NATCracker: NAT Combinations Matter

Roverso, Roberto and El-Ansary, Sameh and Haridi, Seif (2010) NATCracker: NAT Combinations Matter. In: 19th International Conference on Computer Communications and Networks, San Francisco, California, USA.

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In this paper, we report our experience in working with Network Address Translators (NATs). Traditionally, there were only 4 types of NATs. For each type, the (im)possibility of traversal is well-known. Recently, the NAT community has provided a deeper dissection of NAT behaviors resulting into at least 27 types and documented the (im)possibility of traversal for some types. There are, however, two fundamental issues that were not previously tackled by the community. First, given the more elaborate set of behaviors, it is incorrect to reason about traversing a single NAT, instead combinations must be considered and we have not found any study that comprehensively states, for every possible combination, whether direct connectivity with no relay is feasible. Such a statement is the first outcome of the paper. Second, there is a serious need for some kind of formalism to reason about NATs which is a second outcome of this paper. The results were obtained using our own scheme which is an augmentation of currently-known traversal methods. The scheme is validated by reasoning using our formalism, simulation and implementation in a real P2P network.

Item Type:Conference or Workshop Item (Paper)
ID Code:4090
Deposited By:Roberto Roverso
Deposited On:09 Feb 2011 15:26
Last Modified:27 Dec 2011 13:31

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