User Payload Research Articles

Improved Pilot Logging in DIRAC

DIRAC is a widely used framework for distributed computing. It works by building a layer between the users and the resources offering a common interface to a number of heterogeneous providers. DIRAC, like many other workload management systems, uses pilot jobs to check and configure the worker-node environment before fetching a user payload. The log messages generated by these pilot jobs are crucial for diagnosing problems in the infrastructure. In these proceedings we present a configurable, resource independent remote pilot logging system.

Near-Optimal Coding for Many-User Multiple Access Channels

This paper considers the Gaussian multiple-access channel (MAC) in the asymptotic regime where the number of users grows linearly with the code length. We propose efficient coding schemes based on random linear models with approximate message passing (AMP) decoding and derive the asymptotic error rate achieved for a given user density, user payload (in bits), and user energy. The tradeoff between energy-per-bit and achievable user density (for a fixed user payload and target error rate) is studied, and it is demonstrated that in the large system limit, a spatially coupled coding scheme with AMP decoding achieves near-optimal tradeoffs for a wide range of user densities. Furthermore, in the regime where the user payload is large, we also study the tradeoff between energy-per-bit and spectral efficiency and discuss methods to reduce decoding complexity.

An Evolving TinyML Compression Algorithm for IoT Environments Based on Data Eccentricity.

Currently, the applications of the Internet of Things (IoT) generate a large amount of sensor data at a very high pace, making it a challenge to collect and store the data. This scenario brings about the need for effective data compression algorithms to make the data manageable among tiny and battery-powered devices and, more importantly, shareable across the network. Additionally, considering that, very often, wireless communications (e.g., low-power wide-area networks) are adopted to connect field devices, user payload compression can also provide benefits derived from better spectrum usage, which in turn can result in advantages for high-density application scenarios. As a result of this increase in the number of connected devices, a new concept has emerged, called TinyML. It enables the use of machine learning on tiny, computationally restrained devices. This allows intelligent devices to analyze and interpret data locally and in real time. Therefore, this work presents a new data compression solution (algorithm) for the IoT that leverages the TinyML perspective. The new approach is called the Tiny Anomaly Compressor (TAC) and is based on data eccentricity. TAC does not require previously established mathematical models or any assumptions about the underlying data distribution. In order to test the effectiveness of the proposed solution and validate it, a comparative analysis was performed on two real-world datasets with two other algorithms from the literature (namely Swing Door Trending (SDT) and the Discrete Cosine Transform (DCT)). It was found that the TAC algorithm showed promising results, achieving a maximum compression rate of 98.33%. Additionally, it also surpassed the two other models regarding the compression error and peak signal-to-noise ratio in all cases.

Critical power analysis for control path of a CAT-M based edge device

LTE Machine Type Communication Category M1 [LTE CAT M (or M1)] is a 3GPP Low Power Wide Area Network most suitable for IoT devices that need low data rates, deep coverage, low-cost, and, most importantly, power-efficient devices. As the number of IoT system devices (called things) is growing massively, there is a shift needed from the traditional LTE network to these low power networks. Power consumption should be minimum for all stages of device functionality to keep the devices working for longest possible time. We performed a power consumption analysis of CAT-M technology under various control path scenarios using a standard CAT-M modem. Due to the absence of a live CAT-M network in India, we use a network simulator to emulate live network scenario by varying network parameters. We measured the power consumed by the CAT-M modem using a standard tool and present simulation results of a variety of network configurable parameters allowed by 3GPP. These parameters are configurable both in scope of user equipment and network deployment. This paper covers some important power measurements related to Power Saving Mode (PSM), extended Discontinuous Reception Mode (eDRX), Uplink Transmission Power, Channel Repetition, Bandwidth and Sub-carrier Spacing. Data path (user payload) considerations are not scope of this document. By the end of the paper, we identified the impact of each parameter on the performance of the CAT-M modem.

On the performance of OPC UA and MQTT for data exchange between industrial plants and cloud servers

The Internet of Things (IoT) is a key technology in the development of Industry 4.0. An increasing number of new industrial devices are expected to communicate with each other by means of local (edge) and cloud computing servers. In this article, two well-known protocols used for IoT and Industrial IoT (IIoT) are compared in terms of their performance when they are used to send/receive data to/from cloud servers. Due to their wide diffusion and suitability, the considered protocols are open platform communication-unified architecture publisher-subscriber (OPC UA PubSub) (purposely developed and maintained by industrial consortia) and message queuing telemetry transport (MQTT), the most well-known message protocol originally developed by IBM. The performance comparison is carried out considering the overall quantity of the data transferred (user payload plus overhead) and the roundtrip time required to send in data and receive a feedback message in return. The experimental results include the evaluation of several cloud computing server and application scenarios, highlighting how each protocol is particularly suitable for certain situations. Finally, conclusions about the best choice for data exchange between devices are given.

The Security model of the ALICE next generation Grid framework

JAliEn (Java-AliEn) is the ALICE next generation Grid framework which will be used for the top-level distributed computing resources management during the LHC Run 3 and onward. While preserving an interface familiar to the ALICE users, its performance and scalability are an order of magnitude better than the currently used framework. To implement the JAliEn security model, we have developed the so-called Token Certificates – short lived full Grid certificates, generated by central services automatically or on the client’s request. Token Certificates allow fine-grained control over user/client authorization, e.g. filtering out unauthorized requests based on the client’s type: end user, job agent, jobpayload. These and other parameters (like job ID) are encrypted in the token by the issuing service and cannot be altered.The client-side security implementation is further described in aspects of the interaction between user jobs and job agents. User jobs will use JAliEn tokens for authentication and authorization by the central JAliEn services. These tokens are passed from the job agent through a pipe stream, not stored on disk and thus readily available only to the intended job process. The level of isolation of user payloads is further improved by running them in containers. While JAliEn doesn't rely on X.509 proxies, the backward compatibility is kept to assure interoperability with services that require them.

