As you Asking for the Difference Between the Teredo And ISATAP the Differnce is given below

6to4 is a mechanism where a router with a public IPv4 address can be an IPv6 gateway/provider for a whole set of LANs

The IPv6 prefix starts with 2002: followed by the 32 bits of the public IPv4 address. This gives a /48 prefix which can be used to provide 65536 LANs with a /64 each.

the Difference Between the Teredo And ISATAP is given below

Introduction

Teredo is a built-in mechanism in Windows systems that is used to give a single system behind an IPv4 NAT access to IPv6. Like 6to4 it uses public relays

Whereas
the ISATAP is a managed technology for providing IPv6 on an IPv4 network. It emulates IPv6 connectivity on the IPv4 infrastructure. IPv6 Router Discovery usually uses multicast.


Working

. Teredo combines this with a setup protocol using Teredo servers (by default those hosted by Microsoft) to detect and break through the IPv4 NAT


ISATAP solves that in a different way. An ISATAP router is provided on the network and its IPv4 address is made known to the ISATAP hosts (usually using the hostname isatap. in DNS). The ISATAP hosts then can use that address to set up their IPv6 connectivity.