Dear Sir,
How long it will take to implement?
It will take one day to implement .
3 days for any progress my appear in your requirements .
Similiar project you've worked on.
I worked before on serial ports using C# for two projects , interfacing it with Bluetooth & AVR micro controllers for smart metering systems .
Service VS Application
My general rules of thumb are as follows
If it needs to always run, it's a service.
If it needs to be run under a particular user account, Network Service, Local System, generally it's a service (or a COM+ application)
If the user needs some control over it, it's generally a notification area application.
If it needs to notify the user of something, it's a notification area application
For this I prefer it to be an application as serial communication is interrupt driven .
Best regards,
Abduallah Adel