Chapter 1: Overview
About ADSL
Asymmetric Digital Subscriber Line (ADSL) technology provides
The ADSL USB Modem is capable of supporting the following DSL standards: ANSI T1.413 Issue 2, ITU G.992.1 (G.DMT), ITU G.992.2 (G.lite) and ITU G.992 Annexes A,B and C as applicable.
Protocol and Device Driver Selection
The ADSL USB Modem can be easily connected to a USB port on the PC via a standard USB cable. The ADSL USB Modem is fully software upgradeable so that new features and updates may be added by simply loading a new version of the device driver onto your PC.
ADSL USB modems employ ATM (Asynchronous Transfer Mode) framing. ATM is a protocol that divides packets into small fixed sized cells for rapid transmission over
Several different protocols are used on top of ATM. The protocol required in your configuration depends on the equipment deployed by your DSL service provider. There are several possibilities:
1.Bridged/Routed Ethernet/IP over ATM (RFC 1483) – This protocol makes the modem appear as a local area network (LAN) device to the operating system.
2.Point to Point Protocol (PPP) Over ATM (RFC 2364) - PPP provides session setup, user authentication (login), and encapsulation for upper layer protocols such as IP (Internet Protocol). The use of PPP makes the modem appear as a dial modem to the operating system.
3.Point to Point Protocol (PPP) Over Ethernet (RFC 2516) - PPPoE combines the
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