The IT role responsible for the installation and maintenance of hardware and software that make up a computer network is the Network Administrator. Their responsibilities include:

Network installation: Setting up and configuring network hardware, such as routers, switches, firewalls, and servers.

Network maintenance: Ensuring the network operates smoothly, performing regular updates, and troubleshooting issues.

Security management: Implementing security measures to protect the network from unauthorized access, attacks, and breaches.

Performance monitoring: Monitoring network performance and making necessary adjustments to optimize speed and reliability.

Therefore, the Network Administrator is the correct role for these responsibilities.

References

William Stallings, "Data and Computer Communications," Pearson.

Andrew S. Tanenbaum and David J. Wetherall, "Computer Networks," Pearson.