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Re: [nm-wg] HopList

Yep.

The HopList type is just a number with a (totally useless) units, since the only reasonable unit is "hops".

Martin Swany has some rather specific ideas on a better way to represent traceroute. Here are some slides from a CAIDA workshop:

http://www.caida.org/outreach/isma/0406/slides/imdc-swany.pdf

To me, this implies that traceroute results should be represented as:

( src, dest, TTL ) -> ( IP, [RTT] )

i.e. for a given probe you have src/dst and TTL, and you get an IP [possibly none] and, optionally, the RTT. I say optionally because it seems to me that the RTT isn't very useful without the IP, but not vice-versa (let the nitpicking begin!).

in the "new" subject/param/operation/data setup, I think this would be

subj: src,dst
param: TTL ; ICMP or UDP ; max TTL, etc.
operation: {ggf-blessed}.traceroute
data: IP [,time]

So, how to go forward? I have limited time for this right now, so I'll open the floor...

-Dan

Tanya Brethour wrote:
We were trying to add traceroute to the Advisor and upon closer inspection
of the schema result type HopList.. there does not seem to be any way to
actually list the hops. 
From the nm_result.rnc document:

HopList =
## Number of hops
 element hopCount { xsd:int },
 element units { token }


So what exactly are units for? And second, shouldn't there also be a
"array" of nodes?

Thanks,
Tanya