Delays

["Henk Uijterwaal \(RIPE-NCC\)" <]

On Mon, 12 Jul 1999, Henk Uijterwaal (RIPE-NCC) wrote:

> From: Lars Marowsky-Bree lmb@localhost

> On 1999-07-12T20:11:12,
>    Ingo Luetkebohle ingo@localhost said:
> 
> > TT provides a way to measure *inter*-network delays and that is much better
> > than what most networks currently guarantee: *intra*-network delays. I know
> > of no backbone provider who makes any guarantees about the rest of the net.
> 
> Because it is almost impossibe to guarantee, no sane network provider would
> make guarantees about parts he can't influence.

But, the customer doesn't buy a connection from an ISP in order to get
just access to the network of this ISP, he buys a connection because he
wants to do something useful with it. The fact that the ISP outsources
part of the work to another company is irrelevant to him.

Then, the ISP that just sold the connection, is in turn a customer of a
backbone provider.  The ISP buys bandwidth from them, so they should get
SLA's from the backbone provider that (at least) guarantees what has been
promised to the customers of the ISP.  

And this is where the TT-project can help.  With a test-box at your site,
plus a box at the nearest exchange point, you can measure the delay
between your border routers and the exchange point.  These can be put in
the SLA, which makes the SLA far more usefule than one with just
guarantees on your insternal network.

> > I always found traceroute to be a good tool to show to customers
> > complaining about network performance.
> 
> Actually I disagree again. traceroute is mainly a function of router load
> these days and the numbers / packet loss is NOT that easy to understand for a
> customer as it appears to be.

Besides the technical issues, traceroute is also a snap-shot.  Your
customer will typically call with a message like "the network was slow
this morning", and then traceroute is not going to help you.  TT delays
provide the history of the delay.

Henk

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The Committee (...) was unable to reach a consensus that substantial merit was
lacking. Thus, the appeal was deemed meritorious.          (Orlando NABC #19).