[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [RRG] Consensus? IPv4 scaling problem must be solved directly, not by relying on migration to IPv6
In my opinion, we don't necessarily have to solve the IPv4 situation.
A reasonable (which is not the same as "ideal") scenario would be that
IPv4 is largely frozen the way it is at a certain point in time and
IPv4 will continue to be the place where all servers are available,
while (new) clients are attached to the IPv6 network. Client-server
protocols are very easy to translate when the clients are on IPv6 and
the servers on IPv4, the only issue is with peer-to-peer protocols
that require each peer to be reachable for every other peer.
On 26 mei 2008, at 6:53, Robin Whittle wrote:
I think that networked games are a big enough category of protocol
to present a serious barrier for the widespread marketability of an
I'm not all that interested in counting users, so my question is: how
many games use peer-to-peer protocols? The ones that I'm familiar with
(from about a decade ago) are all straightforward UDP client-server
protocols, which will easily survive translation if the clients are
able to communicate over IPv6 and there are no referrals. Also, the
number of servers is very limited, so upgrading them to dual stack
doesn't seem like much of an issue.
Initially, why should all these game developers add messy proxy
stuff and IPv6 capabilities to their already immensely complex
programs, just to suit a handful of people who have chosen to pay
for a different kind of Internet service than what the rest of the
This is exactly the reason IPv6 has seen so little uptake so far. Then
again, we still have a billion unused IPv4 addresses. It's no use
complaining that nobody buys umbrellas when the sun is shining.
I think it is likely that in order for the system to work, all
participants in these multi-player games would need upgraded
software - probably the entire protocol would need to change so it
could be amenable to proxying to some host which doesn't have an
So? AFAIK, these online games cost something like $10 a month. As soon
as the number of users that only have decent connectivity over IPv6
rises to even a few percent it's worthwhile to make these updates.
You haven't addressed my argument that there is great scope for the
next decade or so making better use of IPv4 space, especially with
map-encap - and that this will be cheaper and better than trying to
get end-users to pay for a second-rate IPv6-only Internet service.
Toothpaste doctrine: at some point it starts becoming annoying to
squeeze harder and harder, you just buy a new tube. IPv4 address
management is already quite expensive today and that's only going to
get worse. Obviously a lot depends on how many addresses you need. If
you start with 256 and you need a million, that's a lot worse than if
you have a million and you need 256.
You are proposing that all these protocols be made amenable to
proxying - and that some good souls would promptly write, test and
deploy the relevant proxying code for all the ISPs who sell IPv6
This does not seem all realistic to me.
This was done to support NAT, too. The only problem here is the early
adopter issue: it's hard to be the first when there are no products,
vendors won't build something until there is a market. But those
cycles can be broken.
% VoIP protocols - standard and proprietary.
Again, a small minority of Internet users, and might
well work fine without any change.
A small minority???
Absolutely. I moved to another country, have to pay insane amounts to
call my family on my cell phone because they can't be bothered to
Hopefully someone else can contribute to this discussion - I think
your assessments are not realistic.
It looks like ICE, the mechanism that makes SIP work through NAT, can
survive IPv4-IPv6 translation with only minor changes if the
translator behaves in a certain way.
... and various IM programs, VoIP etc.
Instant messaging is largely client-server. I've been able to use
Google Talk Jabber through a translator without any problems. File
transfers don't work, but they usually don't on IPv4, either (for me).
A very small number of residential users have deployed some sort
of peer-to-peer system.
I don't believe it is a "very small number".
BitTorrent will use IPv6 if/when available and discovers IPv6 peers
using a dynamic hash table even if the tracker won't accept IPv6 or
FQDN referrals. (Which was originally part of the protocol but
optimized away in later changes.) In BitTorrent-like peer-to-peer
applications you also don't need each peer to be able to talk to every
other peer, just as long as there are a few that are double stack it
How do you use an application which is only written for IPv4 (as
many are) on an IPv6-only host?
First you translate to IPv6, then back to IPv4 again. :-)
s/other end-users/desirable services/
What's all this slash stuff?
This is how you do search and replace in the vi editor.
This is the key point. For an IPv6-only client to be happy, the
services (s)he wishes to reach must be accessible via IPv6.
That is a vastly easier and more realistic goal than Robin
describes. It even has a built-in economic incentive, since
the service providers want clients*.
But why would service providers go to a lot of trouble to make their
sites available to an initially small number of people who chose to
pay for a Internet service which is technically totally different
from what the rest of the world uses?
Because we're running out of IPv4 addresses.
Or because once you get everything on IPv6, you don't have to deal
with any problems caused by NATs and filters in ISPs. IPv6 is the
ultimate NAT traversal system. If I were building a corporate network
from scratch I'd run all the internal stuff IPv6-only with translation
at the edge. This may have some initial challenges, but it's much more
future proof than messing with IPv4.
Why would those users adopt such a service before a very large
proportion of other end-users (including content providers) support
their kind of service?
IPv6 has had 10 years to be adopted - and virtually no-one has
IPv6 is the second most successful layer 3 protocol in history. There
was a time when I joked that more people run CLNP (in order to use the
IS-IS routing protocol) than IPv6, but I don't think that's the case
anymore. Nearly every time a Mac user configures their Apple wifi base
station this happens over IPv6.
* This argument applies to peer-to-peer services too. It slightly
increases the desirable properties of a supernode - the ideal
supernode will not only be outside firewalls and NATs, but will
also be dual stacked.
I don't clearly understand this.
I understand, but disagree. Supernodes aren't necessarily proxies.
to unsubscribe send a message to email@example.com with the
word 'unsubscribe' in a single line as the message text body.
archive: <http://psg.com/lists/rrg/> & ftp://psg.com/pub/lists/rrg