Brother DCP-L5500DN, User Manual

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- ESP is a protocol for carrying out encrypted communication using IPsec. ESP encrypts the payload
(communicated contents) and adds additional information. The IP packet is comprised of the header
and the encrypted payload, which follows the header. In addition to the encrypted data, the IP packet
also includes information regarding the encryption method and encryption key, the authentication data,
and so on.
- AH is part of the IPsec protocol that authenticates the sender and prevents manipulation of the data
(ensures the completeness of the data). In the IP packet, the data is inserted immediately after the
header. In addition, the packets include hash values, which are calculated using an equation from the
communicated contents, secret key, and so on, in order to prevent the falsification of the sender and
manipulation of the data. Unlike ESP, the communicated contents are not encrypted, and the data is
sent and received as plain text.
• Encryption
Select DES , 3DES , AES-CBC 128 , or AES-CBC 256 . The encryption can be selected only when ESP
is selected in Protocol .
• Hash
Select None , MD5 , SHA1 , SHA256 , SHA384 , or SHA512 . None can be selected only when ESP is
selected in Protocol .
• SA Lifetime
Specify the IKE SA lifetime.
Type the time (seconds) and number of kilobytes (KByte) before the IPsec SA will expire.
• Encapsulation Mode
Select Transport or Tunnel .
• Remote Router IP-Address
Specify the IP address (IPv4 or IPv6) of the connection destination. Enter this information only when the
Tunnel mode is selected.
SA (Security Association) is an encrypted communication method using IPsec or IPv6 that exchanges and
shares information, such as the encryption method and encryption key, in order to establish a secure
communication channel before communication begins. SA may also refer to a virtual encrypted
communication channel that has been established. The SA used for IPsec establishes the encryption
method, exchanges the keys, and carries out mutual authentication according to the IKE (Internet Key
Exchange) standard procedure. In addition, the SA is updated periodically.
Related Information
• Configure an IPsec Template Using Web Based Management
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