# Information Security and Cryptography Research Group

## Augmented Secure Channels and the Goal of the TLS 1.3 Record Layer

### Christian Badertscher, Christian Matt, Ueli Maurer, Phillip Rogaway, and Björn Tackmann

The 9th International Conference on Provable Security - ProvSec 2015, LNCS, Springer, vol. 9451, pp. 85–104, Nov 2015.

Motivated by the wide adoption of authenticated encryption and TLS, we suggest a basic channel abstraction, an augmented secure channel (ASC), that allows a sender to send a receiver messages consisting of two parts, where one is privacy-protected and both are authenticity-protected. Working in the tradition of constructive cryptography, we formalize this idea and provide a construction of this kind of channel using the lower-level tool authenticated-encryption.

We look at recent proposals on TLS 1.3 and suggest that the criterion by which their security can be judged is quite simple: do they construct an ASC? Due to this precisely defined goal, we are able to give a natural construction that comes with a rigorous security proof and directly leads to a proposal on TLS 1.3 that is provably secure.

## BibTeX Citation

@misc{BMMRT15a,
author       = {Christian Badertscher and Christian Matt and Ueli Maurer and Phillip Rogaway and Björn Tackmann},
title        = {Augmented Secure Channels and the Goal of the TLS 1.3 Record Layer},
editor       = {Man Ho Au and Atsuko Miyaji},
booktitle    = {The 9th International Conference on Provable Security - ProvSec 2015},
pages        = {85--104},
series       = {LNCS},
volume       = {9451},
year         = {2015},
month        = {11},
publisher    = {Springer},
}