Is NAT can provide some kind of protection?

Sun Jan 16 01:18:40 UTC 2011

On Jan 15, 2011, at 3:24 PM, Brandon Ross wrote:

> On Sat, 15 Jan 2011, Owen DeLong wrote:
> 
>> I really doubt this will be the case in IPv6.
> 
> I really hope you are right, because I don't want to see that either, however...
> 
> Why do you suppose they did that before with IPv4?  Sure you can make the argument NOW that v4 is in scarce supply, but 10 years ago it was still the case.
> 
1.	IPv4 provided no convenient way for them to dynamically assign more than a /32. DHCPv6 allows for DHCP-PD.

2.	IPv4 addresses were known to be scarce before most of the current residential ISPs even existed at least in their current form.

10 years ago, we knew that we had gone a decade beyond the point when we recognized that IPv4 would runout if we kept issuing
addresses to consumers. Frankly, we didn't, at the time, expect NAT + single address assignments to buy us more than about 10
years and it came as a bit of a surprise when we still had a bunch of space left at that point.

> Has Comcast actually come out and committed to allowing me to have as my IPs as I want on a consumer connection in the most basic, cheapest package?  Has any other major provider?
> 
No. But they have said that they are issuing prefixes and not host addresses.

I doubt any ISP will commit to offering you as many IPs as you want on the most basic consumer grade service as I don't think
any ISP would make that commitment on their top of the line business class service, either.

However, I think you will see most ISPs offering at least /56s and hopefully /48s.

Free.fr is giving out /60s, but, that's due to their limitations on their 6rd deployment and I suspect that when they
migrate to native IPv6, they may use larger prefixes.

I don't think there's too much to worry about providers handing out individual addresses in IPv6. It's too hard to maintain
and it doesn't scale like it did in IPv4.

I do think that we have to worry about things like /60s and /56s getting entrenched. I think it is unfortunate that IETF has
backed off of the /48 standard in their recent update to 3177. I think that clarification that it is for an end-site would have
been better. The use of /56s will hamper innovation and prevent vendors from bringing some cool things to the market.

Owen