Tenda W15E, User Manual

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keys to encrypt.

AES: Advanced Encryption Standard. AES128/192/256 indicates that it uses
128/192/256-bit keys to encrypt.
ESP Encryption Key It is used to set the ESP encryption keys, which shall be identical of both peers.
ESP/AH
Authentication
Algorithm
The ESP authentication algorithm is configurable when ESP is selected as the Tunnel
Protocol . The AH authentication algorithm is configurable when AH is selected as the
Tunnel Protocol .
The router supports the following three authentication algorithms:

NONE: It indicates that no authentication key is required.

MD5: Message Digest Algorithm generates a 128-bit digest to prevent data tamper.

SHA1: The secure hash algorithm generates a 160-bit digest, which is more difficult
to encrypt than MD5.
ESP/AH
Authentication Key
It is used to set the AH authentication keys, which shall be identical of both peers.
ESP/AH Outgoing SPI
It is used to set the SPI parameters. SPI indicates the security parameter index. SPI,
together with the gateway address and protocol type of the peer router is used to
identity an IPSec security association, which shall be identical with the ingoing SPI of
the peer router.
ESP/AH Incoming SPI
It is used to set the SPI parameters. SPI indicates the security parameter index. SPI,
together with the gateway address and protocol type of the peer router is used to
identity an IPSec security association, which shall be identical with the outgoing SPI
of the peer router.
9.4 Example of PPTP/L2TP Configuration
9.4.1 Networking requirement
A company uses W15E to deploy a network both of headquarter and branch offices. Employees from branch
offices need to access the headquarter resources over internet anytime, and the resources include internal
materials, OA system, ERP system, CRM system and project management system, and so on.
9.4.2 Solution
The VPN service of the router is recommended to address this requirement. Here, the PPTP is taken as the
example to explain the configuration. For how to configure L2TP, you can refer to this example.
The following figure shows the topology.