Quick Connect Theory of Operations
One of the main drawbacks of using the Internet over the public switched telephone network (PSTN) is the amount of time it takes to establish a connection to an Internet Service Provider (ISP). There are four steps for establishing a dial-up PPP connection. First, the host modem must dial the ISP telephone number and establish a physical link from the client modem to the server (ISP) modem. Next, the modems perform a handshake to compensate for the analog and digital impairments and connect at the optimum rate. Third, the modem establishes an error-free link using V.42, and finally, the host software performs the PPP login protocol. Typically, this scenario, from off-hook to PPP connection, takes 25–30 seconds to complete. Unfortunately, the time it takes to establish a physical link between the two modems through the PSTN is time-consuming and little can be done to speed things up. Nevertheless, it is likely that we can save a second or so here by qualifying dial tone for a couple hundred milliseconds (instead of 700–800 ms) and shortening the DTMF digit duration and inter-digit delay.

The analog channel consists of the local loop from the client modem to its local central office. The analog channel characteristics (equalizer taps and echo canceller taps) are saved in non-volatile memory from a V.90 (standard train) connection. Similarly, the digital characteristics are saved in nonvolatile memory. On subsequent calls to a fast train-equipped server modem, the client modem examines the answer tone to verify that the line conditions are similar to its saved parameters. If the parameters match, a fast connection is attempted. If they do not match, a regular V.90 handshake commences.

Implications and Usage Models
In the simplest application, quick connect allows users to go from launch to activity in a much shorter time than was previously allowed with traditional standard training times. This improves the user model, and makes the connection more transparent than before. As quick connect is deployed more widely, primarily in central site modems, a different user model can be conceived. With quick connect, the IP connection between the ISP and the client can be maintained, while the physical connection between the POP and the client modem becomes dynamic. When the client requires more information or makes an IP request, the modem quick connects with the central site without having to log on again. This frees up a port when the client is idle, yet allows the user to remain online. This requires changes in the client ISP software and the ISP host software, but allows greater central site port utilization. It allows users to remain virtually online for extended periods of time while using a switched-circuit connection.

What will quick connect do for me?
Very simply, quick connect will shorten the time it takes to make a connection by remembering ("training") the phone line characteristics and storing them for later usage. Typically, the modem handshake (all that noise you hear) takes from 25 to 27 seconds. Surveys indicate that people are quite irritated at this length of time. Quick connect will cut the modem handshake time in half for most calls, a significant improvement.

Will Quick Connect work for me while I'm on the road with my laptop?
Yes. Since quick connect actually "trains" the modem on the first call, all the following calls will be quick connects - faster handshake times. People usually make more than one connection from the same phone line (e.g. hotel) when they are traveling.

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