Network Design of Company

1.    
Choice of
Equipment and Network cables

Choice of equipment like router, switches depends upon the
requirement of network and their nodes. We have four rooms in a company office.
Board room consists of only 2 laptops so we will use 10/100 base T 4 ports
switch, because there are only two hosts here. In reception there are 2 laptops
and 1 wireless access point, so total 3 nodes so will use 10/100 base T 4 ports
switch here also.

In computer room there are 4 PCs but there is possibility of rising
it 8 and 1 printer. So there are total 9 end host/nodes. So we will use one
10/100 base T 8 ports switch and one 10/100 base T 4 ports switch to cover the
requirement. In office there are 3 laptops and 1 printer, total ports
requirement is 4, but the switch also use 1 port to connect itself to main
switch, and so total 5 ports are required for that. For that we will use 10/100
base T 8 ports switch.

For main switch we will use 10/100 base T 8 ports switch because
all 5 switches are connected to it and also it is connected to modem to provide
connected to all the switches. Wireless router which is access point. It is
placed and installed in such area that covers reception and board room. Modem
provides a medium for internal network to communication and access internet via
ISP.

Network cables are of different types available but we Ethernet
cables. Ethernet cables are two types which will be used here i.e. cross cables
and straight cables. Cables available here are 20m in length and 10 in quantity
of each type. Straight cables are used when devices are different and cross
cables are used when devices are different. So here from switch to end nodes we
will use straight cables. As there are only 10 straight through cables so will
use it in all rooms except office to connect end nodes with switches. Total 9
straight are used for 3 rooms. For office we will use 4 10 Base T twisted pair
cables for connecting end nodes with switches.

Each switch is then connected to  
main switch so devices are same.so we will used cross cables here. There
are 5 switches connected to main switch so there is need of 5 cross cables of
20 m connecting switches to main switch. Main switch is connected to   modem via 10 Base T twisted pair cable. Modem
is then connected to ISP via coaxial cable for internet connectivity.

Physical Topology Based On scalability and Reliability

Physical topology is designed in such a way that I can cover future
growth of company here future is growth is indicated in computer room so used 2
switches of 8 ports which will cover future growth. Currently only 2 nodes are
connected to each switch so there are 5 ports are available in each switch for
connectivity of future PCs or printers. Similarly there are free ports for
future connectivity of devices in switches.

Here each end node is connected to a central switch which defines
star topology. The star network has drawback of the failure of a single central
switch can effect in the letdown of the whole network, except requirements are
prepared for hardware redundancy. Increasing the reliability of the ring needs
the adding of redundant links among nodes. Reliability is enhanced but at great
expense but we have limited resources to provide redundancy but some we can
provide redundancy for future growth.

Choice of Network and comparison of Different Transmission Times

As network is unsure about choice of 10BaseT to upgrade into
100Base T. We have link of transferring 50mb regularly would advise to 100 Base
T for fast transmission of files.

10 Base T,10 Base 5 and 10 Base 2 have a speed of 10mb/s and 100
Base T have speed of 100mb/s. So 100 Base T is better choice for NIC here.

Logical and Physical Topologies Difference and Its Effect on
Transmission

 Logical
topology shows us how network devices seem connected to the operator but a
physical topology is by what means they are in reality inter-connected with
different networking cables  and wires. A
logical topology describes how end nodes in a given network link through its
physical topology.

In a joint media topology, computer systems have unobstructed
entrance to the physical media. The main drawback to this topology is a
collisions which badly effect transmission. If two nodes transmit data on the
given wire at the simultaneously, the frames strikes and destroy both frames.
Routing protocols are included in logical topology which defines the path for
packets which play vital role in transmission. Similarly in layer 2 VLAN
creation can also speed up transmission.