| Business | Phone |
| Go 2 Call Dot Com Inc 801 Warrenville Rd, Lisle 60532 | (630) 795-1075 |
| Lucent Technologies 2600 Warrenville Rd, Lisle 60532 | (630) 577-0470 |
| Smart Telecom Concepts 2300 Cabot Dr, Lisle 60532 | (630) 245-9070 |
| Tellabs Operations 2588 Oakton Ct, Lisle 60532 | (630) 357-8817 |