| Business | Phone |
| Bottomline Communications 18001 Sky Park Cir # E, Irvine 92614 | (949) 589-4400 |
| Broadwing Communications 18300 Von Karman Ave # 910, Irvine 92612 | (949) 752-8244 |
| Enterprise Communications 18241 W Mcdurmott # A, Irvine 92614 | (949) 474-7770 |
| Express Tel 18301 Von Karman Ave # 470, Irvine 92612 | (949) 851-0300 |
| A T & T 4902 Flagstar Cir, Irvine 92604 | (949) 727-5569 |
| A T & T & T Voice 414 Oak Gln, Irvine 92618 | (714) 708-2175 |
| Atheros Communications Inc 3 Corporate Park, Irvine 92606 | (949) 752-6859 |
| Blue Wave Innovations 19200 Von Karman Ave # 500, Irvine 92612 | (949) 622-5501 |
| American Telephone 7363 E Tierra Buena Lane, Irvine 92614 | (949) 474-7780 |
| C2c Exchange 4 Park Plz, Irvine 92614 | (949) 474-1500 |
| Dmr 17300 Red Hill Ave # 110, Irvine 92614 | (949) 474-5520 |
| Sky Telecom 29 Alexandria, Irvine 92614 | (949) 553-1100 |
| Telspan Inc 4 Park Plz, Irvine 92614 | (949) 260-9990 |