Traditional VPN systems require the user to ask the firewall's administrator of the company to open an endpoint (TCP or UDP port) on the firewall or NAT on the border between the company and the Internet.
傳統的VPN系統需要使用者去請求公司的防火牆管理者，在防火牆或公司與網路間的NAT開放一個終端點(TCP或UD端口)。