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What is the Physical Layer of the OSI Model?

The Physical Layer of the OSI Model Explained

OSI Model

The Open System Interconnection (OSI) Model, is a conceptual framework that defines the layers that computer systems use to communicate over a network. In other words, the 7 Layer OSI model characterizes computing functions into a universal set of rules and requirements to support interoperability between different products and software. There are seven layers within the OSI model, each of which has a specific functionality to perform. Together, the layers work collaboratively to transmit the data from one person to another across the globe. It is crucial to raise awareness about why Layer 1 of the OSI model needs to be addressed.

Below is an overview of the seven layers and their individual functions.

Physical Layer of the OSI Model

The Physical Layer – An Explanation

The Physical Layer (L1) is the lowest layer of the OSI model and provides hardware security. This layer is responsible for the actual physical connection between the devices by identifying the equipment involved in the data transfer. Layer 1 defines the hardware equipment, cabling, wiring, frequencies and pulses. The information is contained in the form of bits and transmitted from one node to another.

The problem is that hardware security goes neglected; existing security software solutions do not cover the Physical Layer of the OSI model (Layer 1). Without Layer 1 visibility, the physical specifications of the network are not captured. Hence, network implants – Rogue Devices which operate on the Physical Layer – are not detected. Similarly, spoofed peripherals – Rogue Device manipulated on the Physical Layer – are identified as legitimate HIDs.

Without Layer 1 visibility, enterprises are at risk of Rogue Devices infiltrating their network and conducting harmful attacks. As Layer 1 is the first of the OSI layers, it is crucial to have adequate physical level security protection at this level to stop the attacks originating from Rogue Devices at the very first instant; before being carried out.

June 8th, 2021