E1
acronymISP & telecomnetworking
Stands for: E1 (2.048 Mb/s, 32 timeslots)
The international 2.048 Mb/s digital carrier - 32 timeslots of 64 kb/s, the E-carrier answer to T1, and the line Brazilian networking grew up on.
E1 divides 2.048 Mb/s into 32 timeslots: 30 usable channels, slot 0 for framing and slot 16 classically for signaling (30B+D in ISDN PRI terms), on G.703 physical interfaces. The hierarchy steps to E3 at 34.368 Mb/s before SONET/SDH absorbs the ladder. Everywhere outside North America and Japan, 'dois megas' - two megs - was the business circuit, the Frame Relay access line, and the voice trunk of the dial-up-to-broadband decades. The T1/E1 split is the classic reminder that even the plumbing of telecom forked by region - same 64 kb/s DNA, different arithmetic.
Also known as: e1, e-carrier, e3, 2 mbps, 2 megas, g.703