Yeah, I guess that equation changes if you don't consider your customers
should be able to serve 'content'.
My attitude is that customers should be able to directly connect to each
other - with nothing in the middle getting in between that.
Maybe that's too idealistic in these sunset years of IPv4 allocation?
jamie
On Sun, 2009-11-01 at 19:13 +1030, Matthew Moyle-Croft wrote:SP-NAT doesn't have to scale to 300 customers per IP. Just more than1-1.One IP address may only support 4-20 customers with SP-NAT. Butthat's 4-6x what I currently get per IP. ie. take one of the /15s Iuse now for dynamic addresses - we've gone from 132k (1-1) to as manyas a few million.SP-NAT is inevitable - at some point we'll have no more IPs to haveand more customers than we have IPs requiring IPv4 connectivity.IPv6 is a way of diverting traffic away from SP-NAT and having to onlyever buy SP-NAT boxes once.MMCOn 01/11/2009, at 6:49 PM, jamie baddeley wrote:On Sun, 2009-11-01 at 15:15 +1030, Matthew Moyle-Croft wrote:On 31/10/2009, at 5:58 PM, TreeNet Admin wrote:The huge problem is all the home customers with ancientsecond-handCPE.I don't think they're a huge problem as they're the least likelytonotice the implementation of SP-NAT in front of their connection.Iknow at least one large ISP in our region considering this asphase #1of an SP-NAT implementation.I saw a great presentation at the IPv6 Hui that were held inChristchurch, Auckland and Wellington recently.It was presented by Dr Hiroshi Esaki from the WIDE project in Japan.He made it pretty clear that SP-NAT does not scale. See here:http://www.ipv6.org.nz/02C%20-%20Hiroshi%20Esaki%20keynote%20-%20IPv6%20Hui.pdfStart at Page 9 :-)The point he makes is this. TCP has a limited numberspace. Stuff ontheinternet in terms of number of connections per session can be large(andunknown frankly).iTunes has in excess of 200 connections per session. Divide 65K by200connections and you're left with an equation that says you can onlyserve iTunes to about 300 odd users from one NAT box.But you know that :-)jamieThe big issue right now is: the lack of IPv6 native support inCPE atall. If we had the larger CPE vendors starting to implement (*)thenwith a 2 year replacement time for most CPE we'd be fine by thetime alack of v4 addresses starts to pinch.In NZ at the moment with VDSL2 starting to be rolled out it'd beaPERFECT time to start squirrelling (or whatever marsuipal/mammalyouguys have) it into people's houses as people replace CPE. ButI'mguessing that it's not happening that way alas.We need to start getting IPv6 out there to end-customers to starttheball rolling to start shaking the problems down. (And believe methere a whole LOT of problems with IPv6 in actual real productiontoDSL customers ...)(*) Let's face it - given that almost all the CPE is Linux basedit'sjust laziness on the CPE vendor's part as it's already bloodywelldone for them.MMC--Matthew Moyle-CroftPeering Manager and Team Lead - Commercial and DSLAMsInternode /AgileLevel 5, 162 Grenfell Street, Adelaide, SA 5000 AustraliaEmail: mmc@internode.com.au Web: http://www.on.netDirect: +61-8-8228-2909 Mobile: +61-419-900-366Reception: +61-8-8228-2999 Fax: +61-8-8235-6909