Talk:B8ZS

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Correction on T-1 line parameters.

The article on B8ZS reads:

"Sending eight zeros in a row could cause T1 equipment to lose synchronization with the sending equipment, it is important that that pattern is not sent."

The actual parameter, which is called the "Ones Density Requirement", says the transmitter cannot send more than 15 consecutive 0-bits and must generate an average of 12.5% 1-bits. I reality, the T-1 systems can often support much longer strings of 0-bits, but the 15- 0's rule is based on the minimum stability of the clocking circuits.

[edit] B8ZS Meaning & Strings of 0's

My own memory is that B8ZS stands for Bipolar with 8 Zeros Substitution".

Concurring with above comment on support of longer strings of 0, the approximate number of consecutive 0's that modern T-1 system support is about 80. However, when sending data, even longer strings of 0's are probable. Thus some treatment of long strings of 0's is always necessary. LoopTel 05:33, 30 November 2006 (UTC)

[edit] Why with B8ZS, still only PTP, and not switched, is supported for CCC

Switched service requires signaling, which indicates to the switch where to send the data. For T1, unlike E1, the robbed bit signaling is used, which would then cause errors for CCC. Thus for T1, even with B8ZS, only 56 Kbits/s can be switched. LoopTel 15:06, 8 December 2006 (UTC)

[edit] Bri encoding

There seem to be a lot of discussion about T1 and E1 encoding. Wikipedia is however very silent about bri encoding Is there anybody around here who know what bri use as an encoding mechanism?

Wikipedia is silent on "bri encoding" because you failed to write anything. I have never even heard of "bri encoding". (Are you sure it's spelled "bri encoding" ? Google only gives me 17 hits for "bri encoding" today, which suggests it is non-notable -- or perhaps a typo.) Or are you talking about the ISDN BRI interface? --75.19.73.101 06:30, 3 December 2007 (UTC)