User's Guide

22 Service Level Agreement 73
7signal Ltd, Panuntie 6, FI-00620 HELSINKI, FINLAND, [phone], [e-mail], www.7signal.com
7signal Sapphire Carat Carat User Guide Release 3.0
22 SERVICE LEVEL AGREEMENT
Service Level Agreement (SLA) groups a number of KPIs and their expected target values. In a
nutshell, typically a KPI has a scalar value while SLA is combination of numerous KPI values and
statistical rules that result in a higher-level view on the quality of the network.
The ultimate goal is to bind together a contractual agreement and actual measurements, the
expression of the desired or required level of the service and the proven real-life phenomena.
As such, the SLA is a communication medium between the service provider and the customer.
The SLA outcome is percentage value and based on user-defined thresholds it is divided into
values green, yellow and red according the three-basket principle. This means that the end-
user experience on the wlan network might remain adequate but the resulting SLA value is
clearly in the red basket.
Related icons
SLA template SLA KPI definition
SLA group KPI definition
22.1 Defining a Service Level Agreement into the system
A network service provider can make Service Level Agreements (SLA) with their customers,
defining the level of service provided to the customer. 7signal Sapphire enables users to
monitor the fulfillment of the various performance level guarantees defined in the SLA.
The user may freely choose the performance indicators to be monitored in the
service level agreement, in effect forming out of them an SLA group.
22.2 Defining SLA Key Performance Indicators (KPI)
In 7signal Sapphire an SLA group is formed out of a set of Key Performance Indicators
corresponding to the SLA. The SLA group is bound to a topology element in the monitored
network. Network topology elements that an SLA group can be bound to are Organization, Link
and Link Group.
An SLA group consists of several KPIs which define the boundary values used in monitoring the
fulfillment of the service level agreement.
SLA definitions are inherited throughout the network topology as follows:
If an organization has an SLA group bound to it, the performance indicators defined in
the group are inherited by all links and link groups in the organization.
If a link group has an SLA group bound to it, only the performance indicators defined
in the group's own SLA group are applied regardless of whether the organization
above it has an SLA group bound to it or not.
If a link has an SLA group bound to it, only the performance indicators defined in the
link's own SLA group are applied regardless of whether the link group or organization
above it have SLA groups bound to them or not.
In the 7signal Sapphire system the boundary values can be set separately for each KPI
contained in the SLA group. Each KPI defines a certain type of boundary value and percentage