Google Apps Directory Sync Administration Guide - Manual (Page 57)

Configuration 57
Google Apps Proxy Settings
Provide any necessary network proxy settings here. If your server does not
require a proxy to connect to the internet, skip this page.
Provide the following:
Google Apps Setting Description
SSL Proxy Host
Name
(if needed)
If your server is running behind a firewall that requires
an SSL proxy to connect to an outside server, enter the
proxy host name here.
If you can connect directly to the internet from this
machine, leave this field blank.
Example: firewall02-http.mixateriacorp.com
SSL Proxy Host Port
(if needed)
Your SSL proxy’s host port (if any).
Common ports for SSL proxy are 80, 8080, 3128 and
1080.
Example: 80
SSL Proxy User
Name
(if required)
Your SSL proxy user name (if any).
Example: proxyuser01