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Internet Routing, Looming Disaster?
wiredmikey writes "The Internet's leading architects have considered the rapid growth and fragmentation of core routing tables one of the most significant threats to the long-term stability and scalability of the Internet. In April 2010, about 15% of the world's Internet traffic was hijacked by a set of servers owned by China Telecom. In the technical world, this is typically called a prefix hijack, and it happened due to a couple of wrong tweaks made at China Telecom. Whether this was intentional or not is unknown, but such routing accidents are all too common online. While BGP is the de-facto protocol for inter-domain routing on the Internet, actual routing occurs without checking whether the originator of the route is authorized to do so. The global routing system itself is made up of autonomous systems (AS) which are simply loosely interconnected routing domains. Each autonomous system decides, unilaterally, and even arbitrarily, to trust everything it hears from any other AS, to use that information without validation, and to further transmit that information to its other peers..."
And this is news because?
This is how the BGP internet functions. the last proposed solution was to centralize the BGP trust tables, which is likely a WORSE solution.
if you can't trust your peers: go work in another kitchen.
No, each ISP chooses what routes to accept from what peers. It's called a filter. Smart ISP use routing databases like RIPE to verify what they'll accept and reject automatically. Others do it by hand. Dumb ones accept updates from peers without filtering. It's this last group that needs to update their practices.
Anybody who touches BGP needs to understand route filtering.
* Would I trust everything I see from Sprint? Yes.
* Would I trust anything except what I expect from the local ISP I route to? No.
* Would I expect Sprint to execute the same filtering as above? Yes.
BGP nodes should always have filters on their connections that describe what is allowed to be accepted. Every failure I can think of... and I'm sure most notable ones that have happened... have been caused by failure to properly filter incoming routes.
SIG: HUP
...just like every other aging technology that increases its workload and interoperability on a scale that was never originally intended.
He who knows best knows how little he knows. - Thomas Jefferson
before we throw this number around anymore, does anyone know approx. how much internet traffic normally goes through China? is the 15% number 15% more than normal, and additional 15%. a baseline is an incredibly important thing.
every anarchist is a baffled dictator. Benito_Mussolini
It's always amusing when a new pundit discovers exactly how the Internet actually works.
Until they gain enough technical knowledge to be dangerous, they assume that the Internet is just as Hollywood portrays... A rock-solid utility run by the Government that only PhDs and arcanely skilled teenage geniuses can control or understand.
Then they discover just how "fragile" it is, and start telling the people who've been making it work all along that they need to straighten up and fly right, or else a major disaster is going to happen. Good thing they told us.
It's sad that they can't just say "Oh, I guess I didn't understand.". Instead they have to "take charge" of things because otherwise they'd have to accept their own irrelevance, or even (gasp) accept that despite their new-found expertise, they *still* don't really understand.
So straighten up, Cisco... it's obvious to this guy you don't know what you're doing. Fix that BGP thing and do it NOW, you hear him?
Since we are now getting to the final blocks of IPv4, how does this issue effect IPv6? Is this currently an IPv4 issue or will it impact IPv6 too?
Jumpstart the tartan drive.
Overhead. What might take a few milliseconds now takes a few more milliseconds. Not a problem on your little Belkin router, but when you're routing thousands of packets a second, it adds up. You can be sure there are many interests non-technical in nature that would be against raising their latency, even by milliseconds. Particularly, Wall Street.
In April 2010, about 15% of the world's Internet traffic was hijacked by a set of servers owned by China Telecom...
Except of course that after the initial flurry of headlines, analysis showed that the 15% figure was a wild exaggeration, orders of magnitude off...
"would i trust everything i see from bear stearns?"
yes
"would i trust everything i see from lehman brothers?"
yes
oh wait..
I know overhead can be a problem, especially with how much overhead there already is in exchanging information. However, the authentication should only be applied to the packets generated by the routing protocol, and not all packets. Therefore, overhead is limited. That is, unless every packet has to be authenticated. I'm not that far in my studies yet.
