Have your server regularly broadcast its address on a port. Have your client act as a server on startup and listen on the same port.When the real server broadcasts its address, the client will receive a connection request. One you have the server address, ask the server for the information you need (what you call the context).
Le 31 mai 05 � 11:41, Francesco Munari a �crit :
Hi, Eric. Ok, but how can I do this? I think I'm a newbie in this kind of operation, sorry. How can I look to a port of servers in a LAN without knowing their IP? And in this way may I keep the context-awareness of the communication? thank you for you reply Cheers francesco 2005/5/31, Eric VERGNAUD <[EMAIL PROTECTED]>:I'm afraid that is a very verbose way of doing things. The typical way to do this is determine a port, have your server broadcast its IP address on that port, and your clients look on that port to grab the address. Once the address is found, you can safely interact with the server using SOAP over HTTP. Le 30 mai 05 � 22:19, Francesco Munari a �crit :I'm alredy using UDDI4j. The idea is that I don't know where the UDDIregistry can be in the LAN. I assume that the client knows only two things: 1) the network (of course) 2) a "search key" for a particular tipe of service and that's all. The client should send a broadcast SOAP (or XML-RPC) request containing the search method to call on the server with the "key" passed as a parameter and somewhere into the LAN should be a server (or more) with its private UDDI registry that should reply with aresponse containing the result of the invoking of the method contained in the sender's RPC request. The response should contain just the URLof the WSDL file related to the service found.The need of the broadcast message is that the client don't know where(or if) there could be any UDDI registry in the network. With this framework a client can change network configuration (for example, going from a floor to another with a Palm in a wireless LAN) and, after leaving the service provided in the first network, find anotheone similar on the other network only by pressing the button "Refresh":) Francesco 2005/5/30, Martin Gainty <[EMAIL PROTECTED]>:The side effect of a broadcast without authentication is flooding thenetwork with unwanted disovery packets I guess this is OK if you're utilising a high datarate transmission i guess In your case your SOAP Request should look like <?xml version="1.0"?> <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" > <SOAP-ENV:Body> <getTest> <Test>Test</Test> </getTest> </SOAP-ENV:Body> </SOAP-ENV:Envelope> If you want to discover a "SOAP based" web-service based on somecharacteristic such as Business Service Category why not use UDDI4J?Take a look at http://sourceforge.net/projects/uddi4j Martin- ----- Original Message ----- From: "Francesco Munari" <[EMAIL PROTECTED]> To: "Martin Gainty" <[EMAIL PROTECTED]> Cc: <[email protected]> Sent: Monday, May 30, 2005 12:44 PM Subject: Re: SOAP-over-UDP Martins, It is for this reason that I'd like to broadcast a SOAP request instead of a simple XML-RPC message. The goal of my framework is to keep the "context awareness" offered by XML language. If you are sure that there is no way to send a broadcast SOAP request, the last solution, I think, it could be XML-RPC. So, two questions: 1) are you sure ther's no way to send a broadcast SOAP request? 2) In order to send a broadcast XML-RPC message I've to cerate a StringWriter like this (for example)? <?xml version="1.0" ?> <methodCall> <methodName>getTest</methodName> <params> <param> <value> <string>Test</string> </value> </param> </params> </methodCall> Thank's Martin. Francesco 2005/5/30, Martin Gainty <[EMAIL PROTECTED]>:Francesco- You can Broadcast XML-RPC assuming you dont mind flooding your network The question is can you confine your application to using the more basic datatypes supported by XML-RPC vs implementing SOAP features (user-defined datatypes, namespace URI)? Anyone else? Martin- ----- Original Message ----- From: "Francesco Munari" <[EMAIL PROTECTED]> To: "Martin Gainty" <[EMAIL PROTECTED]> Cc: <[email protected]> Sent: Monday, May 30, 2005 6:45 AM Subject: Re: SOAP-over-UDP Grazie! :) Could someone tell me if a simple XML-RPC message may be sent to a broadcast