Engineers Ponder Easier Fix To Internet Problem

itwbennett writes "The problem: Border Gateway Protocol (BGP) enables routers to communicate about the best path to other networks, but routers don't verify the route 'announcements.' When routing problems erupt, 'it's very difficult to tell if this is fat fingering on a router or malicious,' said Joe Gersch, chief operating officer for Secure64, a company that makes Domain Name System (DNS) server software. In a well-known incident, Pakistan Telecom made an error with BGP after Pakistan's government ordered in 2008 that ISPs block YouTube, which ended up knocking Google's service offline. A solution exists, but it's complex, and deployment has been slow. Now experts have found an easier way."

Comments

Well????

[Anonymous Coward]

1. Tell everyone routing is broken.
2. Break it.
3. ???
4. Profit.

Please tell us so we can get to 4.

Re:Well????

[dgatwood]

Or crawl through the barrage of bullets muttering something about uptime (obligatory xkcd).

Problem

[girlintraining]

So they've finally solved the problem of repressive governments disconnecting citizens from the internet, preventing the free flow of information, being co-opted by large corporations, and a litany of jurisdictional issues that have caused many people's lives to be ruined?

"No, they just made it so this can only be done by those people, and not your people. Our people are, of course, better than your people, being authoritative, responsible, and all of that."

Bad summary

[jeffasselin]

", but routers don't verify that the route 'announcements.'" what?

Please fix this sentence, it hurts when I try to read it :-(

The big fix...

[icebike]

The solution is to have routers verify that the IP address blocks announced by others routers actually belong to their networks. One method, Resource Public Key Infrastructure (RPKI), uses a system of cryptographic certificates that verify an IP address block indeed belongs to a certain network.

Well duh! You would have thought this was the case already. Why are we worrying about state sponsored cyber attacks if we leave a hole this big wide open?

Can any network gurus out there tell me if this problem still hangs around after ipv6? Does it get bigger?

Re:The big fix...

[Vancorps]

Problem is the same size. If I have two or more routes to the same network then multiple routers are responsible for a given ip block. Its not really an attack vector because your create peering agreements with your providers and they are each responsible for holding up their own end of the deal. As disruptive as BGP errors whether malicious or through fat fingering are, it's not really that big of a deal to fix once the problem is identified.

I would think a DNSSec like infrastructure could help remove the possibility of malicious route modifications but in the end, if it's state sponsored then any system can be broken by even the proposed solution.

Re:The big fix...

[jd]

BGP for IPv6 is essentially the same as BGP for IPv4, so if the protocol has a security hole then it will appear on both. However, because IPv6 is designed from the outset to be a hierarchical addressing scheme, address tables should end up being much smaller (even though each entry is longer) which in turn means that accidents should be less common. If it's easier to see the consequences of your actions, you (in theory) should be less likely to make mistakes.

Back in the days when IPv6 mandated IPSec, the problem of malicious router table poisoning simply wouldn't have existed -- all router protocol traffic would be encrypted and every link would be encrypted distinctly, where the keys used for encryption are securely exchanged in an encrypted form via IKE or IKE2 and where the key exchange encryption key is either a shared secret or a public/private key pair. It would not eliminate accidental corruption, but attacks would be out of the question.

Also back then, automatic address assignment, router and service discovery (via anycasting) and router-level IP mobility (the routers automatically redirected packets if you moved between networks) meant that manual router configuration was almost unnecessary. Virtually everything could be discovered - including MTU - and so nothing really needed to be configured. This would have eliminated manual errors. In fact, that was the whole point of all these automated mechanisms. There would be no manual entry and therefore there would be no manual errors.

Telebit added a nice touch, creating a routing protocol that permitted segments of the network to be transparent (essentially the same as NAT, only far more fine-grained and flexible), although it seems they made the grievous error of not making their protocol public. Certainly I've seen nobody attempt to use it and there has been no reference to it since Telebit went under. Further, the lack of NAT is something that has held back IPv6. Given that Telebit had a working NAT equivalent in 1996, this is incredibly annoying. (Apologies if they did make it public, but it is still true that it's not used and that complaints about a lack of NAT have been a serious issue - made all the more serious precisely because the problem was solved and the solution deployed very very early on.)

So the answer is "if IPv6 is deployed as close to originally intended as possible, the problem simply doesn't exist - in any form; but that if IPv6 is deployed as it is currently used, the hole will hang around although it will be a little smaller".

Re:The big fix...

[jd]

Poisoned router tables will indeed "infect" other routers, radiating out until the correct route has a preferred weighting to the toxic route.

A wonderful example of this occurred in 1995 in England, when Manchester University's computer centre decided that it WAS America. (Now, I know they tend to have an ego problem there, but this was impressive.) Because redirecting traffic to Manchester required fewer hops and utilized greater bandwidth to any other route to America, you can guess what happened next. It took quite some time for the engineers to clean up the mess, because the newly discovered Northwest Corridor^wWormhole had been discovered by so many routers and the information was being gossiped around. Just as with humans, once gossip starts it is very hard to stop - even when the source admits it was false.

There's not a lot you can do in a case like that. Once an authenticated router starts having delusions due to buggy software/hardware, there's not much any other router can do to determine that it truly is a delusion. Multipath helps (if you support dividing traffic between multiple routes, according to viability, you'll only lose a percentage of traffic, not all of it) but you'd need active path monitoring to go any further. Which would reduce bandwidth (which is already excessively limited) and increase complexity (the primary cause of hallucinating hardware).

Congressional Approval

[ComputerInsultant]

Do these engineers have approval from the US government to make these changes? Changes like this could break the ability to break the Internet. Can't have that.

Solution is called Rover, Uses Reverse DNS

[billstewart]

TFA wasn't very detailed either, but it mentions that the new protocol is called Rover. Project website is here. The short summary is that you can use Reverse DNS to advertise the BGP Autonomous System Number (ASN) that's authoritative for your block of address space, and use DNSSEC to protect the Reverse DNS tree. If somebody else starts advertising that they've got a route to your address block, routers (or route servers sitting next to the routers, because your standard router doesn't actually know how to do this) can verify whether that's correct.