1,933 research outputs found
TCP in 5G mmWave Networks: Link Level Retransmissions and MP-TCP
MmWave communications, one of the cornerstones of future 5G mobile networks,
are characterized at the same time by a potential multi-gigabit capacity and by
a very dynamic channel, sensitive to blockage, wide fluctuations in the
received signal quality, and possibly also sudden link disruption. While the
performance of physical and MAC layer schemes that address these issues has
been thoroughly investigated in the literature, the complex interactions
between mmWave links and transport layer protocols such as TCP are still
relatively unexplored. This paper uses the ns-3 mmWave module, with its channel
model based on real measurements in New York City, to analyze the performance
of the Linux TCP/IP stack (i) with and without link-layer retransmissions,
showing that they are fundamental to reach a high TCP throughput on mmWave
links and (ii) with Multipath TCP (MP-TCP) over multiple LTE and mmWave links,
illustrating which are the throughput-optimal combinations of secondary paths
and congestion control algorithms in different conditions.Comment: 6 pages, 11 figures, accepted for presentation at the 2017 IEEE
Conference on Computer Communications Workshops (INFOCOM WKSHPS
Will TCP work in mmWave 5G Cellular Networks?
The vast available spectrum in the millimeter wave (mmWave) bands offers the
possibility of multi-Gbps data rates for fifth generation (5G) cellular
networks. However, mmWave capacity can be highly intermittent due to the
vulnerability of mmWave signals to blockages and delays in directional
searching. Such highly variable links present unique challenges for adaptive
control mechanisms in transport layer protocols and end-to-end applications.
This paper considers the fundamental question of whether TCP - the most widely
used transport protocol - will work in mmWave cellular systems. The paper
provides a comprehensive simulation study of TCP considering various factors
such as the congestion control algorithm, including the recently proposed TCP
BBR, edge vs. remote servers, handover and multi- connectivity, TCP packet size
and 3GPP-stack parameters. We show that the performance of TCP on mmWave links
is highly dependent on different combinations of these parameters, and identify
the open challenges in this area.Comment: 7 pages, 4 figures, 2 tables. To be published in the IEEE
Communication Magazin
Recommended from our members
A Framework for Multiaccess Support for Unreliable Internet Traffic using Multipath DCCP
Mobile nodes are typically equipped with multiple radios and can connect to multiple radio access networks (e.g. WiFi, LTE and 5G). Consequently, it is important to design mechanisms that efficiently manage multiple network interfaces for aggregating the capacity, steering of traffic flows or switching flows among multiple interfaces. While such multi-access solutions have the potential to increase the overall traffic throughput and communication reliability, the variable latencies on different access links introduce packet delay variation which has negative effect on the application quality of service and user quality of experience. In this paper, we present a new IP-compatible multipath framework for heterogeneous access networks. The framework uses Multipath Datagram Congestion Control Protocol (MP-DCCP) - a set of extensions to regular DCCP - to enable a transport connection to operate across multiple access networks, simultaneously. We present the design of the new protocol framework and show simulation and experimental testbed results that (1) demonstrate the operation of the new framework, and (2) demonstrate the ability of our solution to manage significant packet delay variation caused by the asymmetry of network paths, by applying pluggable packet scheduling or reordering algorithms
ABC: A Simple Explicit Congestion Controller for Wireless Networks
We propose Accel-Brake Control (ABC), a simple and deployable explicit
congestion control protocol for network paths with time-varying wireless links.
ABC routers mark each packet with an "accelerate" or "brake", which causes
senders to slightly increase or decrease their congestion windows. Routers use
this feedback to quickly guide senders towards a desired target rate. ABC
requires no changes to header formats or user devices, but achieves better
performance than XCP. ABC is also incrementally deployable; it operates
correctly when the bottleneck is a non-ABC router, and can coexist with non-ABC
traffic sharing the same bottleneck link. We evaluate ABC using a Wi-Fi
implementation and trace-driven emulation of cellular links. ABC achieves
30-40% higher throughput than Cubic+Codel for similar delays, and 2.2X lower
delays than BBR on a Wi-Fi path. On cellular network paths, ABC achieves 50%
higher throughput than Cubic+Codel
A novel resource scheduling algorithm to improve TCP performance for 3GPP LTE systems
The Long Term Evolution (LTE) may provide ubiquitous mobile broadband services with all IP architecture, however, the quality of service (QoS) of LTE systems is seriously affected by the network congestions, packet losses, jitters, latencies and other QoS issues in all IP networks. Thus it is valuable to investigate and design efficient resource scheduling algorithms to improve the performance of data services and end-user experiences. In this paper we propose an improved radio resource scheduling algorithm over the existing semi-continuous scheduling algorithm for the voice over Internet Protocol (VoIP) data packets. Through mapping the TCP (transmission control protocol) ACK (acknowledgement) packets into a higher priority logical channel, the probability of both the discarded ACK packets and congestions in the wireless channels are reduced. As the result, the scheme may avoid frequently opening the TCP congestion control mechanism. The simulation results have shown the advantages of our proposed algorithm, such as the RTT (Round-Trip Time) packet delay reduction, improved throughput, acceptable stability, desirable performance, and son on © 2013 IEEE
- …