I. Basic Understanding
1. What is the purpose of the router's PPTP/L2TP Client function?
The router can act as a PPTP or L2TP client to connect to external PPTP/L2TP servers. This is suitable for accessing VPN resources of the PPTP/L2TP type provided by an ISP (e.g., exclusive VPN services from some broadband providers). It allows all devices on the local network to access the VPN network uniformly through the router, eliminating the need to configure VPN connections individually on each device.

2. What is the core difference between PPTP Client and L2TP Client in configuration and use?
The core difference lies in the client type selection and corresponding server adaptation: during configuration, you need to select either "PPTP" or "L2TP" in the "Client Type" option based on the target VPN server type. The PPTP protocol is simpler, while the L2TP protocol offers relatively higher security. Both require filling in the corresponding server's IP/domain name and the username and password assigned by the service provider. The configuration process is otherwise consistent.

3. Is the PPTP/L2TP Client function enabled or disabled by default?
This function is disabled by default. It must be manually enabled and parameters configured in the Web UI before it can connect to the corresponding VPN server.

II. Configuration Preparation
1. What information needs to be prepared before configuring the PPTP/L2TP Client?
You need to obtain four key pieces of information in advance:

• The type of the target VPN server (PPTP or L2TP, which determines the "Client Type" selection).

• The server's IP address or domain name (to be entered in the "Server IP Address/Domain Name" field).

• The exclusive username and password assigned by your ISP or VPN service provider (corresponding to the "User Name" and "Password" fields).

• If the server has special requirements (e.g., VLAN ID), confirm them with your service provider in advance (some scenarios may require adjusting other router parameters).

2. What basic router settings need to be checked before configuration?
Ensure the following two points:

• The router is properly connected to the internet (via SIM card or WAN port, requiring prior completion of "Internet Settings" configuration).

• The corresponding protocol "Pass-through" is enabled in the router's "ALG" function (PPTP corresponds to "PPTP Pass-through" and L2TP corresponds to "L2TP Pass-through"). This function is enabled by default. If it was turned off, it might cause VPN connection failure. You can check and enable it on the "NAT Forwarding > ALG" page.

III. Configuration Operations
1. How to access the PPTP/L2TP Client configuration page?

• Connect a device (computer/phone) to the router: computers can connect via a LAN port (wired), phones can connect to the router's Wi-Fi.

• Open a browser, enter the router access address "tendawifi.com" or "192.168.0.1", and enter the login password to access the Web UI.

• In the Web UI navigation bar, click sequentially on "VPN" > "PPTP/L2TP Client" to enter the configuration page.

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2. What are the complete configuration steps for the PPTP/L2TP Client?
Using PPTP Client configuration as an example (steps for L2TP differ only in the "Client Type" selection):

• On the "PPTP/L2TP Client" page, enable the "PPTP/L2TP Client" function.

• Select "PPTP" for "Client Type" (select "L2TP" if connecting to an L2TP server).

• Enter the target server's IP address or domain name in the "Server IP Address/Domain Name" field (e.g., "113.88.112.220" as in the example).

• Enter the account username and password assigned by the service provider in the "User Name" and "Password" fields respectively (e.g., "admin1" as in the example).

• Click the "Save" button at the bottom of the page to save the configuration.

• Observe the "Status" field; it will display "Connected" to indicate a successful connection.

3. How to confirm the PPTP/L2TP Client has connected successfully?
After saving the configuration, focus on the "Status" on the page:

• Displays "Connected": Indicates the router has successfully connected to the target VPN server. Devices on the local network can access VPN resources through the router.

• Displays "Disconnected": Indicates the connection failed. Check parameter configuration or server status.