This course elaborate design of optical link for long distance communication. Point to point optical link consideration for design. Selection of proper optical source for longer distance communication through optical link. Selection of detector for optical link depends upon the choice of source and data rate transmission. Transmission distance requirement for long distance communication with optical link. Study the data rate requirement for optical link. Type of optical fiber used for long distance communication. Study the system requirements such as optical fiber, source and detector for long distance communication. From the source point of view requirement is emission wavelength, spectral width and output power. Selection of source based on the data rate requirement and output power. The detector requirement based on the responsivity and its efficiency. From the system point of view the power requirement for long distance communication for this source and detector is to be selected. Understand the system loss components include loss at connector at source and detector and splice losses. The rise time budget includes the system time for the successful transmission of data with proper BER. It elaborates the amplifier used for the optical link. There are various types of amplifier used at front end, in between link, before receiver and after receiver. The amplifier suitable for various application is explain in brief. Wide-band optical amplifier is used for long distance communication.