PUBLIC MARKS from camel with tag bandwidth

I wrote the program "throttle.c," which you can insert into the tcpserver chain of commands for a qmail smtpd server. It takes one argument: the number of kilobytes per second to let through on the incoming file descriptor. Throttle does not throttle the outgoing file descriptor, because that's usually just status from your mail server. Additionally, throttle will set an alarm, so that any session longer than 15 minutes will expire and disconnect. This affords some amount of protection against lingering sessions that eat up your parallelism limit; I've seen such sessions from presumably trojaned DSL machines connecting to the mail server to send spam.

The Apache module mod_bwshare throttles HTTP requests to Apache 1 and 2 servers for each client IP address independently. The mod_bwshare module accepts or rejects HTTP requests from each client IP address based on past downloads by that client IP address. If the HTTP client's download rate exceeds specified levels, the reponse to the HTTP client is an HTML warning message. A human browser will see a warning message indicating how long to wait. Automatic rampant downloaders will download large numbers of useless warning messages. The original motivation for mod_bwshare was to prevent automatic download of all 900 MBytes of material on one of my web sites which was connected to a 33k modem, which would have taken several days if it had succeeded.

mod_cband is an Apache 2 module provided to solve the problem of limiting users' and virtualhosts' bandwidth usage. When the configured virtualhost's transfer limit is exceeded, mod_cband will redirect all further requests to a location specified in the configuration file.