Apple Broadband Tuner

Current Version: 1.0 (November 29, 2005)

Apple Broadband Tuner is an official "patch" from Apple that tweaks selected network settings on Mac OS X 10.4 to increase the performance of FiOS-based high-speed Internet connections. From the Broadband Tuner home page:

"The Broadband Tuner allows you to take full advantage of very high speed FiOS based Internet connections that have a high latency. The installer tweaks some system parameters.

"There is an optional uninstaller that can be used to restore the settings that were in effect at the time just before the system parameters were changed.

"The installer increases the default values for the size of the TCP send and receive buffers. With larger buffers more data can be in transit at once. A startup configuration file is also updated so that these changes will persist across restarts.

"The system parameters are sysctl variables that are set as follows:

• net.inet.tcp.sendspace: 131072
• net.inet.tcp.recvspace: 358400
• kern.ipc.maxsockbuf: 512000

"This change has a system wide effect and is applied even if the network is not high speed connection with a high latency, with the exception of modem connections for which the system uses small default TCP buffer sizes."

Drew notes: This program, which is written as a series of Perl scripts, does its magic by writing to (or creating, if necessary) your /etc/sysctl.conf file.

Please note that this is for one very specific type of Internet connection (FiOS), and Apple has clarified this since releasing the software on 11/28/2005.

I'd prefer to see Apple release this as (part of) a Preference pane rather than a klunky installer/uninstaller package. I would imagine that Apple plans precisely this (or perhaps an automatic variant) for a future release of Mac OS X.