When you install an Adobe Creative Suite CS3 or a Creative Suite CS3 point product on Windows, Apple's Bonjour for Windows is installed and registered as a Windows service on the machine.
When you install an Adobe Creative Suite CS4 or Creative Suite CS4 point product, Bonjour is not installed as a separate Windows service . The same networking technology is still used in Creative Suite CS4 and Creative Suite CS4 products. It is implemented internally instead of installing and registering a Windows service.
Bonjour is an open source implementation of zero-configuration networking software. It is used to dynamically discover Version Cue servers on the local network so you do not need to connect to them manually by name or IP address.
For automatic discovery of Version Cue servers on the local network to function correctly, you must allow Bonjour access to the internet through your firewall. Bonjour checks to see whether the DNS server configured on your computer supports service discovery. No data is transmitted to Adobe. Bonjour connects to no other servers than your machine's pre-configured DNS server. Bonjour also sends network packets to and receives them from a multicast IP address on the local network (244.0.0.251) once every thirty minutes. This address is reserved for multicast traffic on a local network and such network packets never leave the local network.