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| Prestige 2602HW Series User’s Guide | ||
Graphics Icons Key |
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| Prestige | Computer |
| Notebook Computer |
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| Server | Switch |
| Router |
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| Telephone | DSLAM |
| Trunking Gateway |
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| Firewall | Wireless Signal |
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Introduction to DSL
DSL (Digital Subscriber Line) technology enhances the data capacity of the existing twisted- pair wire that runs between the local telephone company switching offices and most homes and offices. While the wire itself can handle higher frequencies, the telephone switching equipment is designed to cut off signals above 4,000 Hz to filter noise off the voice line, but now everybody is searching for ways to get more bandwidth to improve access to the Web - hence DSL technologies.
There are actually seven types of DSL service, ranging in speeds from 16 Kbits/sec to 52 Mbits/sec. The services are either symmetrical (traffic flows at the same speed in both directions), or asymmetrical (the downstream capacity is higher than the upstream capacity). Asymmetrical services (ADSL) are suitable for Internet users because more information is usually downloaded than uploaded. For example, a simple button click in a web browser can start an extended download that includes graphics and text.
Introduction to DSL | 43 |