Multiple IPv4 - IPv6 address mapping translator
(M46T)Fujitsu Limited17-25, Shinkamata 1-chome, Ota-kuTokyo144-8588Japan+81-3-3735-1111naoki.matsuhira@gmail.com
Transport Area
IPv6DraftThis document specifies Multiple IPv4 - IPv6 address mapping
Translator (M46T) specification. M46T enable access to IPv4 only host
from IPv6 host. IPv4 host is identified as M46 address in IPv6 address
space. The address assigned to IPv4 host may be global IPv4 address or
private IPv4 address. M46T does not support access to IPv6 host from
IPv4 only host.The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119.This document specifies Multiple IPv4 - IPv6 address mapping
Translator (M46T) specification. M46T enable access to IPv4 only host
from IPv6 host. IPv4 host is identified as M46 address in IPv6 address
space. The address assigned to IPv4 host may be global IPv4 address or
private IPv4 address. M46T does not support access to IPv6 host from
IPv4 only host. show M46A.M46A contain IPv4 address. Mapping IPv4 host address to IPv6
address space is already done with M46A. Address translation for IPv4
address is same as resolving M46A.IPv6 host address and corresponding IPv4 address should manage. shows translation table for
M46T. Translation table contain three value, IPv6 adddress ot IPv6
host, mapped IPv4 address for the IPv6 host, and extry expire timer
for remove the entry.In the Domain Name System, hostnames are mapped to IPv6 addresses
by AAAA resource records. M46 address can be mapped to IPv4 only host
name.In this example, M46A prefix length is 64bits, and IPv4 network
plane ID length is 32 bits. M46A prefix value is 2001:0DB8:0:46, and
IPv4 network plane ID value is 0:46.
shows these value. shows sample network
configuration. IPv6 network have 2001:0DB8:1:0/64 network prefix and
IPv4 network have 10.0.0.0/24 network prefix.IPv6 host address is 2001:0DB8:1:0::10. IPv4 only host
address is 10.0.0.10. M46 address for IPv4 only host is
2001:0DB8:0:46:0:64:10.0.0.10. FQDN of IPv4 only host is
ipv6onlyhost10.example.com. shows
DNS entry in IPv4 address space, and
shows DNS entry in IPv6 space.The address of IPv4 interface of M46T is 10.0.0.1, and the address
of IPv6 interface of M46T is 2001:0DB8:1:0::1. M46T have also IPv4
address pool for IPv6 host mapping. This example, the IPv4 address
pool is 192.168.0.0/24.The default router for IPv4 only host is M46T's IPv4 interface
address, 10.0.0.1.If using M46T in own routing domain, M46T advertise M46 address
prefix for IPv4 only host, 2001:0DB8:0:46:0:64:10.0.0.0/120.M46A prefix for route advertisement
(2001:0DB8:0:46:0:64:10.0.0.0/120)IPv4 address pool for IPv6 hostsentry expire default time (TBD)M46A contain IPv4 network plane ID, so M46T know IPv4 network
plane ID from M46A prefix.M46T examine the exists of the entry for IPv6 host, that is
source IPv6 address of IPv6 packet.If there is no entry, get IPv4 address for mapping of IPv6 host
from IPv4 address pool, and make entry to the translation
table.IF there is the entry, resove mapped IPv4 address for IPv6
host.Make IPv4 header, source address is mapped IPv4 address, and
destination address is from M46 address.Translate IPv6 packet to IPv4 packet, and send it, and reset
entry expire timer.The example addess translation table is shown in . In this example, IPv6 host
address is mapped to 192.168.0.200.Search address translation table with key destination IPv4
address, and resolve corrensponding IPv6 address.Resolve source IPv6 address from sourve IPv4 address with M46
address generation rule.Translate IPv4 packet to IPv6 packet, and sent it, and reset
extry expire timer.Remove the entry of address translation table if expire.This document may requests IANA to assign IPv6 prefix for M46 Global
address.Security consideration does not discussed in this memo, at this
time.Multiple IPv4 - IPv6 mapped IPv6 address