Network Planning and Design
planning consists of the following steps:
Identifying the applications that you intend to use: Computer networking
may be required diverse environments such as Enterprise Resource
Management (ERM), Internet telephony, Instant Messaging (IM), eMail and
others.These in turn are used for estimating the software,
hardware, and traffic requirements.
Traffic Requirements: Computing traffic requirements include several
factors. A few point to consider include-
and documentation of major traffic sources.
of traffic as local, distributed, client/server, peer-to-peer,
terminal/host or server/server.
of bandwidth requirements for each application.
of Service (QoS) requirements for each application
Scalability Requirements:Scalability refers to the extent of network
growth that should be supported.Provision must be made to add users,applications,
additional sites,& external network connections.
Geographical considerations:Consider the LAN and WAN links that may be required.Offices that are separated by large distance can be linked together by a WAN(Wide Area Network). Similarly, building complexes with a compound can be linked
by a LAN(Local Area Network) link. Typically, the LAN links are high band
width (100Mbps) and WAN links are of lower bandwidth (64 Kbps - 2Mbps).
The LANs fall within the premises of a Company whereas WANs are
typically leased and maintained by the Telecom. Hence, WANs are costly and need to be planned and designed with utmost care to
minimize resource consumption.
Availability:The availability of a Network need to be given careful consideration while designing a network.It is the amount of time a
network is available to users over a period of time and is often a
critical design parameter. Availability has direct relation with
amount of redundancy required.The factor considered while computing availability is the business loss
to the Company due to unavailability of the network for a given amount of
time.A right balance needs to be arrived at such that profitability is maintained.
Security and Accessibility:A security plan needs to be devised that
meets the required security specifications. You must specify:
a list of network services that will be provided such as FTP, Web,
Who will be administering the security of these services
the people be trained on security policies and procedures
plan, in case a security breach does take place.
Cost considerations: For LANs, the tendency is to minimize the equipment
cost. That is minimizing the cable cost, minimizing the per port cost, and
the labour cost. For WANs the primary goal is to maximize the usage of the
bandwidth. This is because, the recurring costs for bandwidth are normally
much higher than the equipment or labour cost. Therefore more weightage is
given to reliable equipment, and efficient utilization of bandwidth. Some
factors that influence cost are:
efficiency on WAN circuits by using features such as compression,
Voice Activity Detection etc.
technologies such as ATM that dynamically allocate WAN bandwidth.
both voice and data circuits
or eliminate under utilized circuits.