Alteon Application Switch Operating System Application Guide
Advanced Denial of Service Protection
614
Document
ID:
RDWR-ALOS-V2900_AG1302
Configuring Protocol-Based Rate Limiting Filters
Rate limiting filters are supported on TCP, UDP, or ICMP protocols only. Protocol-based rate limiting
can be configured for all filter types (allow, deny, redir, sip, and dip) and parameters. Specify the
source IP address and mask options in the Filter Configuration menu to monitor a client or a group
of clients. The destination IP address and mask options are used to monitor connections to a virtual
IP address or a group of virtual IP addresses.
The following examples work for any supported protocol-based rate limiting configuration. To specify
a rate limiting filter for TCP, UDP, or ICMP, set the protocol on the filter itself, then go into the
Filtering Advanced menu to set the rate limiting parameters.
Example
1: A Basic Rate Limiting Filter
The following example illustrates how to configure rate limiting for Filter 10.
1. Set the protocol used for the rate limiting filter. Only UDP, ICMP, and TCP protocols are supported
for rate limiting.
2. Enable rate limiting for the filter.
3. Configure maximum number of connections. The value of 1 indicates a total of 10 TCP
connections (or sessions).
4. Set the time window in seconds.
Note:
The rate limit defined in
as the maximum number of connections over
a specified time window results in 30 TCP connections for every three seconds (or 10 TCP
connections per second).
5. Set the holddur parameter in minutes.
If a client exceeds the rate limit, then the client is not allowed to make any new TCP connections
or UDP/ICMP packets for 4 minutes. The following two configuration examples illustrate how to
use protocol-based rate limiting to limit user access based on source IP address and virtual IP
address.
6. Repeat
to configure other filters.
7. Apply and save the configuration.
>> Main /cfg/slb/filt 10
>> Filter 10 # proto <any|<number>|<name>>
>> # /cfg/slb/filt 10/adv/security/ratelim/ena
>> Rate Limiting Advanced# maxconn 3
>> Rate Limiting Advanced# timewin 3
>> Rate Limiting Advanced# holddur 4