Does anyone know what the maximum length of a twisted pair should be? I am terminating an analog device on the top floor of a building to a vg224 in a basement and am trying to figure out if it's too far.
We use the VG248 (the VG224 older brother to supply an Analog device at one of our Grounds Buildings which is at least 600m away. This is via a Tie Cable (26 gauge wire). The max distance listed by Cisco is 975m for a phone with 1 REN. The specs are for the ATA, but the VG's are very comparable. Have a look;
This info is from an old Cisco doc;
Q. What is the maximum distance from which I can drive an analog device with a Cisco ATA?
A. Table below provides maximum distances for this question.
In telecommunication, a ringer equivalency number (REN) is a somewhat arbitrary number which denotes the loading a telephone ringer has on the line.
A ringer equivalency number of 1 represents the loading effect of a single "traditional" telephone ringing circuit, such as that within the Western Electric Model 500 desk telephone. Note that modern telephone equipment may have a REN significantly lower than 1: as a rough guide, externally-powered digital-ring phones may have a REN as low as 0.2, while modern analog-ring phones (where the ringer is powered from the phone line) typically have a REN around 0.8.
The total REN for a subscriber's line is simply the sum of the RENs of all devices connected to the line; this number expresses the overall loading effect of the subscriber's equipment on the central office ringing current generator. The local telephone company usually sets a limit on the total REN, typically 5 or less.
If the total allowable REN load is exceeded, the phone circuit may fail to ring (or otherwise malfunction). In extreme cases, the telephone service provider may temporarily disconnect an overloaded line to reduce load.
While REN is a United States-developed yardstick, analogous systems exist internationally. In some countries, (particularly in Commonwealth nations), the REN is better known as the ringer approximated loading number (RAL). In the United Kingdom it is called the ringer equivalence number and a maximum of 4 is allowed on any British Telecom (BT) line.
The short answer is that you don't.... That isn't entirely true while at
the same time it kind of is, but for the most part you don't configure
the softkeys. You enable or disable them via TCL. Here is the long
answer. Be sure to read the whole thing or e...
Topology: IP Phone > Switches > Microsoft NPS setup to forward 802.1x
proxy to > ISE 2.1 patch 3 Authentication: EAP-TLS using Cisco MIC SANs
Phone Models 802.1X support? 802.1x flavor Addtl Comment EAP-MD5 EAP-TLS
Cisco 3905 Y Y N Cisco 6911 Y Y N Cisco ...
This document describe how DST changes and how time changes are
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