 must be registered with carrier B's video communication network, even though that carrier does not serve them. Registration requires connectivity tests, a process that can take up to a week. In short, first time, spontaneous connections between dedicated access customers served by different carriers are almost impossible to arrange. Explaining this to a room full of executives who are waiting for a videoconference with an important customer may be stressful. SWITCHED ACCESS The way to avoid this problem is to access an IXC's digital network using switched access service provided by the LEC. Switched access service is service that allows a customer to flexibly route calls across different long distance carrier's networks. To achieve this flexibility, a customer must generally buy their access service from company that is not their long distance carrier. Since the distinction is blurring between long distance carrier and local access providers, it is important to ask the access provider if the switched connection being installed can be used to call anyone, on any other network, by simply dialing their telephone number. Switched digital service choices for video and data conferencing include Switched 56, ISDN Basic Rate Interface (BRI), ISDN Primary Rate Interface (PRI), and asynchronous transfer mode (ATM). Switched access should not be confused with dedicated access service, which may also rely on ISDN PRI or ATM. In a switched access arrangement, channels can be assigned flexibly, to any long distance carrier and a customer can override the long distance carrier assignment by dialing a carrier access code. Long Distance Carrier Access Arrangements When ordering local service, customers are required to select a primary inter- exchange carrier (PIC). The LEC indicates the PIC choice by entering the selected carrier's access code in a routing table or database. When a "1+" long distance call is made-in other words, a long distance call that is not specifically directed to a different long distance carrier-it defaul