rewrite in professional way

  

We use a mid-level SFP i.e. Wide Band 10G SFP Longer Reach (SFP-10G-ER) which costs $4,110 at both ends as it has a loss tolerance of 20db (4-(-16)). The wavelength of this SFP is 1550 nanometre. Our total path length is 67km which is calculated by the given formula (1+6+10) km. So, the fiber loss for this SFP is 0.2db per km that makes a total of 13.4 dB of loss. Now we add to that a splice loss of 0.2db every 5km as we choose splice instead of an amplifier, we have total of 13 splices in our spans that makes it 13*0.2 dB= 2.6db. Then we add 3 connectors loss of 0.5db *3=1.5db. So, in total worst case we face a loss of 17.5 dB loss which is less than the allowed limit of losses as we have calculated earlier. 

Alternatively, we could use a Wide Band 10G SFP Long Reach SFP-10G-LR but we would have to use an amplifier on the span of 67 kms that would increase the cost of the system. But the given solution has an edge of few dollars becoming the cheapest solution. Also if we consider using the Wide Band 10G SFP Longest Reach SFP-10G-ZR it would highly increase the reliability of our system and thus overall performance of the system and also would have a margin of loss tolerance if more splices are introduced or the span is increased but the cost of this system would be very expensive, and the aim of this assignment is to provide the cheapest solution. The total cost of the current/cheapest system is $33000