SONET

Definition

Synchronous Optical NETwork. A family of fiber-optic transmission rates from 51.84Mbps to 13.22Gbps, created to provide the flexibility needed to transport many digital signals with different capacities, and to provide a standard for manufacturing design. It defines a physical interface, optical line rates, frame format and an OAM&P protocol (OPERATIONS, Administration, Maintenance, and Provisioning).

SONET Rates

OC LEVEL

LINE RATES

CAPACITY

OC-1

52 Mbps

28 DS-1/1 DS-3

OC-3

155 Mbps

84 DS-1/3 DS-3

OC-9

466 Mbps

252 DS-1/9 DS-3

OC-12

622 Mbps

336 DS-1/12 DS-3

OC-18

933 Mbps

504 DS-1/18 DS-3

OC-24

1.2 Gbps

672 DS-1/24 DS-3

OC-36

1.9 Gbps

1008 DS-1/36 DS-3

OC-48

2.5 Gbps

1344 DS-1/48 DS-3

DS stands for digital service. DS-1 is 1.544 Mbps in North America, 2.048 Mbps elsewhere. DS-1 is also called T-1. DS-3 is the equivalent of 28 T-1 channels operating at 44.736 Mbps.

SONET Packet Layout

Chapter 8 of the Goldman text shows the packet structure of the sonet frame. Lets review that layout.

OC LEVEL	LINE RATES	CAPACITY
OC-1	52 Mbps	28 DS-1/1 DS-3
OC-3	155 Mbps	84 DS-1/3 DS-3
OC-9	466 Mbps	252 DS-1/9 DS-3
OC-12	622 Mbps	336 DS-1/12 DS-3
OC-18	933 Mbps	504 DS-1/18 DS-3
OC-24	1.2 Gbps	672 DS-1/24 DS-3
OC-36	1.9 Gbps	1008 DS-1/36 DS-3
OC-48	2.5 Gbps	1344 DS-1/48 DS-3