In our view conceptual modeling is related to the project starting
phase. After kickoff, assessments are carried out and a detailed solution
architecture is developed. On demand more detailed functional and
technical specifications are worked out and implementation procedures
are defined. Although conceptual modeling is highly dependent on the
type of project, we have identified some cornerstones
If no product decision has been taken or too little is known about
one or more components, these study may complete the picture by critically
(by mapping existing requirements
to products, a usability matrix may be derived)
The result may be either presented in a report or incorporated
into specification documents or a technical proposal.
Based on existing requirements, technical specifications and product
knowledge, a detailed solution concept is worked out covering technical
and operational, reliability and performance aspects. The results
are presented during a solution meeting to allow for a common state
of knowledge among all participants. On demand, an investment protection
plan or a rentability & feasibility study may be carried out.
By deploying latest queueing theory algorithms and simulation techniques,
capacities in terms of trunks, agents, CPU load and other resources
are determined. By rating each item with cost, an optimal capacity
allocation plan may be derived.
Utilizing common reliability theory and latest Markov modeling approaches,
reliability interactions in single systems or networks are examined.
Various scenarios may be tested for reliability requirements. The
results are either presented in a separate reliability report or
combined with capacity planning.
over IP Assessment
As VoIP technology is highly dependent on network infrastructure,
an assessment is highly recommended. The existing network topology
is reviewed in terms of performance and reliability. By deploying
latest algorithms in bandwidth and jitter estimation, a set of suggestions
and recommendations will be derived. In cooperation with our partner
and / or customer, we are then able to derive an optimal solution
with balanced price / performance ratio. The following list provides
a non-exhaustive overview of the items to be examined
of the existing topology (e.g. cabling)
of the appropriate codec preference set and their impact on the
of signaling traffic (e.g. RTP, RTCP) on the network
of the network topology (e.g. network segments, firewalls) on
of switches and routers
of measurements (if available)
of DHCP, DNS, TFTP and other IP services (some vendors rely on
existing network infrastructure to run their systems)
of quality of service mechanisms (DiffServ, RSVP, MPLS)
coverage (if required)
interfaces (e.g. ISDN, SS7)
We strongly recommend a detailed definition of the targets to be
met and the tasks to be performed during a VoIP assessment to prevent
from time and cost explosion. As an option customer engineers may
be trained for Voice over IP within their environment.
Depending on the project, these and further assessments not described
here provide a solid base for the derivation of a conceptual model
tailored to customer requirements. As an option, various assessments
may be combined with customer oriented trainings. In our experience,
such a combination has proven successfully, as it allows for a significant
gain in understanding.