[Asterisk-Users] Difference between E1 and PRI

[Eric Wieling]

Eric Bishop wrote:

> Hi all,
> 
> I have seen the term E1 and PRI used interchangably when referring to
> a voice service with 30B channels and 1 D channel. Are they just
> different terms for the same thing or is there some technical
> difference. Even Newton's telco dictonary seemed a bit fuzzy on this
> topic. I have seen it said the PRi is a protocol that runs on top of
> E1. Is this true?

Think of E-1 as Ethernet (transport) and PRI as IP (protocol).

You could also think of E-1 as IP and PRI as TCP.

You can also think of E-1 as TCP/IP and PRI as FTP.