Towards Smooth and High-Quality Bitrate Adaptation for HTTP Adaptive Streaming

Although HTTP adaptive streaming has been well documented for the cost-effective delivery of video streaming, it is still a great challenge to play back video smoothly with high quality under the fluctuating network conditions. In this paper, we proposed a novel bitrate adaptation algorithm for HTTP adaptive streaming. Our algorithm employed two approaches for throughput estimation and bitrate selection, which was evaluated on our testbed (a fully functional HTTP Live Streaming system) over a network, emulated using DummyNet. First, the throughput estimation method, based on the prediction of the difference between the estimated and instantaneous throughputs, was observed to respond smoothly to short-term fluctuations and rapidly to large fluctuations. Second, the bitrate selection algorithm, based on piecewise functions to define the variation range of the current bitrate, was found to result in smoother changes in quality with a higher average quality. The results of our experiments demonstrated the prospects of our bitrate adaptation algorithm for HTTP adaptive streaming

Analysis of Factors Affecting the String Cross-Through Capability Within Long Horizontal Section in Shale Gas Drilling

Along with the further petroleum exploration and development, the conventional oil and gas resources cannot meet the needs of rapid economic development now. Shale gas energy as an important supplement to the existing traditional energy is one of the main successive energy in the future which has very important significance for our country to realize diversified energy security strategy. In the course of drilling and developing horizontal wells in shale gas reservoirs, when it comes to hole trajectory control technology based on guide screw drill in horizontal well drilling with long horizontal section, there are some problems that string extension ability will be limited through horizontal section and low drilling efficiency will happen in later period which is not good for economic and efficient development of shale gas. This article focused on the researches of limit mechanism of the influence factors such as assembly, drill string buckling, weight on bit, well depth profile, and slope, and finally the extension ability in horizontal section was effectively improved by optimizing the well bore profile design and optimizing drilling parameters

The Design of a Dynamic Configurable Packet Parser Based on FPGA

To meet the evolving demands of programmable networks and address the limitations of traditional fixed-type protocol parsers, we propose a dynamic and configurable low-latency parser implemented on an FPGA. The architecture consists of three protocol analysis modules and a TCAM-SRAM. Latency is reduced by optimizing the state machine and parallel extraction matching. At the same time, we introduce the chain mapping idea and container concept to formulate the matching and extraction rules of table entries and enhance the extensibility of the parser. Furthermore, our system supports dynamic configuration through SDN control, allowing flexible adaptation to diverse scenarios. Our design has been verified and simulated with a cocotb-based framework. The resulting architecture is implemented on Xilinx Ultrascale+ FPGAs and supports a throughput of more than 80 Gbps, with a maximum latency of only 36 nanoseconds for L4 protocol parsing

An FPGA-Based High-Performance Stateful Packet Processing Method

Compared to a stateless data plane, a stateful data plane offloads part of state information and control logic from a controller to a data plane to reduce communication overhead and improve packet processing efficiency. However, existing methods for implementing stateful data planes face challenges, particularly maintaining state consistency during packet processing and improving throughput performance. This paper presents a high-performance, FPGA (Field Programmable Gate Array)-based stateful packet processing approach, which addresses these challenges utilizing the PHV (Packet Header Vector) dynamic scheduling technique to ensure flow state consistency. Our experiments demonstrate that the proposed method could operate at 200 MHz while adding 3–12 microseconds latency. The method we proposed also provides a considerable degree of programmability

AccelSDP: A Reconfigurable Accelerator for Software Data Plane Based on FPGA SmartNIC

Software-defined networking (SDN) has attracted much attention since it was proposed. The architecture of the SDN data plane is also evolving. To support the flexibility of the data plane, the software implementation approach is adopted. The software data plane of SDN is commonly implemented on a commercial off-the-shelf (COTS) server, executing an entire processing logic on a commodity CPU. With sharp increases in network capacity, CPU-based packet processing is overwhelmed. However, completely implementing the data plane on hardware weakens the flexibility. Therefore, hybrid implementation where a hardware device is adopted as the accelerator is proposed to balance the performance and flexibility. We propose an FPGA SmartNIC-based reconfigurable accelerator to offload some of the operation-intensive packet processing functions from the software data plane to reconfigurable hardware, thus improving the overall data plane performance while retaining flexibility. The accelerated software data plane has a powerful line-rate packet processing capability and flexible programmability at 100 Gbps and higher throughput. We offloaded a cached-rule table to the proposed accelerator and tested its performance with 100 GbE traffic. Compared with the software implementation, the evaluation result shows that the throughput can achieve a 600% improvement when processing small packets and a 100% increase in large packet processing, and the latency can be reduced by about 20× and 100×, respectively, when processing small packets and large packets

