User's Manual

Advanced Configuration
Parameter Description
MPPE Status
: MPPE Status parameter is applicable only when the Authentication Protocol is
configured as “MSCHAP v2”.
Microsoft Point-to-Point Encryption (MPPE) is a protocol for transferring encrypted
data over point-to-point links. The PPPoE client negotiates on the encryption
parameters based on the MPPE Status configured.
The MPPE Status can be configured as following:
• Mandatory: When the MPPE status is configured as Mandatory, the PPPoE
client negotiates the configured MPPE parameters with the PPPoE server. If the
server does not agree to the parameters then the link will not be established.
• Optional: When the MPPE status is configured as Optional, the link is
established with or without encryption depending on the PPPoE server
configuration. If the PPPoE server supports MPPE encryption then the PPPoE
client agrees with the PPPoE server’s MPPE parameters and link gets established with
encryption. If the PPPoE server does not support MPPE encryption then link gets
established without encryption.
• Disable: When the MPPE status is configured as Disable, then the PPPoE client
does not agree to the MPPE parameters suggested by the PPPoE server.
Configure the desired status and click OK.
Stateless Encryption
Mode
: This parameter is applicable only when Authentication Protocol is
configured as “MSCHAP v2” and MPPE Status is configured as
“Mandatory”.
When stateless encryption is negotiated, the session key changes for every packet
transferred. In stateless mode, the sender must change its key before encrypting and
transmitting each packet and the receiver must change its key after receiving, but before
decrypting, each packet.
When stateful encryption is negotiated, the PPPoE server and the client monitor the
synchronization of MPP encryption engine on both the sides. When one of the peer
detects that they are out of sync then the peer should transmit a packet with the
coherency count set to 0xFF(a flag packet); the sender must change its key before
encrypting and transmitting any packet and the receiver must change its key after
receiving a flag packet, but before decrypting.
To enable stateless encryption, select Enable. To enable stateful encryption, select
Disable.
: Enabling Stateless Encryption impacts throughput. It is useful to enable
Stateless encryption when packet drops are more in the wireless link.
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