Network problems or Some other problem? ??

I am backing up a laptop that is connected to my home network wireless.  The backup server is connected to the network wired.  The backup is MUCH slower than when I backup to an external Hard Drive.  I expected it to be somewhat slower but this is too slow.  The full (inital) backup takes about 45 minentes to the external drive.  The full (inital) backup to the backup server over the network has taken 3 hours and is only 19% complete. I have made a number of backups tothe external drive.  Only today did I edit the backup job to back up to the hard drive on the server.  We have maped the backup destination drive on the server as the "X" drive on the laptop.

The partial complete file is named "DamonLaptop_C_Drive004.v2i.tmp"  I have never seen a backup file ending in "tmp" before.  Do I have network problems or some other problem?