Transmission data protection is the description of the security used for the communication of the data. 

This can be Tranmission Layer Protocol (TLP) when considering two or more systems communicating directly communicating with each other over the internet, and securing the communication itself by means of encryption and decryption on either end. 

Other means can be by using (other) VPN technologies, where usually an encryption layer between devices and applications running VPN-type services and applications are being used. 

Public operators such as Internet Services Providers, Mobile Operators, ... in most cases use encryption technologies to protect the data transmssion over the public network, when providing specific business to business services. In 3G, 4G and the up and coming 5G mobile data provisioning transmission data protection has been enabled.

However, operators and platform providers should assure themselves about which transmission data has been facilitated, or should require a security baseline for it. Additionally, digital platform can start providing transmission security as part of the platform. This will be especially necessary when working with edge devices transmitting and cloud platforms receiving data. 

Transmission data protection should also be considered for machines and equipment on site, or nearby. Many robot instructions and  their commands for instance, are being transmitted  in clear text. Many technologies exist today to prevent this from happening, even at high speeds.

The tranmission data itself should also be protected and prevented from leaking. The transmission data can also be used as a control protocol, checking the transmission for arrival and audit.