Defining Syn Rate Protection - D-Link xStack DXS-3250E Web/Installation Manual

DXS-3227, DXS-3227P, DXS-3250 and DXS-3250E EWS User Guide

Defining SYN Rate Protection

SYN attacks occur when TCP packets are transmitted with connections that cannot be completed. SYN attacks
result in congested network queues, and cause denial of service to legitimate TCP users. SYN Protection allows
network managers to drop illegal TCP packets. SYN Protection rate limiting is defined on a per-port basis. The
SYN protection rate limiting is assigned after security suite rules are applied to packets, ensuring that ACL and
QoS rules are applied to the packets.
To define SYN Rate Protection:
1. Click Advanced Setup > Security Suite > DOS Attacks > SYN Protection. The SYN Rate Protection Page
opens.
Figure 88: SYN Rate Protection Page
The SYN Rate Protection Page contains the following fields:
•
Interface — Displays the Destination interface on which SYN protection is enabled.
•
IP Address — Defines the destination IP address on which SYN protection is enabled.
•
Mask — Defines the Destination IP address network mask. The default is 255.255.255.255.
•
SYN Rate Limit — Defines the maximum connections per second. The field range is 5 - 1000.
•
Remove — Removes SYN Rate Protection from the interface. The possible field values are:
–
Checked — Removes SYN Rate Protection from the interface.
–
Unchecked — Maintains the SYN Rate Protection on the interface.
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