I’ve had endless problems with network connections (specifically SSH) dropping to remote servers in OS X 10.10 (Yosemite), and wasted countless hours trying different ways to solve the problem. Finally I found a solution that works so well I’m shocked that so few people know about it. It’s called Mosh (short for Mobile Shell).
My connections are now responsive, even after I put my workstation to sleep and wake it again.
If you have had any issues with SSH on Yosemite then check it out on the Mosh Homepage.