Thus spake Aaron Nabil
The original T1 spec was 3 ones in 24 bits, with no more than 15 zeros. But the AT&T spec, (ie, the defacto standard) requires one pulse every 8 bits, not just 3 every 24.
Hrmm...all I can go on is my experience, what I've read, and what I've talked to telco folks about...I have almost never heard it put as no more than 8 zeros...virtually everyone I've talked to about it says it can be up to 15 zeros. This includes websites of many equipment vendors that make this stuff (including at least Lucent, Motorola, Cisco, and virtually every T1 tutorial/overview site that I've found...oh...and the U.S. Department of Agriculture...don't ask me why, but that one turned up).
The reason I said it should be forgotten was because it is a term that has different meaning in different contexts, of which your example would almost always be the LEAST likely to be what someone meant. Most typically by ZCS people are referring to "a ZCS technique" like B8ZS, ZBTSI or HDB3, not one-stuffing done by a CSU.
OK...again...I've never heard of ZCS used those other ways...only as the bit-stuffing...though I have heard plenty of other terms for it as well...I'll be careful in using that then...thanks for the warning. -- Jeff McAdams Email: jeffm@iglou.com Head Network Administrator Voice: (502) 966-3848 IgLou Internet Services (800) 436-4456 - To unsubscribe to usr-tc, send an email to "majordomo@xmission.com" with "unsubscribe usr-tc" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message.