John shares his knowledge of fiber optics by answering your specific questions
Fiber optic installers tell me that singlemode installations are more costly than multimode installations. However, when I compare cable prices, there doesn't seem to be much difference. Are they correct?
Yes and no. Cable costs may be similar, but singlemode connectors are more expensive than multimode connectors and they are more time consuming to install. Likewise, singlemode transceivers are more expensive. However, for long distance applications, these higher costs are more than offset by the fact that singlemode fiber requires less frequent amplification, fewer connectors, and provides more bandwidth.