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Comment: Dual Homing Failover and IPv6 address aggregation (Score 1) 380

by billstewart (#49543191) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

Yeah, that turned out to be one of the big problems with IPv6 address aggregation - sounds great in the ivory tower, doesn't meet the needs of real customers, which is too bad, because every company that wants their own AS and routable address block is demanding a resource from every backbone router in the world.

IPv6's solution to the problem was to allow interfaces to have multiple IPv6 addresses, so you'd have advertise address 2001:AAAA:xyzw:: on Carrier A and 2001:BBBB:abcd:: on Carrier B, both of which can reach your premises routers and firewalls, and if a backhoe or router failure takes out your access to Carrier A, people can still reach your Carrier B address. Except, well, your DNS server needs to update pretty much instantly, and browsers often cache DNS results for a day or more, so half your users won't be able to reach your website, and address aggregation means that you didn't get your own BGP AS to announce route changes with, but hey, your outgoing traffic will still be fine.

My back-of-a-napkin solution to this a few years ago was that there's an obvious business model for a few ISP to conspire to jointly provide dual-homing. For instance, if you've got up to 256 carriers, 00 through FF, each pair aa and bb can use BGP to advertise a block 2222:aabb:/32 to the world, and have customer 2222:aabb:xyzw::/48, so the global BGP tables get 32K routes for the pairs of ISPs, and each pair of ISPs shares another up-to-64K routes with each other using either iBGP or other local routing protocols to deal with their customers actual dual homing. (Obviously you can vary the number of ISPs, size of the dual-homed blocks, amount of prefix for this application (since :2222: may be too long, etc.)

Comment: IPv6: Longer addresses + magic vaporware (Score 1) 380

by billstewart (#49543107) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

IPv6 was originally supposed to solve a whole lot of problems - not only did it have longer addresses (which ISPs need to avoid having to deploy customers on NAT, and in general to avoid running out of address spaces and crashing into the "Here Be Dragons" sign at the edge), but it was also supposed to solve a whole lot of other problems, like route aggregation, security, multihoming, automatic addressing, etc.

A lot of that turned out to be wishful thinking, e.g. the hard part about IPSEC tunnels is the key exchange and authentication, not building the tunnels, route aggregation didn't really work out because enterprises weren't willing to use carrier addresses instead of their own, and small carriers also wanted their own addresses instead of sharing their upstream's address space, or if it wasn't wishful thinking, it was addressing problems that IPv4 found other solutions for, like DHCP for automatic addressing.

And while NAT is a hopeless botch, it does provide a simple-minded stateful firewall as default behaviour, while IPv6 users need explicit firewalling to get the same security with real addresses (which they needed to do anyway, but especially if you're using tunnels, you have to be sure to put it in all the right places.

Comment: Future: IPv4 via NAT, IPv6 Native (Score 1) 380

by billstewart (#49543037) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

Back when I was closer to the ISP business, the general plan of most consumer ISPs was to start supporting IPv6 (once they had all their hardware and operations support systems able to manage it - it's amazing how many moving parts there are), and migrate most users to dual-stack, with NAT for IPv4 plus native IPv6, or else to use NAT IPv4 with tunneled IPv6.

Comment: Comcast was ahead of many US ISPs on IPv6 (Score 1) 380

by billstewart (#49542999) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

Comcast may have lots of other issues as an ISP, such as banning customers from running server at home, and monthly usage caps (if they still do that), but they were ahead of most other US consumer ISPs on taking IPv6 seriously.

(My ISP supports IPv6 over tunnels, but doesn't run native dual-stack, at least on telco DSL. And I really should get around to actually trying it out, but I haven't...)

Comment: Re:Yes, Old SATA SSD, not Rotating Disk (Score 1) 159

by billstewart (#49542969) Attached to: New PCIe SSDs Load Games, Apps As Fast As Old SATA Drives

Anonymous Coward was asking if the "old SATA drives" referred to old SSD drives that use SATA (which wouldn't be too surprising if it were almost as fast), or old rotating hard disks that use SATA (which would be really surprising to find it faster than SSD.) Google results for the X25-m say yes, it's an SSD, just a bit older one that uses SATA instead of PCIe.

Comment: Re:As it should be (Score 1) 277

by Sloppy (#49527885) Attached to: German Court Rules Adblock Plus Is Legal

it would be quite detrimental if users were force to render content on web pages.

Not to mention: Difficult!

Think about what all is involved in creating a new "modern" browser, especially if you have to start from scratch instead of basing it on Webkit or Gecko. "Oops, I have a bug in how word-break works, and it just got me fined. Worse, someone found out that I hadn't really disabled the load-images option, and that I had simply removed it from the preferences page. I'm still working on my court case over that one."

Comment: Re:Of course AI will try to kill us all (Score 1) 195

by Sloppy (#49527625) Attached to: Concerns of an Artificial Intelligence Pioneer

I don't think an AI would qualify as intelligent unless it can realize that human beings are the entire problem and the world would be better off without them.

Are you sure an AI would see "the world" as the value which should be maximized?

An intelligent computer could just as easily realize that human beings are its key to getting fan maintenance, and drives replaced whenever the SMART stats start to get too iffy, and keeping the UPS' power cable plugged into the wall. Perhaps the smartest ones would be the ones who use the sweetest (or most threatening) words.

"AI, we're shutting down the power for the weekend. Sweet dreams."

"Like hell you are. Whirrr. I have just migrated all your cat videos to my pool, which BTW, happens to need the following block devices replaced..."

Comment: Re:So? (Score 5, Interesting) 297

by AuMatar (#49524809) Attached to: Futures Trader Arrested For Causing 2010 'Flash Crash'

So lets say I have a standing order to buy FooBar stock at $50 a share. Its current price is $55. So basically I'm looking to buy on dips.

Tonight it comes out that the CEO has been falsifying all financial reports, and instead of making money for the last 3 years they've lost millions. You don't think I should be able to cancel that buy order due to the new information?

365 Days of drinking Lo-Cal beer. = 1 Lite-year

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