ibm-information-center/dist/eclipse/plugins/i5OS.ic.rzab6_5.4.0.1/protocols.htm

71 lines
4.5 KiB
HTML

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html lang="en-us" xml:lang="en-us">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="security" content="public" />
<meta name="Robots" content="index,follow" />
<meta http-equiv="PICS-Label" content='(PICS-1.1 "http://www.icra.org/ratingsv02.html" l gen true r (cz 1 lz 1 nz 1 oz 1 vz 1) "http://www.rsac.org/ratingsv01.html" l gen true r (n 0 s 0 v 0 l 0) "http://www.classify.org/safesurf/" l gen true r (SS~~000 1))' />
<meta name="DC.Type" content="concept" />
<meta name="DC.Title" content="Socket protocols" />
<meta name="abstract" content="Protocols provide the network transportation of an application's data from one machine to another (or from one process to another within the same machine)." />
<meta name="description" content="Protocols provide the network transportation of an application's data from one machine to another (or from one process to another within the same machine)." />
<meta name="DC.Relation" scheme="URI" content="characteristics.htm" />
<meta name="DC.Relation" scheme="URI" content="../rzahj/rzahjconappcpi.htm" />
<meta name="copyright" content="(C) Copyright IBM Corporation 2001, 2006" />
<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 2001, 2006" />
<meta name="DC.Format" content="XHTML" />
<meta name="DC.Identifier" content="protocols" />
<meta name="DC.Language" content="en-us" />
<!-- All rights reserved. Licensed Materials Property of IBM -->
<!-- US Government Users Restricted Rights -->
<!-- Use, duplication or disclosure restricted by -->
<!-- GSA ADP Schedule Contract with IBM Corp. -->
<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
<link rel="stylesheet" type="text/css" href="./ic.css" />
<title>Socket protocols</title>
</head>
<body id="protocols"><a name="protocols"><!-- --></a>
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
<h1 class="topictitle1">Socket protocols</h1>
<div><p>Protocols provide the network transportation of an application's
data from one machine to another (or from one process to another within the
same machine).</p>
<p>The application specifies the transport provider on the <em>protocol</em> parameter
of the<span class="apiname"> socket()</span> function.</p>
<p>For the AF_INET address family, more than one transport
provider is allowed. The protocols of Systems Network Architecture (SNA) and
TCP/IP can be active on the same listening socket at the same time. The ALWANYNET
(Allow ANYNET support) network attribute allows a customer to select whether
a transport other than TCP/IP can be used for AF_INET socket applications.
This network attribute can be either *YES or *NO. The default value is *NO.</p>
<p>For example, if the current status (the default status) is *NO, the use
of AF_INET over an SNA transport is not active. If AF_INET sockets are to
be used over a TCP/IP transport only, the ALWANYNET status should be set to
*NO to improve CPU utilization.</p>
<div class="note"><span class="notetitle">Note:</span> The ALWANYNET network attribute also affects APPC over TCP/IP. </div>
<p>The AF_INET and AF_INET6 sockets over TCP/IP can also specify
a type of SOCK_RAW, which means that the socket communicates directly with
the network layer known as Internet Protocol (IP). The TCP or UDP transport
providers normally communicate with this layer. When you use SOCK_RAW sockets,
the application program specifies any protocol between 0 and 255 (except the
TCP and UDP protocols). This protocol number then flows in the IP headers
when machines are communicating on the network. In effect, the application
program is the transport provider, because it must provide for all the transport
services that UDP or TCP transports normally provide.</p>
<p>For the AF_UNIX and AF_UNIX_CCSID address families, a protocol
specification is not really meaningful because there are no protocol standards
involved. The communications mechanism between two processes on the same machine
is specific to the machine.</p>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="characteristics.htm" title="Sockets share some common characteristics.">Socket characteristics</a></div>
</div>
<div class="relinfo"><strong>Related information</strong><br />
<div><a href="../rzahj/rzahjconappcpi.htm">Configuring APPC, APPN, and HPR</a></div>
</div>
</div>
</body>
</html>