Solved: ISDN - ESF/B8ZS vs D4/AMI

Quintin.Mayo · ‎05-14-2018

One of our customers are converting from T1 to a PRI circuit. The customer wants to know can they switch the line coding to ESF/B8ZS for the new PRI circuit. I believe ESF/B8ZS is the standard for PRI's circuits? Can someone explain what is the difference between the two, I believe its the bits being utilized? Any assistance would be greatly appreciated.

Thanks,

Georg Pauwen · ‎05-14-2018

Hello,

I found the below in another discussion, it explains the difference pretty well. Basically, D4/AMI is outdated and I have not seen it used anywhere anymore.

D4/SF and ESF are the framing formats of the digital signal. D4 and SF, which are the same thing, stand for Superframe.

ESF stands for Extended Superframe.

AMI and B8ZS are line code parameters. AMI stands for Alternate Mark Inversion, in relation to framing only allows 56kb channel bandwidth. B8ZS stans for Bipolar Eight Zero Substitution, in relation to framing allows 64kb clear channel bandwidth.

View solution in original post

Georg Pauwen · ‎05-14-2018

Hello,

I found the below in another discussion, it explains the difference pretty well. Basically, D4/AMI is outdated and I have not seen it used anywhere anymore.

D4/SF and ESF are the framing formats of the digital signal. D4 and SF, which are the same thing, stand for Superframe.

ESF stands for Extended Superframe.

AMI and B8ZS are line code parameters. AMI stands for Alternate Mark Inversion, in relation to framing only allows 56kb channel bandwidth. B8ZS stans for Bipolar Eight Zero Substitution, in relation to framing allows 64kb clear channel bandwidth.