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What external factors inhibit VoIP transmissions, over RJ45 jacks, and Category 5, 6, 7, cable?

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There are several possible issues that will denigrate the signal, both within your building, and outside your premises. The issue to remember is how the transmission is being sent. This is high capacity broadband cabling, not just simply twisted pair, (category 3, 2, 1). It sets up a field that does digital transport. This field can be, and often is compromisable. The most obvious issue is any device that sends out interfering signals, that is in the direct path of the cable run. This is especially true of fluorescent lighting, due to the ballast in the fixture. If you must run in a plenum with the fluorescent fixtures, it is very important to bypass them as much as possible. Crossing over the top back of the fixture will almost always degrade the signal. Other possible sources of interference include industrial power transformers, and similar power supplies. A second problem is in the cabling between the phone and the wall. Many times it will run under a desk and carpet protector, which may allow the user to roll over the cable and collapse the field, even though the cable will still have continuity, it is compromised, and cannot track full digital signaling. Another issue to be aware of is the actual cable itself. It is not very forgiving of being bent over 70 to 80 degrees. A tight ninety bend, that is very common in electrical installations, often does not translate well into Category 5,6,7 digital runs. Avoid tight bends or excess loops of cable in the plenum area, and maintain the radius on the cable turn , avoiding constriction of the cabling. Out side your facility is beyond your control, and is the responsibility of the service provider. Do be aware however, that in multi tenant buildings, one installation contractor, may "move" the wires set by another. This is the old "my wire is more important than yours" thing. In multitenant installations,expect this to happen occasionally, as other new tenants move in, and watch for decreased productivity in your installation. The problem may be insufficient bandwidth, or it may be a non-affiliated contractor issue.

Last Updated on Friday, 02 March 2007 10:26