Introduction 15

Features

❖Data Compression—increases transmission speeds using the new V.44 compression algorithm, which is optimized for World Wide Web browsing. The modem also supports MNP5 and V.42bis data compression protocols.

The internal modem has a modem port (RJ11) for connecting to an analog telephone line.

CAUTION: Connect the internal modem ONLY to an analog line, not to a digital line. For more information, see “Connection procedures” on page 44.

Due to FCC limitations, speeds of 53 kbps are the maximum permissible transmission rates during downloads. Actual data transmission speeds will vary depending on line conditions. Many users will experience throughput in the range of 32 to 44 kbps under normal conditions, depending on telephone line quality.

To achieve a V.92 56K connection, both your modem and the host modem (typically at an ISP) must be V.92 56K modems. As many ISPs do not yet support the V.92 protocol, most connections will be V.90 56K connections.

V.92 connections also require a phone line that supports the V.92 protocol. Some phone lines will not support V.92 or V.90 56K connections at all, either because of quality impairments or additional analog-to-digital conversions (for example, PBX systems).

When a PCM upstream connection is not possible, the modem automatically uses the default V.34 protocol for “upstream” data transmission, which supports connection rates of up to 33,600 bits/ second.