High-Performance Reconfigurable Pipeline Implementation for FPGA-Based SmartNIC

As the key module of programmable switches or the SmartNIC card, the packet processing pipeline undertakes the task of packet forwarding and processing. However, the current pipeline for the FPGA-based SmartNIC is inflexible, and the related reconfigurable commercial device designs are closed-source. To solve this problem, this paper proposes a high-performance reconfigurable pipeline design, which has fully reconfigurable match-action units, supporting various network functions by its flexible reconfiguration. The fields of the match key and the size of the match table can be reconfigured without recompiling the HDL code or modifying the hardware. The processing rules and action instructions for the pipeline can be dynamically installed by the configuration module at runtime. We implement our design on the Xilinx Alveo U200 board with a Virtex UltraScale+ XCU200-2FSGD2104E FPGA and show that the designed pipeline supports fast reconfiguration to implement new network functions and that the throughput of the designed pipeline reaches 100 Gbps with low latency

QGWFQS: A Queue-Group-Based Weight Fair Queueing Scheduler on FPGA

Weight Fair Queuing is an ideal scheduling algorithm to guarantee the bandwidth of different queues according to their configured Weights when the switching nodes of the network are congested. Many of the switching nodes based on FPGA in the current network support four physical ports or hundreds of virtual ports. Massive logic and storage resources would be consumed if each port implemented a WFQ scheduler. This paper proposes a Queue-Group-Based WFQ Scheduler (QGWFQS), which can support WFQ scheduling across multiple ports through the reuse of tag calculation and encoding circuits. We also propose a novel finish tag calculation algorithm to accommodate the variation in the link rate of each port. The remainder of integer division is also taken into account, which makes the bandwidth allocation fairer. Experimental results show that the proposed scheduler supports up to 512 ports, with 32 queues allocated on each individual port. The scheduler has the capability to operate at 200 MHz and the total scheduling capacity reaches 200 Mpps

A High-Performance and Flexible Architecture for Accelerating SDN on the MPSoC Platform

Software-defined networking has been developing in recent years and the separation of the control plane and the data plane has made networks more flexible. Due to its flexibility, the software method is used to implement the data plane. However, with increasing network speed, the CPU is becoming unable to meet the requirements of high-speed packet processing. FPGAs are usually used as dumb switches to accelerate the data plane, with all intelligence centralized in the remote controller. However, the cost of taking the intelligence out of the switch is the increased latency between the controller and the switch. Therefore, we argue that the control decisions should be made as locally as possible. In this paper, we propose a novel architecture with high performance and flexibility for accelerating SDN based on the MPSoC platform. The control plane is implemented in the on-chip CPU and the data plane is implemented in the FPGA logic. The communication between the two components is performed using Ethernet communication. We design a high-performance TCAM based on distributed RAM. The architecture employs a pipeline design with modules connected via the AXI Stream interface. The designed architecture is flexible enough to support multiple network functions while achieving high performance at 100 Gbps. As far as we know, the architecture is the first proposed in the design of a 100 Gbps system

MAToC: A Novel Match-Action Table Architecture on Corundum for 8 × 25G Networking

Packet processing offloads are increasingly needed by high-speed networks. This paper proposes a high throughput, low latency, scalable and reconfigurable Match-Action Table (MAT) architecture based on the open source FPGA-based NIC Corundum. The flexibility and capability of this scheme is demonstrated by an example implementation of IP layer forwarding offload. It makes the NIC work as a router that can forward packets for different subnet and virtual local area networks (VLAN). Experiments are performed on a Zynq MPSoC device with two QSFPs and the results show that it can work at line rate of 8 × 25 Gbps (200 Gbps), within a maximum latency of 76 nanoseconds. In addition, a high-performance MAT pipeline with full-featured, resource-efficient TCAM and a compact frame merging deparser are presented

A High-Performance and Accurate FPGA-Based Flow Monitor for 100 Gbps Networks

Network monitoring is important to improve network performance and security. The separation of the data plane and the control plane of SDN gives the network flexibility. This flexibility facilitates network management and gives rise to the need for accurate and fine-grained management of networks. However, the traditional software-based flow monitoring cannot easily keep up with today’s high-speed networks such as 100 GbE, even with the help of high-performance frameworks such as DPDK. To meet the need for fine-grained management of high-speed networks, an accurate hardware-based flow monitor design is presented in this paper. In our design, the FPGA-based pipelined cuckoo hashing is used to achieve efficient storage of flow entries. The flow information is accurately recorded without any sampling. The proposed design can achieve a higher performance than the non-sketch CPU-based methods and higher accuracy than sketch methods. Compared with other state-of-the-art flow monitors, the proposed design can achieve a performance of 100 Gbps while maintaining high accuracy