Application-layer Solutions Research Articles

ECRLoRa: LoRa Packet Recovery under Low SNR via Edge–Cloud Collaboration

Low-Power Wide-Area Networks (LPWANs), extensively utilized for connecting billions of IoT devices, encounter wireless interference challenges in unlicensed frequency bands. Cutting-edge research suggests employing Received Signal Strength Indication (RSSI) sequences for error detection to mitigate interference-related issues. Nevertheless, the effectiveness of this method significantly declines under low signal-to-noise ratios (SNRs). Additionally, long-range communication often results in low SNR received signals, sometimes even below the noise floor. Targeting this fundamental issue, this article proposes the LPWAN packet technique, broadly applicable across diverse scenarios through edge–cloud collaboration. On the edge side, we propose an innovative architecture that fully exploits spatial distribution and interference independence in the field. Rather than utilizing resource-intensive RSSI-based error detection, we leverage a lightweight coding scheme for error detection at the Long Range (LoRa) edge, forwarding correct frames to the cloud. On the cloud side, packet recovery is achieved utilizing group-weighted voting. We design and implement ECRLoRa with commercially available devices (SemTech’s SX1278 and SX1302 LoRa chipsets) and assess its performance in low SNR environments. Our thorough evaluation demonstrates that our approach attains a Packet Recovery Ratio of 96% with low SNR (i.e., below −10 dB), resulting in 1.8× throughput, 7.5× faster recovery time, and 4.92× average accuracy compared to state-of-the-art cloud-optimized application layer solutions.

On Shielding Android’s Pending Intent from Malware Apps Using a Novel Ownership-Based Authentication

PendingIntent (PI) is an authority to use the sender’s permissions and identity by the receiver. Unprotected broadcast and PI s with an empty base intent are some of the vulnerable features that a malware utilizes to perform unauthorized access and privilege escalation (PE) attacks on the PI. To protect the PI from the above attacks, this paper proposes Sticky[Formula: see text]tent, an application-layer solution that uses ownership-based authentication to dynamically control the accessibility of the PI. Sticky[Formula: see text]tent is the first holistic work to use ownership-types to protect PI s from malware attacks. Some of the existing solutions follow static analysis of binary to identify the PI vulnerability. Through our empirical study using 23,922 apps, we found [Formula: see text]17% of PI-based vulnerabilities leads to unauthorized access and privilege escalation, which can be solved by using Sticky[Formula: see text]tent. We tested our model on the state-of-art applications and found an impressive harmonic mean (F1-score) value of 0.95–0.97 for intra and inter component analysis, which is 0.4–0.18 percentage more from the existing RAICC’s (a static analysis model instrumented with IccTA/Amandroid) result. As a proof-of-concept, we have taken a few real-world PI-based applications and replaced the PI with Sticky[Formula: see text]tent library. By comparing the result with RAICC, we can see that Sticky[Formula: see text]tent performs better in protecting PI dynamically from malware access. Though the proposed solution has an overhead of 0.005% per 5[Formula: see text]min application test, the end-user suffers only negligible execution overhead in the screen response and notification delays.

Streaming High-Definition Real-Time Video to Mobile Devices with Partially Reliable Transfer

Delivering High-Definition (HD) real-time video to mobile devices is challenged with stringent constraints in delay and reliability. In the presence of network dynamics (e.g., channel errors and bandwidth fluctuations), the existing error-control mechanisms [e.g., Automatic Repeat reQuest (ARQ) and Forward Error Correction (FEC)] frequently induce deadline violations and quality degradations. To strike an effective balance between delay and reliability in real-time video transmission, this research presents an application-layer solution dubbed P artial r E liability based R eal-tim E S treaming (PERES) to perform partially reliable transfer. First, we develop an analytical framework to model the delay-constrained partial reliability for acknowledgement (ACK) and negative acknowledgement (NAK) based real-time video streaming. Second, we propose scheduling algorithms for video-aware reliability adaptation and network-adaptive buffer control. PERES is able to maximize the transmission reliability of high-priority video frames within stringent delay constraint . We implement the proposed transmission scheme in embedded video monitoring systems and evaluate the efficacy over different wireless network environments. Evaluation results demonstrate PERES achieves appreciable improvements over the reference schemes in perceptual video quality, delay performance, and bandwidth efficiency.

