Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An Analysis of the Skype Peer-to-Peer Internet Telephony Protocol   Skype is a peer-to-peer VoIP client developed by KaZaa in 2003. Skype claims
that it can work almost seamlessly across NATs and firewalls and has better
voice quality than the MSN and Yahoo IM applications. It encrypts calls
end-to-end, and stores user information in a decentralized fashion. Skype also
supports instant messaging and conferencing. This report analyzes key Skype
functions such as login, NAT and firewall traversal, call establishment, media
transfer, codecs, and conferencing under three different network setups.
Analysis is performed by careful study of Skype network traffic.

18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
24
The categories of this paper are: dg-ga
13
The categories of this paper are: quant-ph
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
2
The categories of this paper are: math
6
The categories of this paper are: astro-ph
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th