The machine/job features mechanism

Within the HEPiX virtualization group and the Worldwide LHC Computing Grid’s Machine/Job Features Task Force, a mechanism has been developed which provides access to detailed information about the current host and the current job to the job itself. This allows user payloads to access meta information, independent of the current batch system or virtual machine model. The information can be accessed either locally via the filesystem on a worker node, or remotely via HTTP(S) from a webserver. This paper describes the final version of the specification from 2016 which was published as an HEP Software Foundation technical note, and the design of the implementations of this version for batch and virtual machine platforms. We discuss early experiences with these implementations and how they can be exploited by experiment frameworks.

Next Generation PanDA Pilot for ATLAS and Other Experiments

The Production and Distributed Analysis system (PanDA) has been in use in the ATLAS Experiment since 2005. It uses a sophisticated pilot system to execute submitted jobs on the worker nodes. While originally designed for ATLAS, the PanDA Pilot has recently been refactored to facilitate use outside of ATLAS. Experiments are now handled as plug-ins such that a new PanDA Pilot user only has to implement a set of prototyped methods in the plug-in classes, and provide a script that configures and runs the experiment-specific payload. We will give an overview of the Next Generation PanDA Pilot system and will present major features and recent improvements including live user payload debugging, data access via the Federated XRootD system, stage-out to alternative storage elements, support for the new ATLAS DDM system (Rucio), and an improved integration with glExec, as well as a description of the experiment-specific plug-in classes. The performance of the pilot system in processing LHC data on the OSG, LCG and Nordugrid infrastructures used by ATLAS will also be presented. We will describe plans for future development on the time scale of the next few years.

A Study of Video Transmission Performance in Bluetooth Sensor Networks Based on Slots Analysis

Based on slots consumption, the performance of video transmission in Bluetooth sensor networks was analyzed. On the premise that the maximum gross user payload data rate can satisfied the output bit rate of video source coding, the slots consumption using different packet types to transmit video stream in different SNR was analyzed, and the minimum slots consumption can be obtained by selecting the appropriate packet types to transmit video packets in different SNR, thus the Bluetooth link can vacate more slots for other business.

Multi-User Scheduling for Network Coded Two-Way Relay Channel in Cellular Systems

There has been a growing interest in analog network coding, which can improve system throughput and spectrum efficiency significantly in wireless systems. Two-way relay scenario is considered in this paper, where the base station (BS) and the relay are both equipped with multiple antennas, and each of K user equipments (UEs) in the cell has a single antenna. An advanced multi-user scheduling scheme is proposed for the analog network coded two-way relay channel, where UEs and BS exchange information via the relay node during two time slots. Because each UE with single antenna has poor transmission and reception capability, the scheduling scheme is carefully designed to decrease multi-user interference and optimize beamforming gain from BS to relay. Analytical results of sum rate and outage probability have been developed to demonstrate that the multi-user diversity gain can be achieved by the proposed scheme. Meanwhile, the user fairness of the proposed scheme is on the same order as that of round robin (RR), and the computation complexity only increases linearly with the number of users in the serving cell. Monte-Carlo simulation is conducted to exhibit the performance gains from the proposed scheduling scheme. Results show that the proposed channel correlation based user selection scheme outperforms existing traditional scheduling schemes significantly, even when the cellular user payload is low.

Weight Based Multiple Support Vector Machine Identification of Peer-to-Peer Traffic

These years, P2P applications are very popular on the Internet and take a big part of the Internet traffic workload. Identifying the P2P traffic and understanding their behavior is an important field. Previous P2P traffic identification methods by examining user payload or well-defined port numbers no longer adapt to current P2P applications. In this paper, we develop a Multi-SVM based P2P traffic identification approach by analyzing the data transmission mechanism and connection characteristics of P2P networks at the transport layer without relying on the port number and packet payload. The result shows that the approach proposed in this paper can identify P2P traffic accurately.

Bus in a new light

We describe a parallel optical link based on the Siemens' PAROLI DC chip-set-a 22-bit optical parallel bus. A companion link controller has been designed around Xilinx FPGAs, in order to transmit 32-bit data plus 4-bit flags at 40 MHz with parity check. The FPGA design handles the user payload at 40 MHz and performs segmentation and reassembly at 200 MHz. In this work, emphasis is put on the FPGA interface to the Siemens' chip-set-a design which puts to the proof the FPGA architecture. We also present POLAR (Parallel Optical Link Architecture), a VME board which implements a full duplex parallel optical link using this structure: bus in a new light.

Subsystem Impact on Space Station System Design

This article shows that space station evolutionary system designs are strongly influenced by subsystem technology. To understand this impact, the article describes an evolutionary space operations system and element interactions with mission user payloads. This description addresses what and who are involved, what are the accommodations, and when, where, and how space station facility users are accommodated. Other topics discussed include space-based orbit transfer vehicles (OTV’s), station electrical power levels, subsystem tradeoff issues and their technology development challenges, cost interactions with benefits, and payload accommodations (user-subsystem interfaces). A highlight of the discussion is the view presented of requirements for subsystem supporting technology developments.