What is oca number?

The OCA number, also known as the Optical Carrier Number or Synchronous Transport Module (STM) level, is a classification used in telecommunications to refer to the capacity of a digital transport medium. It indicates the transmission rate of a fiber-optic network or an SDH/SONET network.

The OCA number provides a standardized way to classify the capacity of optical channels or transport systems, allowing for easy identification and comparison across different networks. It is defined by ITU-T (International Telecommunication Union - Telecommunication Standardization Sector) and ANSI (American National Standards Institute) standards.

The OCA number is represented by a numeral, such as OCA-1, OCA-3, OCA-12, OCA-48, or OCA-192. Here's a breakdown of the common OCA numbers and their corresponding speeds:

1. OCA-1: Also known as OC-1, it represents a transport rate of 51.84 Mbps (Megabits per second). It is predominantly used for low-speed applications.

2. OCA-3: Also known as OC-3, it supports a transmission rate of 155.52 Mbps. OC-3 is commonly used for medium-speed applications, such as high-speed internet access.

3. OCA-12: Also known as OC-12, it offers a speed of 622.08 Mbps. OC-12 is often used in high-bandwidth applications, such as backbone networks.

4. OCA-48: Also known as OC-48, it provides a transmission rate of 2.488 Gbps (Gigabits per second). OC-48 is commonly used in dense data transmission applications, including video conferencing and multimedia streaming.

5. OCA-192: Also known as OC-192, it supports a transmission rate of 9.953 Gbps. OC-192 is the highest bandwidth commonly used in telecommunications and is often used for large-scale data transmission, high-speed internet links, and core network connectivity.

It's worth noting that the OCA number is indicative of the electrical signaling rate rather than the actual data throughput, as some of the capacity is utilized for overhead and control signaling. However, it provides a standardized way to reference the capacity of fiber-optic or SDH/SONET networks and facilitates planning, provisioning, and interconnecting various telecommunications services.