address? A simple message with the medthod to be invoked. In this way I should be able to send a broadcast XML-RPC request with the appropriate UDDI inquiry method; a server (containing a UDDI registry)should receive it, invoke that method and send a reply in XML formatto the sender. It could be a good idea? thank you again! Francesco 2005/5/29, Martin Gainty <[EMAIL PROTECTED]>:benvenuto! Martin- ----- Original Message ----- From: "Francesco Munari" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Saturday, May 28, 2005 5:41 PM Subject: Re: SOAP-over-UDP Thank you all for your very quick reply! I've heard about this SOAP-over-UDP spec (http://msdn.microsoft.com/library/default.asp?url=/library/en- us/dnglobspec/html/soap-over-udp.asp). So, Martin, you say that it could not be a solution? Perhaps it should be an idea using Mark's solution (with DNS).I thought to resolve the problem putting a SOAP envelope into a UDPdatagram, send the datagram to a broadcast ip and that's allfolks...but I don't know how and, as you, Martins, wrote, I was notable to find anybody who has implemented this yet. Can you suggest me another solutions? Thank you very much again!! Cheers, Francesco 2005/5/28, Martin Gainty <[EMAIL PROTECTED]>:Mark/Francesco I would caution on use of UDP as the SOAP Portocols (e.g. HTTP) is/are decidely not UDP but instead a connection-oriented TCP To date I have not seen UDP Ports used for SOAP transmission although since there is no requirement for verifiable connection and or handshakes I would venture to guess UDP is available as the transmission medium but I have not seen any UDP Ports used for SOAP thus far Anyone else ??? Ciao- Martin- ----- Original Message ----- From: "mdonaghue" <[EMAIL PROTECTED]> To: <[email protected]>; "'Francesco Munari'" <[EMAIL PROTECTED]> Sent: Saturday, May 28, 2005 3:14 PM Subject: RE: SOAP-over-UDPHi Franceso, I've worked briefly with the apache soap api, not that familiar with it.Typically a soap message is sent to a single soap server address,which is specified by a url or an ip address, as well as a port. So your server address on the LAN might be something like 192.168.100.2:8080. (I'm not sure what the port is for UDDI, so just using standard TomCat Web Server port). IIRC, you there's a point at which you specify that address in the setup for your soap call. One thing you could try is to change the address to the subnet's broadcast address, 255.255.255.0:8080, assuming a class c network where the first 3 quads specify the network portion of the submask. However, this may not a scalable solution, since the broadcast wouldn'tcarry beyond the physical subnet on which you are located. UsingUDDI todiscover services is one thing, but dynamically discovering UDDIservers is obviously a different problem. It also doesn't address the issue of more than one UDDI server running on the same subnet.A more generalized solution might involve a distributed ip lookupservice, namely DNS. For example when DNS looks up the ip address of Yahoo.com, at some point the actual ip address that serves the request is dynamically assigned to one of dozens (or hundreds) of servers based on a schedulingscheme. You could locally enable DNS lookup, and create an entrybased on some url like "myuddpsever.com", and give it your local UDDI server's ip address, and the rest would be handled within the network. The advantage tothis is your UDDP server could be anywhere and your message wouldstill reach it. hth, Mark -----Original Message----- From: Francesco Munari [mailto:[EMAIL PROTECTED] Sent: Saturday, May 28, 2005 4:58 AM To: [email protected] Subject: SOAP-over-UDP Hi, I'm desperate!I'm trying to find out how to send a broadcast SOAP request to aUDDI registry in a LAN, but I'm not able to do this. I've looked for some example but I've not found anithing. Please...could anybody help me?I'm making a thesis for the University of Florence (Italy) and Ihave to discovery dinamically web service published in some UDDI registry somewhere in a LAN. I have to send a broadcast SOAP request to these UDDI registry (as I wrote few lines above). Of course I'm using Java language.Thank you very much for your help...I'm in a great hurry...thanksvery very much to everyone could help me! Best reguards, Francesco
