] for accommodating MBS zones with different service presence probabilities and various bandwidth requirements. A continuous allocation algorithm and a non-continuous allocation algorithm are presented to allocate resource units for overlapping MBS zones. Simulations were conducted to verify the effectiveness of the proposed algorithms.

Anomaly detection (AD) is a solution for cellular operators to overcome the difficulty of quality control over the proliferation of cellular phone usage. The telecommunications network monitoring system with anomaly detection enables immediate discovery of problems before they become more complex. Monitoring activities produce logs, which are then analyzed according to the interest, often with the help of statistics and visualizations. Relying on humans for analysis is increasingly difficult due to the immense amount of logs in modern telecommunication networks. This work extends the monitoring to automated anomaly detection by using various ELK modules to form an intelligent monitoring system. A testbed based on OpenAirInterface (OAI) and USRP B210 radiohead is used, which includes the functionalities of HSS, MME, SGW, PGW, eNB, and UE. The proposed system has an average accuracy of 91.5%. This is supported by an average value of the proportion of normal conditions that are correctly predicted at 99.31%. On the other hand, the system can still maintain the functionality of the cellular telecommunications network with an excellent predicate on service quality. [ABSTRACT FROM AUTHOR]

The most challenging issues in the multi-channel MAC of the IEEE 1609.4 standard is how to handle the dynamic vehicular traffic condition with a high mobility, dynamic topology, and a trajectory change. Therefore, dynamic channel coordination schemes between CCH and SCH are required to provide the proper bandwidth for CCH/SCH intervals and to improve the quality of service (QoS). In this paper, we use a Markov model to optimize the interval based on the dynamic vehicular traffic condition with high mobility nodes in the multi-channel MAC of the IEEE 1609.4 standard. We evaluate the performance of the three-dimensional Markov chain based on the Poisson distribution for the node distribution and velocity. We also evaluate the additive white Gaussian noise (AWGN) effect for the multi-channel MAC coordination scheme of the IEEE 1609.4 standard. The result of simulation proves that the performance of the dynamic channel coordination scheme is affected by the high node mobility and the AWGN. In this research, we evaluate the model analytically for the average delay on CCHs and SCHs and also the saturated throughput on SCHs. [ABSTRACT FROM AUTHOR]

Opportunity driven multiple access (ODMA), a cellular multihop method proposed for Universal Mobile Telecommunications Systems, potentially allows reduction in power consumption of user equipment (UE), extending Node B's coverage and supporting higher user data rate. However, ODMA requires extra power for discovering relaying nodes and introduces additional transmission latency in data transfer. This paper offers enlightenment to these ODMA implementation problems. A power-efficient routing (PER) mechanism is proposed to identify a minimum-power path for ODMA communication. Prior to the route (or path) discovery, the PER mechanism utilizes an analytical solution to estimate the total power and number of intermediate UEs required in the minimum-power path. With the estimation, route discovery procedures originating from nonattainable ODMA requests can be prevented. For those attainable ODMA requests that require a route discovery procedure to locate intermediate UEs, the PER mechanism further provides a method to set the transmission power and maximum hop count. Hence, the power consumption of each UE during route discovery is significantly reduced. Simulation results coincided with the analysis, and the results demonstrate the performance improvement of PER over dynamic source routing. [ABSTRACT FROM AUTHOR]

We present a traffic-scheduling framework that can dynamically allocate radio resources to a general packet radio service (GPRS) mobile station (MS) based on the interference levels of the radio links and the quality of service (QoS) specification of the MS. The underlying idea of this scheduling scheme is to preserve more bandwidth for use by those MSs that are within a low interference region so that the limited radio resources can be used more effectively. In this scheme, an MS uses a low transmission rate for data transfer when the MS is within a high interference region to avoid wasting bandwidth by transmitting data in a condition with high interference. In order to compensate for the service loss of the MS, we allocate more bandwidth to the MS when it is within a low interference region. In addition, we also propose an analytical model that can be used to derive the transmission rate for an MS in a low interference region based on the delay-bound requirement of the MS. The performance results show that our dynamic scheme can utilize the bandwidth more effectively to satisfy various QoS requirements of the MSs in the GPRS system without changing the convolution-coding rate. [ABSTRACT FROM PUBLISHER]

Provides information on the proposal of a power-spectrum-based connection admission controller design in asynchronous transfer model (ATM) switches for multimedia communications. Information on system configuration and input power-spectrum; Detailed information on power-spectrum-based connection admission control; Conclusion reached.

This work presents an improved wireless token ring protocol (IWTRP) for wireless metropolitan area networks (W-MANs) adopting a ring topology. Opposed to the single token and transmission permitted in WTRP, IWTRP provides a novel method to allow for multiple tokens, and thus multiple simultaneous transmissions in the ring. IWTRP employs both the request-to-send/clear-to-send (RTS/CTS) handshaking and the network allocation vector (NAV) updating techniques to resolve collision-resolution and token-elimination problems resulted from multiple tokens. The normalized saturation throughput of IWTRP is analytically characterized and verified through simulations. [ABSTRACT FROM PUBLISHER]

This work presents a wireless token-passing protocol, named Ripple, for wireless mesh networks (WMNs). In contrast to existing random-access approaches, Ripple uses a decentralized controlled-access approach to protect nodes from unintentional packet collisions and maximize the spatial reuse. The performance of Ripple under an error-free wireless channel was investigated and the accuracy of the analysis was verified by simulation. Simulation results also indicated that Ripple achieved throughput, stability, and QoS enhancement than that of 802.11 DCF under a highly loaded situation [ABSTRACT FROM PUBLISHER]