Re: TTL=Time To Lie?
Anyway.l I think it's a good idea to run probes like this during peak periods just to know how the network is doing, maybe re-route things around bottlenecks, do some load balancing and so on.
That's where the fun begins. CAIDA's measuring across multiple networks, or ASNs in 'net speak. When traffic's traversing multiple networks, ISPs have limited influence over how traffic behaves once it's left their ASN. So your request for say, 4K kitteh videos could go out via an uncongested link, but the video stream comes back in via a congested one. Asymmetric traffic flow is very common. Then there's load balancing, which IP doesn't support, and if it's tried, can just lead to interesting problems with packet re-ordering. Then it can get even more interesting when the traffic's mostly UDP, which is a very dumb protocol. So the easiest solution is to throw bandwidth at the problem, but that's back to arguments over who pays..
Still, I'd like to see some 'standard POSIX tool' that could do this, at any rate. Let's see if it can become a new internet standard.
CAIDA's methods are kinda standard, but their measurements rely on probes. For user-level monitoring, the best tool to use is probably Smokeping, which is available in most flavors of binary.