\chapter{\label{summary}Conclusion and Outlook}
%** Summary.tex: What have you achieved, what have you presented in this
%                document.  What are the highlights of your work.
%                It should conclude by a conclusion.

% Intro
The objective of implementing high speed NAT64 in P4 has been
achieved.

% our implementation!
Our implementation has been shown to be portable
between 2 different P4 targets and we expect it to be portable
to other P4 targets, potentially at much higher speeds.
Our in-network solution allows novel translations
without involving external routers, without involving
external routers.\footnote{Compare
  figures \ref{fig:v6v4standard} and \ref{fig:v6v4mixed}.}
We expect this to support migration to IPv6 only networks.

% P4
P4 has been proven to us as a suitable programming language for
network equipment with great potential. However in the current state
the tooling and frameworks are still immature and need significant
work to become usable for solving day-to-day challenges or supporting
large scale projects. Even with the current state drawbacks, P4 is a
very convincing language that has wide range of applications due to
its protocol independence and easy to understand architecture.
The availability of protocol independent programmable network
equipment opens up many possibilities in network
programming. While this thesis focused on NAT64, the accompanying
technology DNS64~\cite{rfc6147} could also be implemented in P4, thus
completing the translation mechanism.

% NetPFGA
In our opinion, the
P4/NetFPGA platform is a good showcase for the capabilities of
P4, demonstrating near line speed P4 programs with good capabilities
of demonstrating scientific research.
However, the supporting code toolchain shows strong weaknesses that
render productive deployments difficult.
% ----------------------------------------------------------------------
% Outlook

While the project concluded successfully, there are a variety of
possible improvements to our work as well to the used toolchains.

% Implementation
The implementation of our algorithm uses the IPv4-Compatible
IPv6 Address~\cite{rfc4291} to embed IPv4 addresses.
However RFC6052~\cite{rfc6052} defines different
embeddings depending on the prefix size. A future version should
not only support more flexible embeddings, but also consider more in
depth translation like ICMP/ICMP6 specifics.

% P4
The P4 language has shown maturity, but the usability and ease of use
of the provided toolchains can be significantly improved. Additionally,
we envision a stronger tie between the different tools in the P4
environment, like a collection of libraries and modules that could
form something on the line of a ``P4OS''. This operating system could
spawn over network switches with P4, provide a coherent library and
define data definitions that can be used in various programming
languages bindings.

% NetFPGA
The NetFPGA, from the hardware point of view, is a very
interesting hardware platform. Reducing the difficulties
we experienced with the surrounding toolchain and making
development experience more consistent has the potential to not only
make NetFPGA, but also the whole set of P4 hardware more interesting for
developers.

%% PMTU
%% handling error cases
%% No fragmentation
%% No address / mac learning
%% session handling
