Are changes compressed before being replicated?
Yes. Changed portions of files are compressed before being sent for all file types except the following (which are already compressed): .WMA, .WMV, .ZIP, .JPG, .MPG, .MPEG, .M1V, .MP2, .MP3, .MPA, .CAB, .WAV, .SND, .AU, .ASF, .WM, .AVI, .Z, .GZ, .TGZ, and .FRX. Compression settings for these file types are not configurable in Windows Server 2003 R2.