Ok the steps I described will need to be altered a little as you are connected with a network but if you follow these then you should be in business.
Having an IP address for the machine is fine and not a problem
On your Brother Driver Disc for Windows will be a PPD file. It is usually under /Driver/PS/HL2070N/PPD
First of all copy this PPD file into /usr/share/cups/model/ on your linux system.
Next Restart the CUPS Deamon by typing in a terminal window /etc/rc.d/init.d/cups (you will need to login as root, or login as a super user by entering su)
Open up a web browser and enter http://127.0.0.1:631
This will load the web based printer config utility.
Click on manage printers to add your printer. (You maybe asked to login as root so have these details to hand)
Enter a name and description for your Printer. Click continue.
Choose LPD/LPR Host or Printer. Click Continue.
In the White Box delete anythjing there and enter lpd://the address of your printer ie lpd://192.168.2.2
Click continue and then Choose Brother from the list.
Click continue again and then choose your model.
Click continue once more and your machine will be ready to print
I hope that this helps. Let me know the outcome