Considering faxing over your integrated access T1? Let me provide a cautionary note and a little history before you do. Fifteen years ago customers would purchase a T1 for voice and perhaps some 56K tie lines between facilities for Voice/Modems. If an organization was really large they would buy a T1 between sites. With the widespread adoption of the internet and increased functionality of data networks, customers began to purchase a single T1 for Voice and a second T1 for Data. Enterprising CLEC’s got into the action by dividing up a T1 for Voice and Internet, usually 50/50 for smaller companies. Approximately 5 years ago CLEC’s began to allow the T1 usage to be dependent upon the amount and type of traffic going over it. For example, if you had 2 calls, your Internet access dropped from 1.544Mbps to about 1416K. Once those 2 calls dropped, you had full access to the 1.544Mbps. The technology that made this advancement possible was VoIP; otherwise known as an Integrated Access T1. VoIP can provide T1, ISDN PRI or a POT’s dial tone connection plus Internet. The main problem with this technology is it does not handle faxing very well or in many cases not at all. The cautionary note is do not fax over an integrated access circuit. It might work 30% of the time. For now, keep all fax and modem on analog POT’s or TDM interfaces until the protocol T.38 becomes more prevalent.