Anders Andersen submitted the
>
> aspen
>
> package.
>
> Version: 1.23 2026-01-21
> License: lppl1.3c
>
> Summary description: Simple crypto notation in LaTeX
>
> Announcement text:
> ----------------------------------------------------------------------
>
> The Aspen package implements LaTeX commands closely related to what
> is often called *security protocol notation*, *standard protocol
> engineering notation*, *standard protocol notation*, or *protocol
> narrations*.
>
> The name Aspen *can* be an abbreviation for *A Security Protocol
> Engineering Notation*, but another possible abbreviation is
> *Anderson-inspired Standard Protocol Engineering Notation*, in
> memory of the late Professor Ross J. Anderson [1], who has meant
> so much for the fields of computer security, distributed systems,
> and, in particular, security engineering.
>
> Aspen is a notation for security protocols. Despite the many
> publications and textbooks found using notations for security
> protocols, the notations used are not consistent. The motivation
> for Aspen is to have an expressive and consistent notation that
> can be used in different settings where security protocols are
> presented. The Aspen package implements this notation for LaTeX.
>
> Aspen is not a formalism, like BAN (Burrows–Abadi–Needham) logic,
> or a calculus for analysis of cryptographic protocols, like Spi
> calculus. For a more detailed analysis of cryptographic protocols,
> more expressive notations like BAN logic, Spi calculus, or
> something similar should be considered. Optionally, the Aspen
> LaTeX package also implements the BAN logic notation for LaTeX.
>
> The Aspen package and its documentation are available from CTAN and
> from my private repository:
>
> -
https://www.ctan.org/tex-archive/macros/latex/contrib/aspen
> -
https://www.pg12.org/dist/texmf/tex/latex/aspen/
>
> Sincerely,
> Anders Andersen
>
> [1]
https://www.cl.cam.ac.uk/archive/rja14/
>
> ----------------------------------------------------------------------
>
> The package’s Catalogue entry can be viewed at
>
https://ctan.org/pkg/aspen
>
> The package’s files themselves can be inspected at
>
https://mirrors.ctan.org/macros/latex/contrib/aspen/
>
> ----------------------------------------------------------------------
>
> Thanks for the upload.
>
> For the CTAN Team
> Vincent Goulet
>
> ----------------------------------------------------------------------
>
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