156 research outputs found
Observing the Evolution of QUIC Implementations
The QUIC protocol combines features that were initially found inside the TCP,
TLS and HTTP/2 protocols. The IETF is currently finalising a complete
specification of this protocol. More than a dozen of independent
implementations have been developed in parallel with these standardisation
activities.
We propose and implement a QUIC test suite that interacts with public QUIC
servers to verify their conformance with key features of the IETF
specification. Our measurements, gathered over a semester, provide a unique
viewpoint on the evolution of a protocol and of its implementations. They
highlight the arrival of new features and some regressions among the different
implementations.Comment: 6 pages, 8 figure
Reducing the acknowledgement frequency in IETF QUIC
Research Funding European Space Agency University of AberdeenPeer reviewedPublisher PD
QUIC on the Highway: Evaluating Performance on High-rate Links
QUIC is a new protocol standardized in 2021 designed to improve on the widely
used TCP / TLS stack. The main goal is to speed up web traffic via HTTP, but it
is also used in other areas like tunneling. Based on UDP it offers features
like reliable in-order delivery, flow and congestion control, streambased
multiplexing, and always-on encryption using TLS 1.3. Other than with TCP, QUIC
implements all these features in user space, only requiring kernel interaction
for UDP. While running in user space provides more flexibility, it profits less
from efficiency and optimization within the kernel. Multiple implementations
exist, differing in programming language, architecture, and design choices.
This paper presents an extension to the QUIC Interop Runner, a framework for
testing interoperability of QUIC implementations. Our contribution enables
reproducible QUIC benchmarks on dedicated hardware. We provide baseline results
on 10G links, including multiple implementations, evaluate how OS features like
buffer sizes and NIC offloading impact QUIC performance, and show which data
rates can be achieved with QUIC compared to TCP. Our results show that QUIC
performance varies widely between client and server implementations from 90
Mbit/s to 4900 Mbit/s. We show that the OS generally sets the default buffer
size too small, which should be increased by at least an order of magnitude
based on our findings. Furthermore, QUIC benefits less from NIC offloading and
AES NI hardware acceleration while both features improve the goodput of TCP to
around 8000 Mbit/s. Our framework can be applied to evaluate the effects of
future improvements to the protocol or the OS.Comment: Presented at the 2023 IFIP Networking Conference (IFIP Networking
Multiple transport protocols in an adaptive RPC-based framework
The growing demand for distributed systems running in many environments and built atop heterogeneous transport protocols is apparent. However, existing middleware solutions commonly are built atop a unique protocol like TCP. This paper extends an existing framework for building middleware systems by adding several communications protocols. The proposed extensions allow developers to implement a middleware using distinct communication protocols (e.g., UDP, HTTP) or even replace them at runtime. An experimental evaluation was conducted (1) to show the impact of the new extensions on the application's performance and (2) to compare the performance of the proposed extensions with existing commercial middleware systems
Dynamical Generation of Noiseless Quantum Subsystems
We present control schemes for open quantum systems that combine decoupling
and universal control methods with coding procedures. By exploiting a general
algebraic approach, we show how appropriate encodings of quantum states result
in obtaining universal control over dynamically-generated noise-protected
subsystems with limited control resources. In particular, we provide an
efficient scheme for performing universal encoded quantum computation in a wide
class of systems subjected to linear non-Markovian quantum noise and supporting
Heisenberg-type internal Hamiltonians.Comment: 4 pages, no figures; REVTeX styl
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