Online Issues > December 2000 > Get Remote Computer Accessand Save
Your old 486 computers will run like Pentium IIIs. Get Remote Computer Accessand Save BY DAVID VINNEDGE
The model doesnt rely on blue sky or untested technology. In fact, it applies 10-year-old technology, which is being used by more than 100,000 organizations, including most of the Fortune 100. The idea is to run all the offices computersno matter where they are, off a terminal server.
THE BENEFITS Before we disclose details about the solution, lets check out its advantages. It will
What makes these benefits possible is a system design that gets back to the mainframe conceptbut without a mainframe. Since todays computers are generally more powerful than yesterdays mainframes, it is possible to designate two powerful computers to function as the serversfulfilling the complete software and data-access needs of many users, whether they are in the office, a satellite office, at home or at a clients. The servers do everythingstore data and application software, perform data processing and, finally, deliver all this to users workstations fast and efficiently. This design removes the burden of data processing from the PC and gives it to the more powerful terminal server. The only things the workstations do is display information on their screens and act as devices for inputting information and inquiries. Thus, when a new software applicationtax preparation or time and billing, for exampleis added to the system, its loaded on the terminal server onlynot on each workstation. Likewise, when an application is upgraded, its configured on the server only; there is no need to administer anything on the workstations. THE SAVINGS The time saved in maintaining each computer on the network is considerable. For example, in a conventional network setup, if you wanted to install a spreadsheet application on all 20 computers in an office, the tech-support person would need to spend from 30 to 60 minutes on each PC. Worse, the tech support person would likely have to do this only when the user was not working at the computer, which would probably turn a 20-hour job into a 40-plus-hour task. But with a terminal server setup, the complete office installation takes no more than an hour, because once the application is installed on the server, its immediately available to all usersno matter where theyre situated. Hardware savings are equally dramatic. Rather than purchase new PCs costing up to $1,500 every two to three years, you can keep the current machines, and over time, as they wear out, replace them with terminals that cost less than half the price and never need upgrading. The initial setup for each new terminal takes less than 10 minutes from box to desktop. THE CITRIX SOLUTION It is best to have separate servers performing distinct functions for this network; an application file server and a terminal server. The application server stores applications and data, distributing the information over the network. Its operating system should be either Microsoft NT or Novell. The second server acts as the terminal server, running virtual workstations. Its operating system should be either Microsoft NT 4.0 Terminal Server or Windows 2000. The software application central to this setup is Citrix MetaFrame. While the system can run workstations without Citrix, omitting it would result in an overall decrease of system speed. One Pentium III processor can service 15 concurrent users logged on at any given time. Calculating the number of concurrent users often requires some estimating. For example, with 20 users in the office, an argument could be made that only 15 would be logged on at any given time. However, keep in mind that during busy periodstax season or the monthly closingextra staff may be brought in or the entire staff could be working on their computers. For a 20-user office it would be wise to get a terminal server that contains at least two internal processors; thus it can handle as many as 30 concurrent users. Terminal servers need ample random access memory (RAM). Its best to provide at least 128 megabytes (Mb) of RAM for the operating system and 32 to 64 Mb for each workstation. Tip: Add a little extra RAM, up to 1 gigabyte; in this case, more is better. Because all the data and programs are stored on the application server, the terminal server doesnt require a large hard disk for storage. Two 9.1-gigabyte (Gb) SCSI drives are adequate. To avoid upgrading disk storage space in a year or two, start with two 18.2-Gb drives. Important: For safetys sake, the drives should be duplexed or mirroredtwo techniques for recording redundant data; doing this provides continuous backup of data. Here are typical prices for such a setupassuming that the office already has one file server (the application server):
THE SETUP Lets see how this
hardware and software arrangement works together. Think
of the terminal server as a very powerful workstation.
When users (theyre called clients in network
jargon) log on from remote locations, they receive their
personal desktop image on their screens. A client can be
many things: a PC (or a dumb terminal without a hard
disk) on a local area network (LAN); a PC at a remote
location connected to the home office via some sort of
communication circuit (point-to-point, dial-up or the
Internet); a remote PC using an internet service provider
(ISP) such as America Online or Mindspring; or even a
PalmPilot. Regardless of how or with what device clients
connect to the server, they receive their own personal
desktop when they enter their user name and password. However, with the terminal server setup, all the processing is done on the central server; that data is not transmitted back and forth. The only transmissions between the server and the workstations are the individual screens for each workstation that display the processed data; and the only transmissions from the workstations to the server are keystrokes and mouse click commands; together, that two-way traffic is relatively light. MAKING THE CONNECTION How do telecommuters connect to the terminal server? Two options are available: a direct telephone dial-up connection to the server (client modem to server modem) or via the Internet. The main advantage of a dial-up connection is securitythe user needs to know the phone number plus a valid user name and password. A direct dial-up connection usually is best if the remote user is within a local calling area and there are relatively few concurrent remote users, say three or fewer. Any more than that and the monthly charges for multiple dedicated phone lines become prohibitive. But there are downsides to that approach: When a user connects modem to modem, the two modems negotiate a mutually agreeable data-transmission speed, which typically is less than optimum speed because of phone line conditions (line noise) or because the two modems may be different brands and speak slightly different languages. As a result, performance when working remotely is usually lower than speed achieved in the office.
The Internet is a better option because it can handle virtually unlimited links without regard to the number of phone lines. As long as the ISP is within the clients local calling area, toll charges arent a problem. If the ISP has multiple local calling areas, then users are able to log into the home office without incurring any toll charges. With this setup, the main office should be connected to the Internet with dedicated Internet accessa T-1 line, a fractional T-1 line, frame relay, cable modem, DSL, ISDN or satellite. Such a connection is limited only by the number of licenses on the terminal server. Speed is comparable to that achieved in the office and the connection is secure. Important: To operate an Internet connection, reserve at least two static Internet Protocol (IP) addresses, one for the Internet connection and one for the terminal server. Caution: Installing a terminal server configuration is not a do-it-yourself job. The real trick is to get all the different applications to work properly together. Turn to a certified consultant with terminal server experience. It will save you both money and headaches in the long run. DOWNSIDES Surely, you may ask, are there downsides to such a setup? There are at least two. A terminal server configuration cannot run all DOS applications; your consultant can identify them before you proceed with the installation. While the initial costshardware, software and labormay deter some organizations from installing such a configuration, those who have done it experience a handsome return on investment based on reduced desktop maintenance, lower PC or workstation costs and simplified network management. In addition, of course, theres the benefit of access to information virtually anyplace at anytime. Whether you have a small or large office, satellite locations, telecommuters or staff who work in client offices, this system can address those needs quite well.
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