If you are about to start working towards the Network+ IT certification from CompTIA, I would strongly recommend downloading the exam objectives from the CompTIA web site. However, below are my study notes, mainly, so I always have the information to hand, but they may be of use if you are planning on taking the exam yourself at some stage. They should help you get started.

1.0 – Network Architecture

1.1 – Network Devices

1.2 – Networking Services & Applications

1.3 – Install and Configure Network Services

2.0 – Network Operations

3.0 – Network Security

4.0 – Troubleshooting

5.0 – Standards, Practices & Theory