Bonjour, Apple's implementation of zero-configuration networking (Zeroconf), provides three key functions:

1. Address assignment (link-local addressing when DHCP isn't available)
2. Name resolution (via Multicast DNS)
3. Service discovery (DNS-SD)

Your understanding is partially correct - Bonjour doesn't create IP networks but enables automatic configuration within existing networks. When devices connect physically (via Ethernet/WiFi), Bonjour-equipped devices can automatically assign themselves IPv4 addresses in the 169.254.0.0/16 range (IPv6 uses fe80::/10) if no DHCP server exists.

Bonjour operates at the application level - simply running Bonjour doesn't make a computer discoverable. Applications must explicitly register services. Here's the technical breakdown:

// Conceptual service registration flow
1. App → Bonjour: "Register service _http._tcp on port 8080"
2. Bonjour: Multicasts DNS records to local network
3. Other devices: Maintain cache of available services

Windows Bonjour includes dns-sd command utility:

# Register a service
dns-sd -R "My Web Server" _http._tcp . 80

# Browse for services (returns name, IP, port)
dns-sd -B _http._tcp

Output appears asynchronously - press Ctrl+C to stop browsing.

While PHP doesn't have native Bonjour support, you can:

Option 1: Execute shell commands

<?php
// Discover HTTP services
$services = shell_exec('dns-sd -B _http._tcp');
preg_match_all('/(\d+\.\d+\.\d+\.\d+).+port = (\d+)/', $services, $matches);
$service_list = array_combine($matches[1], $matches[2]);
?>

Option 2: Parse mDNS responses

<?php
$socket = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
socket_bind($socket, '0.0.0.0', 5353);
socket_set_option($socket, IPPROTO_IP, MCAST_JOIN_GROUP, [
    'group' => '224.0.0.251',
    'interface' => 0
]);

while (true) {
    socket_recvfrom($socket, $buf, 2048, 0, $ip, $port);
    // Parse DNS packet here
}
?>

For production environments consider:

• Avahi: Linux-compatible mDNS implementation
• Network Environment Variables:

  # Windows (PowerShell)
  [System.Environment]::GetEnvironmentVariable("COMPUTERNAME")
  [System.Net.Dns]::GetHostAddresses($env:COMPUTERNAME)

For your Apache/PHP setup:

1. Install Bonjour Print Services for Windows
2. Create registration script:

   <?php
   // Run when Apache starts
   exec('dns-sd -R "'.gethostname().'" _http._tcp . 80');
   ?>

3. Create discovery script:

   <?php
   $services = [];
   exec('dns-sd -B _http._tcp', $output);
   foreach($output as $line) {
       if(preg_match('/\d+\.\d+\.\d+\.\d+:\d+/', $line, $matches)) {
           $services[] = $matches[0];
       }
   }
   print_r($services);
   ?>

---

Bonjour (Apple's implementation of Zero-configuration networking) primarily handles two key functions:

1. Automatic IP address assignment (link-local addressing)
2. Service discovery via multicast DNS (mDNS)

You're partially correct about IP network creation. Bonjour can assign IPv4 addresses in the 169.254/16 range (APIPA) when DHCP is unavailable, but its primary strength lies in service discovery rather than network formation.

Bonjour doesn't automatically broadcast computers as services. Applications must explicitly register services using the Bonjour API. Here's the typical workflow:

Physical connection → Network established → Applications register services → Discovery occurs

On Windows with Bonjour installed, use dns-sd command:

To register a service:

dns-sd -R "My Web Server" _http._tcp . 80 path=/index.html

To browse services:

dns-sd -B _http._tcp

For PHP applications, consider these approaches:

// Option 1: Executing dns-sd commands
$services = shell_exec('dns-sd -B _http._tcp');

// Option 2: Using PHP extensions (preferred)
// Install pecl/dnssd extension
$dns = new DNSd();
$dns->browse('_http._tcp', function($service) {
    echo "Found: {$service['name']} at {$service['host']}:{$service['port']}";
});

Bonjour doesn't create persistent files, but you can cache discovery results:

// Example caching discovered services
$cache_file = '/tmp/bonjour_services.json';
if (!file_exists($cache_file) || filemtime($cache_file) < time()-300) {
    $services = shell_exec('dns-sd -B _http._tcp');
    file_put_contents($cache_file, json_encode(parse_dns_sd_output($services)));
}

For Windows 7 PHP development:

1. Install Bonjour Print Services for Windows
2. Verify firewall allows UDP port 5353 (mDNS)
3. Test with ping computername.local

Create a batch file to register your Apache instance:

@echo off
set PORT=80
set HOST=%COMPUTERNAME%
dns-sd -R "PHP Server %HOST%" _http._tcp . %PORT%

• Verify Bonjour is running: net start | find "Bonjour"
• Check service registration: dns-sd -L "My Service" _http._tcp
• Test network connectivity between hosts first