of the triggering events, the person to be con-
tacted if the problem occurs, the format of the
complaint, the step-by-step process for trou-
bleshooting, etc. The time period for resolving
the problems should also be defined. Usually,
an escalation matrix4)should be agreed on as
well.- The process of monitoring and reportingthe
performance and quality delivered. Here, the
issues of measurements, which type of statis-
tics, how often, where the measurements
should be undertaken, the data collection,
analysis, access to past statistics, etc. would
usually be described. More details on this pro-
cess will be given later in relation with the
QoS part of an agreement. - The consequences and the reaction pattern
for the cases when either the user or the
provider did not obey what was agreed in the
SLA. Additionally, the constraints on the user
behaviour may be included (e.g. for a telecom
service it may imply the request for adequate
type of equipment, for example a PC with
given characteristics thay are necessary to
experience the quality as agreed). Escape
clauses may be included to define when the
statements from the agreement do not apply –
e.g. a fire damaged the provider’s equipment,
etc. - Legal issues, which include the legal identifi-
cation of the parties involved, responsible per-
sons who are members of the SLA team,
terms under which the SLA is not valid, when
is it broken, etc. - Economic issues, which may include tariffing
policy, prices, charging schemes to be applied,
penalties to be paid in case any of the events
triggering the reaction pattern are detected, etc. - Regulatory issuesthat may be extremely
important and may include references to the
directives restricting further retail of the ser-
vice contracted, etc. - Other issuesthat may include specific anthro-
pological, ethical, ethnic issues that are of spe-
cific relevance for a customer or provider.
Handling SLAs and their negotiations is simpli-
fied if they have a generic structure, i.e. a tem-
plate that can be reused for any service, business
case and technology a provider might be dealing
with. Summarising – an SLA should simply
specify what the user will get and what the
provider is committed to provide. Different
types of SLAs are made and negotiated for dif-
ferent services, as discussed in the next section.3.1 Generic SLA types
Various types of SLAs can be recognised having
different aspects/parameters in focus. For exam-
ple should be noted the differences in content
and format of information relevant to different
users and providers.Regarding the content, an SLA can be general/
universal and made on a ‘one-suits-all’ strategy
when offered to e.g. a large segment of residen-
tial customers, or it can be more specific,
adjusted specifically to customer needs, i.e. ‘cus-
tomer-tailored’, suitable for a particular business
customer. Regarding the details included in
descriptions/statements given in the SLA, in
case the SLA is made between the provider and
the residential user, the granularity of parameters
would be chosen naturally so it fits a large num-
ber of customers. That means that the selection
of parameters will be easy to understand, and
should not be expressed strictly technically.Even the language used to describe for example
QoS issues/parameters would be less technical
and understandable to the actual user. On the
other hand, an agreement between two providers
would be more complex (e.g. include more
parameters) and expressed in more technical
terms. For example, the end-user can understand
that its service will be unavailable for less than
5 minutes per month, which actually in technical
wording is equal to an availability of 99.99 %.Regarding the dynamics in the SLA negotiation
and contracting period, commonly for outsourc-
ing services in industries other than telecom (e.g.
catering, etc.) a negotiation period runs from six
weeks to three months, depending on the scope
and volume of the contract, while a contracting
period runs for 3–10 years. In telecommunica-
tions, the dynamics of SLAs is more pro-
nounced, since an SLA may be contracted for
different time scales. The granularity of time
varies from monthly/yearly (e.g. telephony ser-
vice subscription, monthly subscription to the
Internet Service Provider (ISP) for the Internet
access service, renting out a fibre) up to very
short periods like 10 minutes, or per session (e.g.
one transaction for e-shopping, accessing ftp
server, downloading certain content, etc.). The4)An escalation matrix indicates the hierarchy/degree of importance of problems, and the informa-
tion necessary to solve the problems. This information may include e.g. persons to be contacted,
alarm description, messages to send out, format of messages, etc.