Hi John, I think DHCP server is used to find TFTP server, time server, Gateway, and maybe DNS too. I don't think it can be used to find Printers or other video application or VoIP server etc. Maybe a DHCP expert can comment more on it. Generally DHCP server exist in the Service provider network, thus the customer DHCP Request may have to go through a DHCP Relay agent to reach the DHCP Server. Though DHCP server can also exist in the customer network too. Morever, in Stateless address configuration a DHCP server may not exist too.
IMHO, I feel that address discovery and service discovery are separate and best done by separate server for each. - Abhijit -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Thursday, August 04, 2005 12:22 PM To: Abhijit Chaudhary (abchaudh); ipv6@ietf.org Subject: RE: IPv6 Service Discovery Abhijit, What sort of Application Service are you talking about? I know folks look at using DHCP for configuring this kind of information, if I understand you correctly. John -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of ext Abhijit Chaudhary (abchaudh) Sent: 04 August, 2005 08:23 To: ipv6@ietf.org Subject: IPv6 Service Discovery Hi, I have question regarding IPv6 auto service discovery. Suppose a IPv6 Mobile Host comes and joins a network. Using Stateful or Stateless Address Configuration mentioned in ICMPv6 Router Advertisement message it gets a IPv6 address. But if the mobile host want to know the nearest printer IP address or the proxy address or DNS server address (i.e, IP address of Responder mentioned in draft-ietf-ipngwg-icmp-name-lookups-12.txt). Is there any draft or RFC that talks about a procedure to get information about Server providing application Service for IPv6? If not, I am of the impression that we can add a new option to Router Advertisement message called "Application Service Discovery Proxy". This option will contain the IPv6 address and Link-Layer address of the "Application Service Discovery Proxy". This proxy will contain all the information of the available application service in the network and the corresponding servers. The new option will look as below: +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv6 Address of Application Service Discovery Proxy | + | | +++++++++++++++++++++++++++++++++++++++++++++++ | ~ Link-Layer Address of Service Discovery Proxy | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The Message Exchange is described below: 1) Router Advertisement will contain the Application Service Discovery Proxy Option "Router Advertisement with Application Service Discovery Proxy Option" Router ------------------------------------------------------------------------ ---------------------------------------------------------> Host 2) Host gets the Address of the Application Service Discovery Proxy and stores it. Suppose, the host wants printing service, it uses some protocol (maybe UDP or XML over HTTP or ICMPv6) to discover services from the Application Service Discovery Proxy. For Printing service the message as below: "Give me printer service address" 1. Host ------------------------------------------------------------------------ ----------------> Application Service Discovery Proxy "Printer IPv6 address = x, Printer LL address = y" 2. Application Service Discovery Proxy ------------------------------------------------------------------------ ---------------------------> Host "Sends data to be printed" 3. Host -----------------------------------------------------------------------> Printer Let me know what you guys feel about it. Thanks, - Abhijit -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
