Digitalizei através da minha rede doméstica local usandoBonjour 1.0(.NET) para serviços comregtype = "_http._tcp":

 DNSSDService service = new DNSSDService();
            DNSSDEventManager eventManager = new DNSSDEventManager();
            eventManager.ServiceFound += new _IDNSSDEvents_ServiceFoundEventHandler(eventManager_ServiceFound);
            DNSSDService browse = service.Browse(0, 0, "_http._tcp", null, eventManager);

Quando encontro o serviço, o método:static void eventManager_ServiceFound(DNSSDService browser, DNSSDFlags flags, uint ifIndex, string serviceName, string regtype, string domain) é invocado.

Então nesse método eu quero usar o método:DNSSDService GetAddrInfo(DNSSDFlags glags, uint ifIndex, DNSSDAddressFamily addressFamily,string hostname, DNSSDEventManager eventManager) para conhecer o endereço IP e a porta do serviço.

O problema é que eu não sei o questring hostname deve ser e, portanto, não recebo nenhum resultado: ** Por favor, olhe para: ??? O QUE AQUI ?? no código **

 static void eventManager_ServiceFound(DNSSDService browser, DNSSDFlags flags, uint ifIndex, string serviceName, string regtype, string domain) {
            Console.WriteLine("browser: " + browser + "\nDNSSDFlags " +  flags+ "\nifIndex " + ifIndex +"\nserviceName: " + serviceName + "\nregtype: " +regtype+ "\ndomain: "+ domain);
            DNSSDEventManager eventManager = new DNSSDEventManager();
            eventManager.AddressFound += new _IDNSSDEvents_AddressFoundEventHandler(eventManager_AddressFound);
            DNSSDAddressFamily family = new DNSSDAddressFamily();
            browser.GetAddrInfo(flags, ifIndex, family, ???WHAT HERE???, eventManager);
        }

        private static void eventManager_AddressFound(DNSSDService service, DNSSDFlags flags, uint ifIndex, string hostname, DNSSDAddressFamily addressFamily, string address, uint ttl) {
            Console.WriteLine("----------------------------------------");
            Console.WriteLine("FOUND THE ADDRESS");
            Console.WriteLine("----------------------------------------");
        }

Resultado:

browser: System.__ComObject
DNSSDFlags 2
ifIndex 32
serviceName: AXIS M1011-W - 00408CBEEAE5
regtype: _http._tcp.
domain: local.

Código completo:

using Bonjour;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;

namespace WindowsFormsApplication1 {
    static class Program {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main() {
            DNSSDService service = new DNSSDService();
            DNSSDEventManager eventManager = new DNSSDEventManager();
            eventManager.ServiceFound += new _IDNSSDEvents_ServiceFoundEventHandler(eventManager_ServiceFound);
         //   DNSSDService browse = service.Browse(0, 0, "_axis-video._tcp", null, eventManager);
            DNSSDService browse = service.Browse(0, 0, "_http._tcp", null, eventManager);


            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new Form1());
        }
        static void eventManager_ServiceFound(DNSSDService browser, DNSSDFlags flags, uint ifIndex, string serviceName, string regtype, string domain) {
            Console.WriteLine("browser: " + browser + "\nDNSSDFlags " +  flags+ "\nifIndex " + ifIndex +"\nserviceName: " + serviceName + "\nregtype: " +regtype+ "\ndomain: "+ domain);
            DNSSDEventManager eventManager = new DNSSDEventManager();
            eventManager.AddressFound += new _IDNSSDEvents_AddressFoundEventHandler(eventManager_AddressFound);
            DNSSDAddressFamily family = new DNSSDAddressFamily();
            browser.GetAddrInfo(flags, ifIndex, family, ?????WHAT HERE?????, eventManager);
        }

        private static void eventManager_AddressFound(DNSSDService service, DNSSDFlags flags, uint ifIndex, string hostname, DNSSDAddressFamily addressFamily, string address, uint ttl) {
            Console.WriteLine("----------------------------------------");
            Console.WriteLine("FOUND ADDRESS");
            Console.WriteLine("----------------------------------------");
        }



    }
}