T1 Carrier System: ENGR 475 - Telecommunications Harding University Jonathan White
T1 Carrier System: ENGR 475 - Telecommunications Harding University Jonathan White
T1 Carrier System: ENGR 475 - Telecommunications Harding University Jonathan White
Jonathan White
Outline
AKA
What it is and what it runs on.
Why a digital network?
Speeds
How it operates (review).
Framing.
B8ZS
Types of signaling
How it gets synchronized
ESF Extended SuperFrame
T1 AKA
T1 Transmission Level 1
Includes the wires, jacks, hardware.
DS1 Digital Signal 1
The digital signal that goes over a T1
Used interchangeably.
E1
What T1 is called everywhere else besides North
America and Japan.
It is at a slightly different speed.
T carrier System
An architecture
What the T1 system is
Standard to transmit voice and data.
A T1 circuit consists of 24 8 bit channels
Each channel is a pseudo 64 kbps voice channel.
This is the standard voice channel that weve been
talking about.
Still sampled 8000 times a second.
Called a DS0
T1 speed: 1.544 Mbps
(Done on the board).
Cost: $70 to $500 a month, leased.
T Carrier System Definition
T1
is a high speed digital network (1.544
mbps) developed by AT&T in 1957.
The carrier system is just multiplies of T1s.
Designed to support long-haul pulse-code
modulation (PCM) voice transmission.
The primary innovation of the T carrier
system was to introduce "digitized" voice.
T Carrier System Layers
DS0 64Kbps 1/24 of T-1 1 Channel