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Title: Sidecar: in-network performance enhancements in the age of paranoid transport protocols
In response to ossification and privacy concerns, post-TCP transport protocols such as QUIC are designed to be “paranoid”—opaque to meddling middleboxes by encrypting and authenticating the header and payload—making it impossible for Performance-Enhancing Proxies (PEPs) to provide the same assistance as before. We propose a research agenda towards an alternate approach to PEPs, creating a sidecar protocol that is loosely-coupled to the unchanged and opaque, underlying transport protocol. The key technical challenge to sidecar protocols is how to usefully refer to the packets of the underlying connection without ossification. We have made progress on this problem by creating a tool we call a quACK (quick ACK), a concise representation of a multiset of numbers that can be used to efficiently decode the randomly-encrypted packet contents a sidecar has received. We implement the quACK and discuss how to achieve several applications with this approach: alternate congestion control, ACK reduction, and PEP-to-PEP retransmission across a lossy subpath.  more » « less
Award ID(s):
2045714 2039070 2028733 1909212 1763256
PAR ID:
10424939
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
The Twenty-first ACM Workshop on Hot Topics in Networks (HotNets 2022)
Page Range / eLocation ID:
221 to 227
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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