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Chapter 5 ■ Service Design
To state a few examples of SLRs, the customer might ask for critical incidents to be
resolved within the hour, might ask for changes to the systems be implemented within a
day, and might ask for 100% availability of Internet service. Not all SLRs are feasible, even
by the top service providers. In fact, the cost of services tends to go up exponentially as
the service-level requirements hit the high percentage. So, the art of negotiation is to find
the balance between the service levels and the cost of providing services.
Then there are some SLRs which are impossible to match, even by the best of service
providers, perhaps implementing system changes within a day. Not all changes may be
feasible given the timeline, as changes need to be developed, tested, and then deployed.
It takes a lot of planning, coordinating, risk measures, and countermeasures. If the service
provider signs off on an SLR stating that all changes would be implemented within a day,
he would be setting himself up for a grand failure.
Ideally SLRs are captured in the service strategy phase by the service portfolio and
business relationship management processes. But, this is at a high level. Specifics are
not discussed until the agreements are charted. When the contracts are set in stone, the
ball passes to the service-level management to obtain specific requirements from the
customer, who then translates them into workable SLAs.
When SLRs have been determined, the next activity is to come up with servicelevel
targets (SLT). SLTs are hard to come up with in the first instance. Generally, initial
SLTs are defined, and over a period of time, they are refined and finalized. SLTs are a
commitment made by the service provider against an aspect of a service. Examples of
SLTs might be:
• More than 95% of the incidents will be resolved within 8 hours
• Configuration management database (CMDB) will be greater
than 99.5% accurate
When SLTs are agreed to, they go into the SLA document. SLAs are finalized, signed
off on, and then make their way into an addendum to the business contract. I will explain
this process in detail in the next section.
5.7.1.3 SLA Frameworks
SLAs can be drafted in a number of ways. The two most popular types in vogue are
service-based and customer-based SLAs. Figure 5-4 illustrates the service- and
customer-based SLAs.
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