An Integrated Access Device (or IAD) is a customer premises device that provides access to wide area networks and the Internet. Specifically, it aggregates multiple channels of information including voice and data across a single shared access link to a carrier or service provider PoP (Point of Presence). The access link may be a T1 line, a DSL connection, a cable (CATV) network, a broadband wireless link, or a metro-Ethernet connection.
At the PoP, the customer's aggregated information is typically directed into an Add-drop multiplexer or an MSPP (multiservice provisioning platform), which are complex and expensive devices that sit between customers and the core network. They manage traffic streams coming from customers and forward those streams to the PSTN (voice) or appropriate wide area networks (ATM, frame relay, or the Internet).
An IAD is sometimes installed by the service provider to which a customer wishes to connect. This allows the service provider to control the features of the access link and manage its operation during use. Competitive service providers are now offering access services over a variety of access technologies, including wireless optical (i.e., Terabeam) and metro-Ethernet networks. Old telco protocols and transport methods (T1 lines and time-division multiplexing) are replaced with access methods that are appropriate for the underlying transport. Because of this, the provider will usually specify an appropriate IAD or install an IAD.
SIAD will aggregate its IP data traffic and GSM ATM traffic at the cellsite passing it along to the multi-service routers sitting in front of mobile switching center (MSC). It will aggregate the cell site traffic and forward to the MSN.