NEC NEAX IPS NWA-008869-001, Installation Manual

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CHAPTER 1 GENERAL INFORMATION
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NWA-008869-001 Rev.1.0
atch1001.fm
IPv6/IPv4 Tunneling
Tunneling is the function that the information of a protocol is encapsulated into the packet of an another
protocol and transferred. Tunneling makes it possible to transfer data between networks having different
protocols. A maximum of eight tunnels are available, of which one is an automatic tunnel, and reserved.
Many of the present networks are created with IPv4 and, therefore, IPv6 networks will be separated by
IPv4 networks. If you want to shift to an IPv6 network in a stepwise manner, you can set a tunnel for the
communication between hosts.
An In-Skin Router encapsulates an IPv6 packet into a IPv4 datagram to send the encapsulated packet over
the IPv4 network. Upon receiving the encapsulated packet, another In-Skin Router extracts the IPv6 packet
from the IPv4 packet and sends it to an IPv6 host.
By using an existing IPv4 network, you can shift smoothly to an IPv6 network.
IPv6 over IPv4
IPv6 Host
IPv6 network
IPv4 network IPv6 network
IPv6 Host
IPv6 packet IPv6 packet IPv4 packet
Tunneling
Encapsulation
In-Skin Router
2000 IPS 2000 IPS
Packet extraction
In-Skin Router
SYSTEM OUTLINE