Main Page | See live article | Alphabetical index The IBM 3720 was a communications controller made by IBM, suitable for use in an IBM System 390. Official service support was withdrawn in 1999 in favour of the IBM 3745. External Link Do You Use a 3705, 3720, 3725? Based on material from FOLDOC, used with permission. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.