Buffer-Driven Rate Control and Packet Distribution for Real-Time Videos in Heterogeneous Wireless Networks

Video transmission bandwidth can be substantially increased by concurrent transmission through multiple radio interfaces introduced by heterogeneous wireless networks. However, delivering high-quality real-time videos with stringent end-to-end delay constraints is still challenging due to the time-varying multipath channel status. Thus, to integrate available multipath bandwidth and guarantee low end-to-end delay, this paper investigates a real-time concurrent multipath video transmission scheme in heterogeneous access networks. First, we present a multipath buffer analysis model (MBAM) to derive the lower and upper bounds of the target video frame bits. Second, given the low-latency and received video quality smoothness, we propose a buffer-driven rate control and packet distribution (BRCPD) algorithm aided by frame-level rate control and multipath transmission buffer awareness based on MBAM. Finally, we implement the proposed application-layer solution BRCPD algorithm in a real-world testbed. The experiment results verify that different from existing multipath video transmission schemes, the proposed algorithm is able to leverage the MBAM-based frame-level rate control to guarantee the target low end-to-end delay. In particular, the BRCPD algorithm is able to guarantee an overdue loss rate of less than 5% under strictly limited delay constraints (250 ms) in the real-world testbed.

A Study on the Method of Multi-Modem Concurrent Video Transmission in Weak-Signal and Partially-No-Signal Areas

Considering the problem that video could not be reliably transmitted in weak-signal and partially-no-signal areas just through one carrier wireless network channel for those in-field applications, a multi-modem concurrent video transmission method and system is proposed in this paper. The presented system is a pure application layer solution which mainly consists of the sending end, the receiving end, and the transmission module. The sending end realizes the dynamic load balancing according to information such as the packet loss rate from the feedback of RTCP, and the receiving end sorts and automatically reorganizes the disordered RTP packets then provides the channel evaluation information for the load balancing through the QoS corresponding to the RTCP packet transport channel and packet loss rate. Finally, test cases are designed to evaluate the performance of the proposed method. The results show that the said solution is satisfactorily capable of realizing multi-modem concurrent video transmission in weak-signal and partially-no-signal areas.

Modeling TCP Incast Issue in Data Center Networks and an Adaptive Application-Layer Solution

In data centers, the transmission control protocol (TCP) incast causes catastrophic goodput degradation to applications with a many-to-one traffic pattern. In this paper, we intend to tame incast at the receiver-side application. Towards this goal, we first develop an analytical model that formulates the incast probability as a function of connection variables and network environment settings. We combine the model with the optimization theory and derive some insights into minimizing the incast probability through tuning connection variables related to applications. Then, enlightened by the analytical results, we propose an adaptive application-layer solution to the TCP incast. The solution equally allocates advertised windows to concurrent connections, and dynamically adapts the number of concurrent connections to the varying conditions. Simulation results show that our solution consistently eludes incast and achieves high goodput in various scenarios including the ones with multiple bottleneck links and background TCP traffic.

AAIC: Adaptive-Sliding-Connection-Window Solution to TCP Incast from Application Layer

In datacenters, TCP Incast causes catastrophic goodput degradation to applications with many-to-one traffic pattern. This letter intends to tame Incast from application layer. For this goal, we first develop an analytical model to understand how to minimize Incast probability by tuning connection variables related to application. Then, enlightened by the model, we propose an adaptive application-layer solution to TCP Incast (AAIC). The solution adopts an innovative sliding-connection-window mechanism that dynamically adjusts the number of concurrent connections and the advertised window of each connection. Simulations prove the validity of our model and the effectiveness of AAIC to avert Incast in changing datacenter environments.

Predictable service overlay networks: Predictability through adaptive monitoring and efficient overlay construction and management

Providing bounded communication among participating nodes is significant for distributed systems. Internet-based applications suffer with lower performance due to absence of bounded latency. We describe PSON, an overlay network solution to this challenging problem. PSON has two components. The monitoring component, SyncProbe, utilizes efficient and adaptive monitoring techniques to measure latency, detect packet loss, and provide real-time estimates of maximum expected latency along paths of an Internet substrate. The QoSMap component constructs and manages overlay such that it yields application-level QoS and provides resilience against network failures. A distinctive feature of QoSMap is construction of QoS-compliant backup paths which facilitate in overlay management and operation during the period when primary overlay paths violate QoS. We evaluate PSON on PlanetLab to provide predictable communication for applications with different topology and QoS requirement. Our experiments confirm the effectiveness of PSON in providing an inexpensive and efficient application-layer solution to Internet’s unpredictable behavior.

