Searching / Displaying Products by Field Type

I know this is probably very easy and I've done it before but right now I've forgotten how :) .

Essentially I have a database of about 200 products and some of them have different technology types (field: land_line_broadband_type). For example in each product that I add to the database I will have a check box list of technology types that I can assign to them:

DSL

Cable Modem (DOCSIS)

FTTH

Now I want to create a URL to my List Viewer PHP file that only shows the products with a technology type of "Cable Modem (DOCSIS)". So far I can do this:..

http://www.MYDOMAIN.co.uk/List_Broadband.php?orderBy=land_line_broadband_type

But I can't remember what form of call I need in order to make sure that only the "Cable Modem (DOCSIS)" assigned products are shown? I know it's something obvious but it's been over a year since I wrote the system :) .