The following document may be of interest to Q.5

-----Original Message----- From: i-d-announce-bounces@ietf.org [mailto:i-d-announce-bounces@ietf.org] On Behalf Of Internet-Drafts@ietf.org Sent: Dienstag, 15. Februar 2005 16:32 To: i-d-announce@ietf.org Cc: iab@iab.org Subject: I-D ACTION:draft-iab-nat-traversal-considerations-00.txt

A New Internet-Draft is available from the on-line Internet-Drafts directories. This draft is a work item of the Internet Architecture Board Working Group of the IETF.

Title : Considerations for Selection of Techniques for NAT Traversal Author(s) : J. Rosenberg Filename : draft-iab-nat-traversal-considerations-00.txt Pages : 21 Date : 2005-2-14 There are many protocols designed and deployed on the Internet today which do not naturally traverse Network Address Translators (NAT). In order to allow these protocols to work in the presence of NAT, additional logic needs to be added to the network. This logic modifies the behavior of the protocol in some way. There are choices where this logic can be placed in the network. It can reside in the NATs themselves, transparently altering the protocol; when this occurs, it is called an Application Layer Gateway (ALG). It can reside in server components, hiding the changes from NATs and clients alike, it can reside in the clients, or it can reside in a combination thereof. The choice of the placement of this logic typically has implications on many aspects of the protocol, including security, deployability, manageability and availability. This document provides a set of considerations that should be taken into account by protocol and network designers when making this choice.

A URL for this Internet-Draft is: http://www.ietf.org/internet-drafts/draft-iab-nat-traversal-considerations -00.txt

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