Demarc extensions, short for demarcation point extensions, refer to the extension of the demarcation point within a telecommunications network. The demarcation point is the physical point where the service provider's network ends, and the customer's network begins. Demarc extensions involve the expansion of this point to a location within a customer's premises, facilitating the connection of telecommunications equipment and services. These extensions enable customers to have greater control over the management and maintenance of their internal network. Demarc extensions play a crucial role in ensuring effective communication and troubleshooting by allowing easy access to the demarcation point within the customer's premises.