Softwire Concentrator Discovery Using DHCP

Document Type Expired Internet-Draft (individual)
Authors Dayong Guo  , Sheng Jiang  , Brian Carpenter 
Last updated 2010-07-12
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


Several types of Carrier Grade NATs have been proposed to simplify IPv4/IPv6 transition of the edge network by integrating tunnels and NAT. A very common scenario is that many users set up softwires to a softwire concentrator for public or private access services. In order to establish softwires successfully, a new mechanism is required to enable users in the edge network to discover the information of the concentrator. This document describes how a host or Customer Premises Equipment discovers the remote softwire concentrator or CGN in a hub and spoke network using DHCP. Based on two new Softwire Concentrator Discovery DHCP Options, proposed in the document, a user can obtain the information of the softwire concentrator or CGN and then set up a tunnel to it.


Dayong Guo (
Sheng Jiang (
Brian Carpenter (

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)