<?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="reference" /> <meta name="DC.Title" content="Physical environment for frame relay" /> <meta name="abstract" content="This topic provides information about interface options for connecting equipment to a frame-relay network." /> <meta name="description" content="This topic provides information about interface options for connecting equipment to a frame-relay network." /> <meta name="DC.Relation" scheme="URI" content="rzak3overview.htm" /> <meta name="copyright" content="(C) Copyright IBM Corporation 2000, 2006" /> <meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 2000, 2006" /> <meta name="DC.Format" content="XHTML" /> <meta name="DC.Identifier" content="rzak3physenviron" /> <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>Physical environment for frame relay</title> </head> <body id="rzak3physenviron"><a name="rzak3physenviron"><!-- --></a> <!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script> <h1 class="topictitle1">Physical environment for frame relay</h1> <div><p>This topic provides information about interface options for connecting equipment to a frame-relay network.</p> <div class="section"><p>The equipment that attaches to a frame-relay network, such as an IBM<sup>®</sup> <span><img src="eserver.gif" alt="eServer" /></span> iSeries™ system, is the terminal equipment (TE). A frame-relay network node is a frame handler (FH).</p> </div> <div class="section"><p>The connection from the TE to the FH normally exists through a data service unit (DSU) and channel service unit (CSU) pair. This DSU and CSU pair converts the TE physical interface to the FH interface that is used by the frame-relay network.</p> </div> <div class="section"><p>The iSeries system supports three physical interface types for attachment to the DSU and CSU pair:</p> </div> <div class="section"> <ul><li>EIA RS-449, ITU-T V.36</li> <li>ITU-T X.21</li> <li>ITU-T V.35</li> </ul> </div> <div class="section"><h4 class="sectiontitle">Create Network Interface (Frame Relay) (CRTNWIFR) command</h4></div> <div class="section"><p>Use the CRTNWIFR command to specify both the physical interface (INTERFACE parameter) and data transmission rate (LINESPEED parameter). The type of physical interface that you specify depends on the cable that you use. <a href="#rzak3physenviron__rzak3device">Table 1</a> lists the supported physical interfaces, cable lengths, network interface (NWI) clock parameters, and the maximum data transmission speed available for each interface:</p> </div> <div class="tablenoborder"><a name="rzak3physenviron__rzak3device"><!-- --></a><table cellpadding="4" cellspacing="0" summary="" id="rzak3physenviron__rzak3device" class="singleborder" frame="border" border="1" rules="all"><caption>Table 1. Device types 2699, 2721, 2742, 2745, 2771, and 2793 high-speed communications IOAs</caption><thead align="left"><tr><th valign="top" width="25%" id="d0e63">Physical interface</th> <th valign="top" width="25%" id="d0e65">Cable length</th> <th valign="top" width="25%" id="d0e67">NWI clock parameter</th> <th valign="top" width="25%" id="d0e69">Maximum data transmission rate</th> </tr> </thead> <tbody><tr><td rowspan="3" valign="top" width="25%" headers="d0e63 ">*RS-449</td> <td valign="top" width="25%" headers="d0e65 ">6.1 m (20 ft)</td> <td valign="top" width="25%" headers="d0e67 ">*MODEM, *LOOP, *INVERT</td> <td valign="top" width="25%" headers="d0e69 ">2 048 000 bps</td> </tr> <tr><td valign="top" width="25%" headers="d0e65 ">15.2 m (50 ft) <p>24.4 m (80 ft)</p> <p>45.7 m (150 ft)</p> </td> <td valign="top" width="25%" headers="d0e67 ">*MODEM</td> <td valign="top" width="25%" headers="d0e69 ">64 000 bps</td> </tr> <tr><td valign="top" width="25%" headers="d0e65 ">15.2 m (50 ft) <p>24.4 m (80 ft)</p> <p>45.7 m (150 ft)</p> </td> <td valign="top" width="25%" headers="d0e67 ">*LOOP</td> <td valign="top" width="25%" headers="d0e69 ">2 048 000 bps</td> </tr> <tr><td rowspan="2" valign="top" width="25%" headers="d0e63 ">*V.35</td> <td valign="top" width="25%" headers="d0e65 ">20 ft (6.1 m) <p>50 ft (15.2 m)</p> </td> <td valign="top" width="25%" headers="d0e67 ">*MODEM, *LOOP, *INVERT</td> <td valign="top" width="25%" headers="d0e69 ">2 048 000 bps</td> </tr> <tr><td valign="top" width="25%" headers="d0e65 ">24.4 m (80 ft)</td> <td valign="top" width="25%" headers="d0e67 ">*MODEM, *LOOP, *INVERT</td> <td valign="top" width="25%" headers="d0e69 ">64 000 bps</td> </tr> <tr><td rowspan="2" valign="top" width="25%" headers="d0e63 ">*X.21</td> <td valign="top" width="25%" headers="d0e65 ">6.1 m (20 ft)</td> <td valign="top" width="25%" headers="d0e67 ">*MODEM</td> <td valign="top" width="25%" headers="d0e69 ">2 048 000 bps</td> </tr> <tr><td valign="top" width="25%" headers="d0e65 ">15.2 m (50 ft)</td> <td valign="top" width="25%" headers="d0e67 ">*MODEM, *INVERT</td> <td valign="top" width="25%" headers="d0e69 ">64 000 bps</td> </tr> </tbody> </table> </div> <div class="section"> <div class="note"><span class="notetitle">Notes:</span> <ol><li>*LOOP requires DCE support for looped clocking.</li> <li>Data transmission rates greater than 512 000 bps might require *LOOP or *INVERT clocking.</li> </ol> </div> </div> <div class="section"><p>On the frame-relay-supported hardware, the specified value for the INTERFACE parameter must match the physical interface and cable that you attached to the input-output adapter (IOA).</p> </div> <div class="section"><h4 class="sectiontitle">CLOCK parameter</h4></div> <div class="section"><p>The CLOCK parameter on the CRTNWIFR command specifies the method by which the clocking function is provided for the network interface. Possible values are:</p> </div> <div class="section"> <dl><dt class="dlterm">*MODEM</dt> <dd>The default value. The modem provides the clocking.</dd> <dt class="dlterm">*LOOP</dt> <dd>Indicates that the data circuit-terminating equipment (DCE) received clock is looped back to the DCE on the data terminal equipment (DTE) transmit clock. This value improves high-speed data transmission, but it is valid only if supported by the modem.</dd> <dt class="dlterm">*INVERT</dt> <dd>All three interfaces support *INVERT.</dd> </dl> </div> </div> <div> <div class="familylinks"> <div class="parentlink"><strong>Parent topic:</strong> <a href="rzak3overview.htm">Frame relay</a></div> </div> </div> </body> </html>