RFC 4891:Using IPsec to Secure IPv6-in-IPv4 Tunnel...
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ISP


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... deployment cases, for example, an Internet Service Provider (ISP) allocating a /48 to a customer. The Customer Premises Equipment ...
... CPE) where the tunnel is terminated "trusts" (in a weak sense) the ISP's router, and the ISP ...
... ISP's router, and the ISP's router can verify that Site B is the only one that can originate packets within the /48. ...


... used to authenticate hosts or sites to an ISP using EAP methods ...


... host-to-router scenario to obtain an IPv6 address from the ISP as part of setting up the IPsec tunnel mode ...
... o Using out-of-band mechanisms, e.g., from the ISP's Web page. o Using DNS ...



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