CHAPTER FOUR: DISCUSSION AND INTERPRETATION OF THE
RESULTS
4.1 DISCUSSION OF THE NETWORK IN NUR
Before we were using the internet connection through satellite
which was in communication with an Earth Antenna VSAT(Very Small Aperture
Terminals ) this is type of antenna is chosen because is directional and very
focus in terrestrial signal transmission here it is a dish located at NUR main
library near NUR ICT center it?s bandwidth was about 2.5 Mbps download and 1.5
Mbps upload at that time connection was faster without interruption but the
cost was high and the bandwidth was small to serve all people in need of
internet connection at our campus it was shared by staffs only and few students
labs.
Nowadays, we have moved to the fiber optic network which is a
grounded optical fiber cable ,the first fiber being implemented was Rwandatel
which is no longer in use at this time then MTN this is currently used and RDB
pipeline which is for government sponsor and is connected to other fibers of
the regions in order to provide high connectivity all over the world and soon
it will be operational in our campus the implementation phase has finished now
it?s time for putting data or signal inside the pipeline .
In addition the type of fiber optic network used at NUR is
single mode fiber optic network because it transmit at long distances without
the attenuation in addition it has Very high bandwidth and Very weak
attenuation 0.5dB/km with 13um and 0.2dB/km with 1.5um very delicate
connections the attenuation occurs at each 100km this is where we can put a
repeater in order to increase signal amplitude and to avoid signal loss during
the transmission phase.
The fiber optic has contribute so much in the increasing of
bandwidth in NUR internet connection through cables and wireless connection now
we have the bandwidth of about 54Mbps upload and download and all over our
campus students and staffs can access the resources offered by the network.
4.2 FIBER OPTIC RESULTS IN BANDWIDTH AND YEARS IN NUR
NETWORK 7 1E0U4.1: U18 5 UNS 1' : , ' 7 + US 1' U 6311
|
YEARS
|
UPLOAD
|
DOWNLOAD
|
ISP PROVIDER
|
|
2005
|
1.5 Mbps
|
2.5 Mbps
|
SATELLITE CONNECTION
|
|
2006
|
1.5 Mbps
|
2.5 Mbps
|
SATELLITE CONNECTION
|
|
2007
|
2.5 Mbps
|
6 Mbps
|
RWANDATEL FIBER
OPTIC CABLE
|
|
2008
|
2.5 Mbps
|
6 Mbps
|
RWANDATEL and MTN FIBER OPTIC CABLE
|
|
2009
|
2.5 Mbps
|
6 Mbps
|
|
2010(2Qtr)
|
2.5Mbps
|
6 Mbps
|
|
2010(3Qtr)
|
17 Mbps
|
17 Mbps
|
|
2010(4Qtr)
|
27 Mbps
|
27 Mbps
|
|
2011(1Qtr)
|
17 Mbps
|
17 Mbps
|
MTN FIBER OPTIC CABLE
|
|
2011(2Qtr)
|
54 Mbps
|
54 Mbps
|
This table 4.1 shows us that by the time fiber optic being
installed in NUR the bandwidth has increased rapidly from 1.5 Mbps/2.5 Mbps by
2005 to 54 Mbps/54 Mbps by 2011(2Qtr) this is great positive impact of the
optical fiber transmission on the NUR network and this has been achieved with
the internet service provider ISP called MTN fiber optic cable.
4.3 THE INCREASE IN BANDWIDTH CHART OF NUR INTERNET
BANDWIDTH IN Mbps
40
60
50
30
20
10
0
UPLINK
YEARS
Figure 21 . Uplink bandwidth connectivity assigned to NUR
This portion of a communications link is used for the
transmission of signals or data from NUR to a satellite or to a fiber optic
link.
2.5 2.5 6 6 6 6 17 27
17
DOWNLINK
54
Figure 22 Downlink bandwidth connectivity assigned to NUR
This bandwidth is used by end users who can be a student or a
staff to get information from the internet.
These two figures: figure 21 and figure 22; we noticed that
the uplink speed is roughly equal to the downlink but at our campus we need
more to download than to upload because students are doing research and it is
often that we can upload sometimes we may need to send e-mails and files which
does not require us a huge bandwidth.
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