A port on the client side may need to be known. If the server end has a firewall and they require you to connect from a specific IP address and port. We have several connections to servers that require that.
-----Original Message----- From: IBM Mainframe Discussion List [mailto:ibm-m...@bama.ua.edu] On Behalf Of J R Sent: Wednesday, November 04, 2009 8:59 AM To: IBM-MAIN@bama.ua.edu Subject: Re: Final Confusions on Concurrent Server Multiple concurrent connections between a client and server are achieved by use of so-called "ephemeral ports" at the client end. The port number at the server end is predetermined and fixed so that a client always knows where it has to connect to. It is not necessary that the port number at the client end be known ahead of time since no one needs to connect to it. Rather, a server needs to respond to it and knows what it is from the connection request. ======= > Date: Tue, 3 Nov 2009 17:13:58 -0800 > From: hwill...@megapathdsl.net > Subject: Re: Final Conlusions on Concurrenrt Server > To: IBM-MAIN@bama.ua.edu > > "Shmuel Metz , Seymour J." wrote: > > > In <000001ca5b6c$532d3e30$f987ba...@net>, on 11/01/2009 > > at 10:26 PM, Joe Reichman <joereich...@optonline.net> said: > > > > >Here are my Final Conclusions These can only be one Active Conversation > > >between a Client and Server on a port (if its between two different > > >machines) > > > > If the client is using multiple port numbers then it should be able to > > sustain multiple conversations with a single server. TCP/IP does not allow > > concurrent multiple conversations between a single src-IP:port dst-IP port > > pair. > > Actually, technically speaking, TCP/IP has no concept of a conversation. > TCP/IP provides a reliable point to point connection over which you can have > as many conversations as you want. > > > > > > > -- > > Shmuel (Seymour J.) Metz, SysProg and JOAT > > ISO position; see http://patriot.net/~shmuel/resume/brief.html > > We don't care. We don't have to care, we're Congress. > > (S877: The Shut up and Eat Your spam act of 2003) > > Regards, > Henry _________________________________________________________________ Hotmail: Trusted email with powerful SPAM protection. http://clk.atdmt.com/GBL/go/177141665/direct/01/ ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html ========================== This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to which they are addressed. If you have received this email in error please notify the system manager. This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately by e-mail if you have received this e-mail by mistake and delete this e-mail from your system. If you are not the intended recipient you are notified that disclosing, copying, distributing or taking any action in reliance on the contents of this information is strictly prohibited. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
