Handbook of Local Area Networks, 1998 Edition:Advanced LAN Interconnectivity Issues and Solutions Click Here! Search the site:   ITLibrary ITKnowledge EXPERT SEARCH Programming Languages Databases Security Web Services Network Services Middleware Components Operating Systems User Interfaces Groupware & Collaboration Content Management Productivity Applications Hardware Fun & Games EarthWeb sites Crossnodes Datamation Developer.com DICE EarthWeb.com EarthWeb Direct ERP Hub Gamelan GoCertify.com HTMLGoodies Intranet Journal IT Knowledge IT Library JavaGoodies JARS JavaScripts.com open source IT RoadCoders Y2K Info Previous Table of Contents Next 4-3NetWare Gateways to the World of TCP/IP and the Internet JAMES E. GASKIN Your network clients are entranced by the Internet, and are constantly asking, begging, and, well, whining, that they want on the Internet themselves. Hundreds of user workstations, ranging from worn-out 386s (maybe even a 286 here and there) to the latest Pentium dual-chip screamers, are scattered around your network. Keeping them all off the Internet is politically impossible, since your boss promised the president all would surf the Internet before long. However, the president didn’t add more manpower or increase your budget. You and your boss now realize you must allow hundreds of NetWare clients access to the Internet, without blowing your capital and manpower projections for the year. Believe it or not, there is hope for you and your network clients. Novell offers their own solution, the IPX/IP Gateway, bundled with IntranetWare. A dozen third party vendors offer alternative solutions, and we’ll examine the ones that appeal to an all-NetWare shop. One quick note—if you have a chance, it’s worth the extra money to get the optional BorderManager package to update your IPX/IP Gateway. The update alone isn’t worth the money, but the extra control, security, and performance boost for Web clients available with BorderManager adds up to a worthwhile upgrade. ADVANTAGES OF GATEWAYS There are two resources always in short supply for a network manager: time and money. IPX/IP gateways save both. Since money is likely more important to your boss than your time is, let’s start there. TCP/IP protocol suites for PC clients cost money, and they require system resources, particularly RAM. Adding TCP/IP to every workstation may cost up to $100 per workstation, depending on the particular TCP/IP software you choose. Adding RAM to support multiple protocol stacks, particularly in older systems, costs money. Yes, Windows for Workgroups, Windows 95, and Windows NT all come with TCP/IP as part of the operating system. If your complete network client list consists of these operating systems, and you have all the TCP/IP addresses you need, you may avoid the gateway or use it strictly for management purposes. If you don’t have TCP/IP included as part of your client operating systems, pull out the checkbook. If you don’t have enough TCP/IP addresses for your NetWare clients to each have an authorized, unique address for use on the Internet, more time and money will be required. Reorganizing your network for new IP addresses is expensive and time consuming. Let’s say you do have TCP/IP available on each NetWare client, and you have the IP addresses necessary to provide one for every user. Who will go to each of the workstations, enable the TCP/IP software suite, and configure the addresses? Do the math: if all goes well, you may need only 20 minutes for each workstation. That’s three workstations an hour. How many workstations do you have? Is the result larger than the number of work hours in a normal year? Has any conversion ever gone well for any large group of users? HOW IPX TO TCP/IP GATEWAYS WORK If you speak only English, and you want to talk to someone who speaks only French, you have three options. One, you can convince the French person to learn English. Two, you can learn French yourself. Or, three, you can get an interpreter. Consider the IPX/IP Gateway, from Novell or a third party, as the interpreter. Data packets reach the interpreter via IPX, and leave via TCP/IP. When the packets return from the Internet, they are converted from TCP/IP back to IPX. Your clients remain with IPX, and the TCP/IP-based applications provide Internet access through the gateway. The key to this translation is the WinSock specification. WinSock started when members of the TCP/IP community had one of their favorite arguments in favor of TCP/IP everywhere thrown back in their faces. “If you guys make such open and standard software,” said a critic, setting them up for the kill, “why don’t applications from Company A work with a protocol stack from Company B?” Oops. The “open and standard” argument worked in favor of the TCP/IP community when speaking of any TCP/IP client communicating with any TCP/IP host, but not when speaking of the TCP/IP clients themselves. In other words, each company’s TCP/IP applications, such as Telnet, FTP, and email worked only with their own protocol stack. The “open” application developers violated the rules by tying their own applications to their own network software. WinSock is the “mayonnaise” between the meat of the client application code and the bread of the network transport layer. Using WinSock rules, developers can write applications using generic network services (such as `get file name') rather than specific function calls for a particular version of network transport software. The first version of the WinSock specifications were released in January 1993. The first shipping version arrived later that year, but wore 1.1 for the version number. Each TCP/IP protocol stack vendor developed their own WINSOCK.DLL program for Windows 3.1. This file was placed in the\WINDOWS directory. WINSOCK.DLL files are tied to the TCP/IP software underneath them. The specification calls for a standard interface on the application side, so all applications can use any WinSock. Previous Table of Contents Next Use of this site is subject certain Terms & Conditions. Copyright (c) 1996-1999 EarthWeb, Inc.. All rights reserved. Reproduction in whole or in part in any form or medium without express written permission of EarthWeb is prohibited. 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