Transmission refers to the network entity that transports bulk traffic between network nodes. This transport is over a carrier, on which everything is packed and stacked.

Participants will learn about transport network which can be divided into various layers, such as Access network, Metro Access, Metro aggregation, Core, and Backbone. Briefly,

• Access network provides the last mile communication from Customer Premises Equipment to the network.
• Metro access network is the one which connects access nodes to aggregation nodes.
• Core network consists of core layer switches. This layer is mainly used to provide interconnectivity among different users.
• A backbone is a part of network that interconnects various pieces of network, providing a path for the exchange of information between different LANs or subnetworks.

Transmission medium is the mean through which signal is transferred from one place to another. There are two types of media used in transmission medium. These are guided media and unguided media. Guided media are the physical links through which signals are confined to narrow path. Unguided media is the wireless media.

There are two type of transport mode which are mostly used. These are Microwave and Optical fiber.

Multiplexing is used to send multiple signals over a common high capacity transmission media, such as copper or fiber.

Major transport technologies that are used in transmission network are:

• Plesiochronous Digital Hierarchy or (PDH)
• Synchronous Digital Hierarchy or (SDH)
• Dense Wavelength Division Multiplexing or (D-WDM)
• Coarse Wavelength Division Multiplexing or (C-WDM)

These will form good part of the learning content of the overall course.