All-- In a perfect world, your provider says the service is always on, the service is always on. In the real world, we have to deal with outages -- some kids vandalise a phone box, new tech trips over some cables, some idiot telco misimplements MPLS and brings your service down for a day.... These things happen, and sometimes we all just have to suck it down and deal with it. But if it happens continuously, you have to ask your provider for some assurance that it won't keep happening. This is what SLAs are for. In my experience, a company that delivers reasonable levels of service has no need for SLAs with their clients. The service is up, everybody is happy. SLAs are like your parent telling you to do the dishes again "and get it right this time, or else you go to bed with no jell-o!" Which s why, in looking for a vendor, I ask for an SLA. If they have one as a standard offering, then I know that they've messed up a lot in the past, and will probably be messing up more than I like in the future. It's like the kid who never did his homework coming up to the teacher on the last day of school asking for extra credit. NO YOU FOOL! You should have done it right the last 180 days! Anyway, just my thoughts. On Mon, 27 Nov 2000 Toby_Williams@enron.net wrote:
Date: Mon, 27 Nov 2000 10:14:43 +0000 From: Toby_Williams@enron.net To: nanog@nanog.org Subject: Limits of reliability or is 99.999999999% realistic
SLAs are the point where commercial & operational worlds collide. The numbers being offered should:
Reflect the targeted quality of the service Tie in with meaningful damages for not achieving them
In a market where I can offer 99.7% or 100% and the difference is a whole day's service credit, I know what I'd be offering. No question.
If on the other hand, the expectation is that I pay out a year's contract value in cash upfront every time I miss a target in a month, then I'd only want to offer a target that will *always* be achieved.
In the market at the moment, the situation is much closer to the first scenario than the second - ie damages for SLAs do not mean anything to either:
the buyer, as compensation for not receiving the service that they have contracted for; or the seller as a motivation to work within the targets, because capped service credit agreements do not touch the bottom line
Today, in the IP market, it is irrelevant whether services come with 99.0 or 99.99999 SLAs & at some point the market needs to address the responsibility that if they are to offer a service of a certain "guaranteed" quality, then they should stand-by that guarantee with their money and give this guarantee meaning.
I don't think this is the case at the moment, and that's why we even see 100% SLA in the market - because the level of pay-outs on SLAs don't matter to the seller.
No. I'm not suggesting that sellers offer guarantees for consequential losses. Simply ones that:
1. give the buyer the peace of mind that if the service they've contracted to is below par, that they will have enough money put back in their pocket for them to have replaced their service, like-for-like in the market, to cover themselves over the period.
2. enable the market players to truly differentiate their service offerings by quality, rather than marketing.
Toby [std. disclaimer of responsiblity here]
Date: 25 Nov 2000 20:24:48 -0800 From: Sean Donelan <sean@donelan.com> Subject: Limits of reliability or is 99.999999999% realistic
<snipped for brevity>
But back to my question. �What is the real requirement? �Amazon.COM had system problems on Friday, and their site was unusuable for 30 minutes, definitely not 99.999%. �But what did that really mean? �The FAA loses its radar for several hours in various parts of the country. �What did that really mean? �Essentially every system given as an example of "high- availability, high-reliability" I've looked at, doesn't hold up under close examination.
Is 99.999% just F.U.D. created by consultants?
Instead of pretending we can build systems which will never fail, should we work on a realistic understanding of what can be delivered?