When we realize the government has inadequate security we leap together in unison and scream, "Why didn't they fix that loophole before??" But when someone tries to raise awareness about the need to take preventative measures on a large scale, all of a sudden it's "lulz silly journalist." Also, the author is not even a journalist. His name is Ram Mohan, "Executive Vice President and Chief Technology Officer at Afilias, a global provider of Internet infrastructure services including domain name registry and DNS solutions. "
The overhead is only in deciding whether to accept _changes_ to the routing table. If your router design isn't broken, that doesn't have to increase overheads of routing each packet at all.
For example, say I give you a piece of paper with a list telling you where to send stuff. So you just follow that.
Later, I could have a long talk with someone about what should be on a new list, but that does not have to affect you at all.
Once I'm done with that, I pass you the resulting list, and you use it.
In April 2010, about 15% of the world's Internet traffic was hijacked by a set of servers owned by China Telecom.
Wasn't there an article yesterday about how this wasn't true?
It's amazing that in the same breath (definitely on the same page) there are posts promoting/demanding immediate/accelerated acceptance/implementation of IPv6 and then this.
People, wake up - there are significant problems running the current, well compacted address space. Things will only get worse when address space becomes extremely sparse and, for all practical purposes, infinite.
The author complains about "fragmentation of routing tables," but then goes on to talk about route hijacking. Doesn't IPv6 largely fix routing table fragmentation? (Real question -- hoping for answer.) Route hijacking is largely fixed by good routing filter hygiene, as explained in previous posts. Most routing protocols support encryption, which won't help if a trusted router sends you bad routes, but can at least make sure you can tell the difference between trusted and untrusted route updates. I don't think BGP supports encrypted advertisements. Anybody know?
I will create a sig when innovation restarts in the U.S.
Capitalized letters are prefixes, aren't they?
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
I am a tier 1 ISP and wish to send a packet to Sprint. My peering with Sprint is down (for whatever reason). Comcast tell me they can route to Sprint. I have two options: trust them, or don't trust them.
I can't actually say that Comcast are advertising a legitimate route to Sprint. But I also can't tell that they aren't snooping all the traffic, or terminating it at drive-by-malware sites, even if the route *is* legitimate. So there has to be trust at the tier 1 level.
I actually implemented BGP in our equipment (I mean wrote the protocol implementation) and since I'm advertising as opposed to handling heavy routing, the title of the article got me thinking a little.
/24 for your customers, it's very likely you can go straight up to a top teir provider and not be able to get that /24 from an existing pool of addresses. So, they'll get those addresses from somewhere else. The /8 you get it from might already be being routed to another top teir. Then the /10 is routed to a second tier provider elsewhere who then sold the /12 to a provider on another provider and so forth and so on.
/8s that they got at different periods, they could try and recover all the /8s in a /12 by arranging trades.
By now, the top traffic routers are probably facing such a massive problem with fragmentation of address pools, that it has to be getting nearly impossible to perform any form of routing without enormous tables.
I'm speculating now.
These days if you (as an ISP) need a new
A top teir provider might have a routing table of their own which, cached could consume hundreds of megabytes of entries. Since top tier routers may actually have millions of open routes at a given time, the cache has to be HUGE!!! Far more than could fit comfortably in fast RAM (SRAM for example and certainly no in register space within an ASIC).
The point being that top tier routers, if they worked on more optimal lookup tables would probably be able to handle much higher throughputs reliably. Less dropped packets etc...
So, I'd say that fragmentation of the address space is probably murder on the top tier routers. It would make a great deal of sense that ICANN or whoever would attempt to start detangling the address space a bit. In the case of ISPs who often have a huge pool of
Additionally, it might even be possible to recover a few hundred thousand usuable IPs by consolidating the pools and therefore cutting down the massive number of addresses wasted on line and subnet IPs.
I'm pretty sure the "what needs to be done" list could be generated programmatically by data mining.
There'd be a great deal of benefits to it, but at the cost of actually having to do work to make it happen.