-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] On Behalf Of william(at)elan.net Sent: Monday, March 19, 2007 3:20 AM To: virendra rode // Cc: Rubens Kuhl Jr.; NANOG list Subject: Re: SLA monitoring and reporting to customers
How is that part of SLA? Or do you mean you gurantee that your own upstream network connection would not be overutilized? ... accuracy of what? what type of errors, packet drops?
SLA's are simply contracts that two parties negotiate...any number of metrics can be decided upon as the 'agreed level of service'. Different kinds of providers obviously have different metrics that are important - while the availability of services is pretty ubiquitous, accuracy and utilization might not make sense for an ISP SLA...then again they're often deal-breakers for an ASP SLA.
You wish to tell me you guarantee network connection to customer to be down for no more then 5 minutes during the year? Yeh, right :) (but don't let me discourage any of you in trying to achieve it!)
Maintenance Windows / Planned Downtime are nearly always present and defined in an SLA, and should be excluded from the calculation of x number of 9's. Furthermore, all SLAs I've come across also include 'Emergency Windows' which can happen anytime given a pre-determined amount of forewarning. Limits of duration and frequency of these windows should obviously be agreed upon in any good SLA. Bottom line: it's good practice for an SLA to define exactly what metrics are being used, who is measuring them (read: third party, i.e. Keynote), how they are measuring them (software/tools), what constitute a violation and what the recompense should be. - Gregori