Ipv4 Over Ipv4 Tunnel - 3Com MSR 50 Series Configuration Manual

IPv4 over IPv4 Tunnel

Figure 206 Principle of 6to4 tunnel and 6to4 relay
6to4 router
6to4 network
Site 1
Router A
4 ISATAP tunnel
With the application of the IPv6 technology, there will be more and more IPv6
hosts in the existing IPv4 network. The ISATAP tunneling technology provides a
satisfactory solution for IPv6 application. An ISATAP tunnel is a point-to-point
automatic tunnel. The destination of a tunnel can automatically be acquired from
the embedded IPv4 address in the destination address of an IPv6 packet. When an
ISATAP tunnel is used, the destination address of an IPv6 packet and the IPv6
address of a tunnel interface both adopt special addresses: ISATAP addresses. The
ISATAP address format is prefix(64bit):0:5EFE:ip-address. The ip-address is in the
form of a.b.c.d or abcd:efgh, where abcd:efgh represents a 32-bit source IPv4
address. Through the embedded IPv4 address, an ISATAP tunnel can automatically
be created to transfer IPv6 packets. The ISATAP tunnel is mainly used for
connections between IPv6 routers or between a host and an IPv6 router in the IPv4
network.
Figure 207 Principle of ISATAP tunnel
IPv 6 network
IPv 6 host
5 GRE tunnel
IPv6 packets can be carried over GRE tunnels to pass through the IPv4 network by
using standard GRE protocol to encapsulate them. Like the IPv6 manually
configured tunnel, a GRE tunnel is a point-to-point link, too. Each link is a separate
tunnel. The GRE tunnel is mainly used for stable connections requiring regular
secure communication between border routers or between a host and a border
router. For related configurations, refer to
Introduction to IPv4 over IPv4 tunneling protocol
IPv4 over IPv4 tunneling protocol (RFC1853) is developed for IP data packet
encapsulation so that data can be transferred from one IPv4 network to another
IPv4 network.
IPv4 network
IPv 4 network
ISATAP tunnel
ISATAP router
"GRE Configuration" on page
Introduction to Tunneling
6to4 router
6to4 network
Site 2
Router B
6to4 relay
IPv6 network
Site 3
Router C
IPv 4 address :
2 . 1 . 1 . 1 / 24
IPv 6 address :
FE 80 :: 5 EFE : 0201 : 0101
3 FFE :: 5 EFE : 0201 : 0101
IPv 4 / IPv 6 host
1589.
697