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Comment Re:Dual stack failed? (Score 1) 320

Even a tunnel holding 2 devices is usually issued a /64 which will waste 2^64-4 addresses.

I take it you're assuming that each tunnel subnet requires a network and broadcast address? Nope. All you need for a point-to-point link is two IPs, so using a /64 you waste (2^64)-2 IPs. There's a reason I generally prefer using /127s for PtP links, although some implementations don't like that.

Granted, as many other IPv6 proponents are quick to point out, it's not like we need to worry that much about depleting the IP space, but damned if that kind of wasteful thinking doesn't remind me of how we got into such a mess with IPv4.

Comment Re:Dual stack failed? (Score 1) 320

If all the devices in your network only speak IPv6, then the missing you would just need a router that translates IPv6 to IPv4


(of course it will may also need to convert any DNS A record to a DNS AAAA record).


A subset of the IPv6 range is actually allocated to cover the IPv4 address range - basically any address with a maximum value of 2^32 in the 2^128 bit range is an IPv4 address. So your IPv4 address as an IPv6 address is ::D822:B52D.

That's actually slightly dated; it'd now be ::ffff:d822:b52d (although ::ffff: works).

Submission + - After IPv4, how will the internet function? ( 1

An anonymous reader writes: There are 36 countries in the world that have over 100% per-capita usage of mobile phones, this is driving a real crunch on IPv4 addresses as more and more of these devices are data capable. The mobile network operators are acting fast to deploy IPv6 , and T-Mobile USA has had an IPv6-only trial going on for over 9 months now that only uses IPv6 addresses and NAT64 to bridge to IPv4 internet content. It is interesting to note that the original plan for IPv6 transition, dual-stack , has failed since IPv4 addresses are effectively already exhausted for many people that want them. Dual-stack also causes many other issues that has forced the IETF to generate work-arounds for end users called happy eyeballs , which conversely implies eyeballs are not happy with dual-stack, and a big stink around DNS white-listing . How will you ensure that your network, users, and services continue to work in the address fractured world of the future where some users only have IPv4 ( AT&T ), some users only have IPv6 (mobile and machine to machine as well as developing countries) and other internet nodes have both?

Submission + - Politics Hindering OLPC ( 1

explosivejared writes: "Walter Bender of One Laptop per Child (OLPC) said politicians were unwilling to commit because "change equals risk" But, he said, there needed to be a "dramatic change" because education in many countries was "failing" children.

In an interview with the BBC, Nigeria's education minister questioned the need for laptops in poorly equipped schools. Dr Igwe Aja-Nwachuku said: "What is the essence of introducing One Laptop per Child when they don't have seats to sit down and learn; when they don't have uniforms to go to school in, where they don't have facilities?""


Submission + - Social engineering: Are your ID badges showing? (

SarahS writes: "Johnny Long (of Google Hacking fame, interviewed here) claims that the easiest way to "hack" into a company isn't with a computer — it's by putting on a fake ID badge and walking in the door like you mean it. If no one at your company is actually verifying badges, then too bad for you, the social engineer just got inside. In this excerpt on from Long's book, No Tech Hacking, the author explains — with photo proof — why it's so easy for social engineers to create fake ID cards. "Traveling in tech circles, I've seen my share of lanyard clutter, but this nice lady took the prize for most neck-flair toted by a female. As I drew closer, I realized that her badge was decidedly governmental in appearance. ... As she continued chatting into the phone, I swung around to the other side of her and stepped in as close as I could without triggering her (admittedly impaired) stalker detection system. Less than a foot away from her, I snapped the photo below. This particular badge is issued to government employees stationed at the Pentagon. The Post-It note reminds her to "bring a copy of yesterday's all hands to DSS H.Q.'""

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