Background: Know: measuring performance, planned outages, Recognize: customer minutes lost, MTTR (== responsiveness of support)

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SLA components 1Edit

Service performance: e.g.

- x% of packets have delay less than y sec.

How long is the delay from the time when you pick up a phone to when you hear a dial tone-will you always get the tone within hald a second, or are there times when you will have to wait for half a minute?

- z% availability during normal hours.

How much bandwidth is available- are we talking about 10Mbps or 1Gbps?

Is the service guaranteed to always be available?

-define normal hours(planned maintenance outside those hours)

Are there times when it can be "down"?If so, how long will it be down.

-define leadtime that constitites sufficient warning from provider about planned outages.

How often do such outages occur-is it once a year only, or can it occur more often than that?Are outages announced beforehand so that you can plan around them, or do they happen unexpectedly?

Resonsiveness of support from provider,e.g.

How many transactions per second does your web-housting provider support?

- for event that affect service to u users, ISP(Internet service provider) which provides access to Internet will start acting within x seconds, resolve within y seconds, and give updates every z seconds => lower delay for events that affect ore users.

For example,an SLA could contain a statement such as the following: "During the core business hours(M-F 6a.m. to 8p.m.), thr service provider will respond to incidents that affect five or more users within 10 minutes of defecting the incident. The user will get a status update eery 30 minutes until the problem is resolved. Problems that related to service availability will be resolved within 60 minutes, all orther problems within 4 business hours."

Verification of the above

Service providers typically have their own means of ensuring that SLAs are being met. But if the service is truly critical to your business, you should consider engaging a third-party monitoring company to monitor your SLAs, ideally in real-time, so you can be sure you are getting what you paid for. It's an extra layer of hassle and expense but key for that extra peace of mind. Therefore, verification can be achieved by neutral 3rd party.