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zombie_2112
@intevaproducts.com

zombie_2112

Anon

[ipv6] route from v4 to v6?

This might be a dumb question, but is it possible to route, to have a router, whether hardware or software, that routes from V4 to V6? And back?

Can't you encapsulate v4 packets in v6?

Curious, thanks.

NetDog
Premium Member
join:2002-03-04
Hollywood, FL

NetDog

Premium Member

Re: [ipv6] route from v4 to v6?

Yes, you can tunnel v4 over v6 or v6 over v4. But a v4 packet can't talk to a v6 packet, or a v4 only system cant talk to a v6 only system.

Think of it like this, if you have a English speaking person talking to a Spanish speaking person. One of them need to speak the other person's language, that would be dual-stack in this case.
quesix
join:2005-12-19
Cary, IL
ARRIS SB6141
Cisco 2851
Asus RT-AC66

1 recommendation

quesix to zombie_2112

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If you are looking for technical answer, yes, as netdog said Wikipedia has list of these different encapsulations, which of course need to be De-encapsulated as well:
»en.wikipedia.org/wiki/IP ··· chanisms

Otherwise it may to helpful to learn more about what you are trying to accomplish and what you have to work with? most commonly someone wants to get on IPv6 internet as client or server before ISP and/or hardware can support it, in which case if it's the ISP you may want to signup for a service like he.net's tunnel broker at »ipv6.he.net which uses 6in4. (tip: many newer routers can support this directly in the router GUI/web interface, if using a real CISCO router in the CLI)

One common misconception is that all ISPs have to do is an a router or server so that clients can talk to IPv6 internet, this is not the case. The encapsulation are used for TEMPORARY fix to get IPv4 network segments on IPv6 internet, and for TUNNELS/BRIDGES between islands of IPv6 (or IPv4 in the coming years, as IPv6 takes over as primary, or for private networks).

IPv6 only connections are unlikely to occur for another 6-10 years. Instead IPv4 will move to CGN carrier grade NAT to continue providing IPv4 access, so your bilingual English/Spanish hardware and software will not need any special treatment to continue talking to IPv4 internet. When it does start you won't be able to access non-upgraded systems, unless they are your own or a friend's endpoints and you setup a TUNNEL/BRIDGE using a variation of 4in6 protocol (most of the protocols on Wikipedia above are variations of 6in4)

p.s. yes i know i got a bit wordy... was trying to cover all bases... given limited data on what you are looking for)

NetDog
Premium Member
join:2002-03-04
Hollywood, FL

NetDog

Premium Member

said by quesix:

p.s. yes i know i got a bit wordy... was trying to cover all bases...

Wordy at times is good, alot of people give me a hard time that I dont give out more details or "wordy"..
HELLFIRE
MVM
join:2009-11-25

HELLFIRE to zombie_2112

MVM

to zombie_2112
Short answer : yes

Long answer : as the other posters have said, but with the caveat of "why would you want to" and "what are you trying to do."

@quesix : good article all-around, thx for the link

Regards

rchandra
Stargate Universe fan
Premium Member
join:2000-11-09
14225-2105

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to zombie_2112
You might also want to look at NAT64 and DNS64. Basically, it's meant as a way to have IPv6 clients interact with IPv4 servers.
quesix
join:2005-12-19
Cary, IL
ARRIS SB6141
Cisco 2851
Asus RT-AC66

quesix to zombie_2112

Member

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NAT64 is very limited, i think best summary is that it is used to allow IPv6 clients to connect to an IPv4 server, or two specific IPv4 hosts to talk to each other over IPv6 internet (by using NAT64 at both ends). Note: NAT64 is not run on the client but on router in front of IPv4 LAN/server. The packets are not "encapsulated" but headers are converted.

rchandra
Stargate Universe fan
Premium Member
join:2000-11-09
14225-2105
ARRIS ONT1000GJ4
EnGenius EAP1250

rchandra

Premium Member

Here's the "Readers' Digest" version of it:

An edge system (e.g., router) connects to the IPv4 and IPv6 Internet, as well as the presumably IPv6 only LAN. A part of the local address space is allocated to NAT64. All clients (on the LAN) must query this LAN's DNS64 server; if they don't, this won't work. The DNS64 server will look up AAAA records on behalf of LAN clients (recursive queries), but if it only finds A records, it synthesizes a(n) AAAA response which should direct the traffic to the NAT64 address, whilst encoding the IPv4 address within that address. I'm not sure what the DNS64 server will do with A queries, whether it would turn them into AAAA queries or not (presumably yes on an IPv6 LAN, as IPv4 wouldn't be useful). When the (LAN) client begins transmitting packets, they wouel go to the NAT64 system. The NAT64 system realizes the destination is in the local NAT64 address range, and extracts the IPv4 address encoded within the DNS64 synthesized address. Mostly, the NAT64 system needs to remove the IPv6-specific parts, mainly the IPv6 addresses (leaving just the TCP, UDP, or whatever layer), and inserts its own IPv4 address for the source address and the extracted address for the IPv4 destination address, and transmits the packet (over IPv4). Anything coming in the reverse direction gets its IPv4 stuff such as addresses removed and the NAT64 addressing bolted back on.

Depending on implementation, this NAT could be stateful (as most IPv4 NATs are today) or stateless.