Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Towards Flexible Anonymous Networks   Anonymous Communication designs such as Tor build their security upon
distributing the trust in many volunteers running relays in many locations
globally. These volunteers run the Tor code upon various operating systems,
each potentially having different software packaging policies. In practice, it
leads to a heterogeneous network in which many versions of the same Tor
software exist, with a different set of protocol features. Because of the
heterogeneous aspect of the network, the maintainers had to come up with
forward-compatible protocol design strategies. Their role is to guarantee that
different versions of the Tor software interact without unrecoverable errors.
In this work, we cast the protocol tolerance enabled with forward-compatible
protocol considerations as a double-edged sword. Despite being beneficial for
the developers, we argue that protocol tolerance is the systemic cause behind
many strong attacks against Tor in the past fifteen years.
  To address this issue, we propose FAN for Flexible Anonymous Network, a new
software architecture for volunteer-based distributed networks that shifts the
dependence away from protocol tolerance without losing the ability for the
developers to ensure the continuous evolution of their software. We realize an
implementation, evaluate the overheads and, experiment with several of FAN's
benefits to defend against a severe attack still applicable to Tor today.

33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom