How can we make the server access speed faster?

How to make the server access speed faster-Linux Enterprise Application-Linux server application information, the following is a detailed description. I had a server in the school and used Lenovo's desktop business computer. The configuration was okay. What about RMB? I signed a dial-up Internet access for the school and added a TP route. More than a dozen people shared it, I used port ing to map port 80 to my host, and also built a firewall. Why can access some places, some places cannot access, and the network speed is exceptionally slow, just like opening a foreign webpage, what's more, the DNS of the peanut shell that comes with TP clearly shows that it has been connected. Why can't I use the website? Please help us!