An Analysis to Improve Congestion Algorithm of TCP

2010 ◽  
Vol 171-172 ◽  
pp. 756-759
Author(s):  
Kun Shang ◽  
Zhi Hua Zhai
Keyword(s):  
Congestion Control ◽  
Data Transmission ◽  
Control Algorithm ◽  
Round Trip Time ◽  
Round Trip ◽  
Trip Time ◽  
Congestion Control Algorithm ◽  
End To End

Congestion is an important issue in the research of end-to-end congestion control. The congestion issue in transmission with TCP is studied. Under the situation of different round trip time and multiple congested gateways, ECC (Explicit Congestion Control) algorithm is proposed to solve the congestion problem of TCP. The basic idea is to explicitly improve Congestion by adding mechanism at both end systems and gateways. Then study the tile congestion of Internet data transmission. Internet data transmission relies on end system mechanisms to keep Congestion. As the number of the users has been very large, this scheme has become vulnerable. It is required to deploy some congestion mechanism at gateways.

scholarly journals BBR-ACD: BBR with Advanced Congestion Detection

Electronics ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 136 ◽  
Author(s):  
Imtiaz Mahmud ◽  
Geon-Hwan Kim ◽  
Tabassum Lubna ◽  
You-Ze Cho
Keyword(s):  
Congestion Control ◽  
Network Simulator ◽  
Round Trip Time ◽  
Round Trip ◽  
Packet Losses ◽  
Recovery Mechanism ◽  
Congestion Detection ◽  
Trip Time ◽  
Drain Time ◽  
Extensive Test

With the aim of improved throughput with reduced delay, Google proposed the bottleneck bandwidth and round-trip time (BBR) congestion control algorithm in 2016. Contrasting with the traditional loss-based congestion control algorithms, it operates without bottleneck queue formation and packet losses. However, we find unexpected behaviour in BBR during testbed experiments and network simulator 3 (NS-3) simulations. We observe huge packet losses, retransmissions, and large queue formation in the bottleneck in a congested network scenario. We believe this is because of BBR’s nature of sending extra data during the bandwidth probing without considering the network conditions, and the lack of a proper recovery mechanism. In a congested network, the sent extra data creates a large queue in the bottleneck, which is sustained due to insufficient drain time. BBR lacks a proper mechanism to detect such large bottleneck queues, cannot comply with the critical congestion situation properly, and results in excessive retransmission problems. Based on these observations, we propose a derivative of BBR, called “BBR with advanced congestion detection (BBR-ACD)”, that reduces the excessive retransmissions without losing the merits. We propose a novel method to determine an actual congestion situation by considering the packet loss and delay-gradient of round-trip time, and implement a proper recovery mechanism to handle such a congestion situation. Through extensive test and NS-3 simulations, we confirmed that the proposed BBR-ACD could reduce the retransmissions by about 50% while improving the total goodput of the network.

scholarly journals Detecting and Localizing End-to-End Performance Degradation for Cellular Data Services Based on TCP Loss Ratio and Round Trip Time

2017 ◽  
Vol 25 (6) ◽  
pp. 3709-3722 ◽  
Author(s):  
Faraz Ahmed ◽  
Jeffrey Erman ◽  
Zihui Ge ◽  
Alex X. Liu ◽  
Jia Wang ◽  
...  
Keyword(s):  
Performance Degradation ◽  
Round Trip Time ◽  
Loss Ratio ◽  
Round Trip ◽  
Data Services ◽  
Trip Time ◽  
End To End

A Dynamic Approach to Estimate Receiving Bandwidth for WebRTC

2016 ◽  
Vol 7 (3) ◽  
pp. 17-33
Author(s):  
Razib Iqbal ◽  
Shervin Shirmohammadi ◽  
Rasha Atwah
Keyword(s):  
Congestion Control ◽  
Real Time ◽  
Control Mechanism ◽  
Task Force ◽  
Round Trip Time ◽  
Round Trip ◽  
Dynamic Approach ◽  
Trip Time ◽  
Proposed Model ◽  
Congestion Control Mechanism

Web Real-Time Communication (WebRTC), drafted by the World Wide Web Consortium (W3C) and Internet Engineering Task Force (IETF), enables direct browser-to-browser real-time communication. As its congestion control mechanism, WebRTC uses the Google Congestion Control (GCC) algorithm. But using GCC will limit WebRTC's performance in cases of overusing due to using a fixed decreasing factor, known as alpha (a). In this paper, the authors propose a dynamic alpha model to reduce the receiving bandwidth estimate during overuse as indicated by the overuse detector. Using their proposed model, the receiver can more efficiently estimate its receiving rate in case of overuse. They implemented their model over both unconstrained and constrained networks. Experimental results show noticeable improvements in terms of higher incoming rate, lower Round-Trip Time, and lower packet loss compared to the fixed alpha model.

scholarly journals An end-to-end flow control approach based on round trip time

2000 ◽  
Vol 23 (16) ◽  
pp. 1537-1547 ◽  
Author(s):  
Jin-Ru Chen ◽  
Yaw-Chung Chen ◽  
Chun-Liang Lee
Keyword(s):  
Flow Control ◽  
Round Trip Time ◽  
Round Trip ◽  
Control Approach ◽  
Trip Time ◽  
End To End
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