Q: Internet drops with Yosemite

Wi-Fi?

Wi-Fi: How to troubleshoot Wi-Fi connectivity

Wireless Diagnostics

renew lease in network settings

There are definite bugs in Yosemite that need to be addressed by Apple. Multiple people are experiencing Wifi issues with fresh installs of Yosemite.

I was experiencing consistent Wifi issues after a fresh install of Yosemite.  I validated that it wasn't my computer or router by doing a fresh re-install of Mavericks.  Wifi works flawlessly under Mavericks but always fails under Yosemite. No other software was installed as part of this test.

Here is my configuration:

Model Name: MacBook Pro

  Model Identifier: MacBookPro8,1

  Processor Name: Intel Core i5

  Processor Speed: 2.4 GHz

  Number of Processors: 1

  Total Number of Cores: 2

  L2 Cache (per Core): 256 KB

  L3 Cache: 3 MB

  Memory: 10 GB

  Boot ROM Version: MBP81.0047.B27

  SMC Version (system): 1.68f99

  Serial Number (system): C2QGV006DVHJ

  Hardware UUID: XXXXX

  Sudden Motion Sensor:

  State: Enabled

I am having same problem at once per session.  I have to reboot modem and Airport extreme.  It has mot happened with any other updates