A token-bucket based notification traffic control mechanism for IMS presence service

Presence is a service that allows a user to be informed about the specified state of another user. Presence service has become a key enabler for next-generation applications such as instant messaging, push-to-talk and web2.0. However, recent studies show that the notification traffic of presence service causes heavy signaling load on IP multimedia subsystem (IMS) network. This paper introduced a token-bucket based notification traffic control (TNTC) mechanism, which is an application layer solution deployed at the presence server. The TNTC aims at upgrading valid access probability while controlling the notification traffic. A mathematical model of a queuing system is proposed to describe TNTC. We analyzed its main probability features and investigated the effects of different parameters on the performance of TNTC. Extensive simulations verified that TNTC can effectively control notification traffic and perform better than the existing schemes in terms of valid access probability and update arrival rate.

CoreCast: How core/edge separation can help improving inter-domain live streaming

The rapid growth of broadband access has popularized multimedia services, which nowadays contribute to a large part of Internet traffic. Among this content, the broadcasting of live events requires streaming from a single source to a large set of users. For such content, network-layer multicast is the most efficient solution, but it has not found wide-spread adoption due to its high deployment cost. As a result, several application-layer solutions have been proposed based on large-scale P2P systems. These solutions however, are unable to provide a satisfactory quality of experience to all users, mainly because of the variability of the peers and their limited upload capacity. In this paper we advocate for a network-layer solution that circumvents the prohibitive deployment costs of previous approaches, taking advantage of the rare window of opportunity offered by the locator/identifier separation protocol (LISP). This new architecture, motivated by the alarming growth rate of the default-free zone (DFZ) routing table, is developed within the IETF, and aims to upgrade the current inter-domain routing system. We present CoreCast, an efficient inter-domain live streaming architecture operating on top of LISP. LISP involves upgrading some Internet routers and our proposal can be introduced along with these new deployments. To evaluate its feasibility in terms of processing overhead in networking equipment we have implemented CoreCast in the Linux kernel. Further, we compare the performance of CoreCast to the popular P2P streaming services both analytically and experimentally. The results show that CoreCast reduces inter-domain bandwidth consumption and that introduces negligible processing overhead in network equipment.

SIP-based mobility management in next generation networks

The ITU-T definition of next generation networks includes the ability to make use of multiple broadband transport technologies and to support generalized mobility. Next generation networks must integrate several IP-based access technologies in a seamless way. In this article, we first describe the requirements of a mobility management scheme for multimedia real-time communication services; then, we report a survey of the mobility management schemes proposed in the recent literature to perform vertical handovers between heterogeneous networks. Based on this analysis, we propose an application-layer solution for mobility management that is based on the SIP protocol and satisfies the most important requirements for a proper implementation of vertical handovers. We also implemented our proposed solution, testing it in the field, and proving its overall feasibility and its interoperability with different terminals and SIP servers.

Cross-Layer Packetization and Retransmission Strategies for Delay-Sensitive Wireless Multimedia Transmission

Existing wireless networks provide dynamically varying resources with only limited support for the quality of service required by the bandwidth-intense, loss-tolerant and delay-sensitive multimedia applications. This variability of resources does not significantly impact delay insensitive data transmission (e.g., file transfers), but has considerable consequences for multimedia applications. Recently, the research focus has been to adapt existing algorithms and protocols at the lower layers of the protocol stack to better support multimedia transmission applications and conversely, to modify application layer solutions to cope with the varying wireless networks resources. In this paper, we show that significant improvements in wireless multimedia performance can be obtained by deploying a joint application-layer adaptive packetization and prioritized scheduling and MAC-layer retransmission strategy. We deploy a state-of-the-art wavelet coder for the compression of the video data that enables on-the-fly adaptation to changing channel conditions and inherent prioritization of the video bitstream. We pose the cross-layer problem as a distortion minimization given delay constraints and derive analytical solutions by modifying existing joint source-channel coding theory aimed at fulfilling rate, rather than delay, constraints. We also propose real-time algorithms that explicitly consider the available information about previously transmitted packets. The obtained results show significant improvements in terms of video quality as opposed to ad-hoc optimizations currently deployed, while the complexity associated with performing this optimization in real time, i.e., at transmission time, is limited

Global internet roaming with ROAMIP

Reachability and session continuity represent two distinct services that global mobility protocols should provide. Reachability is the possibility for Internet hosts to initiate sessions to mobile users. Session continuity refers to mechanisms that ensure that active transport or application layer sessions are not broken due to mobility. We present ROAMIP, a global mobility architecture that uses application layer solutions for global reachability and reuses transparent Mobile IP tunnelling mechanisms to ensure session continuity. ROAMIP eliminates long triangular routes, yet it is compatible with mobility unaware correspondent hosts. It is applicable to IPv6 as well as IPv4 networks. The ROAMIP architecture naturally lends itself to easy, gradual deployment and can reuse existing Mobile IP or SIP message formats. We conclude the paper by showing example traces from an experimental implementation.