Options and cost

Last month, I thought I had put the final pieces in place for connecting a Windows-NT based network to the Internet. I planned to set the stage for important topics such as name resolution with the Windows Internet Naming Service (WINS) and comparing WINS to the Domain Name System (DNS). But each month, I receive several letters (thanks!) describing problems in getting on the Net and asking for advice.

The routing and Internet connection issues I've talked about aren't as much fun as building the world's best Web page. Still, routing IP packets can become really exciting when you can't connect to your Internet Service Provider (ISP). So here's one more column on this topic to cover some odds and ends and to answer dozens of pieces of mail about how to connect to the Internet.

Cost of Connecting
Many readers want to know what it costs to connect to the Internet. The answer depends on how you connect. You can choose among three ways.

First, you can get a Serial Line Internet Protocol (SLIP) or Point-to-Point Protocol (PPP) account. With this method, your ISP gives you one IP address.

Yes, you can attach your NT workstation or server to the Internet using Remote Access Service (RAS), and yes, you can participate as a complete node on the Net. However, you probably can't put your entire network on the Internet via one computer. I say probably because you can't use out-of-the-box NT software to let dozens of PCs share one IP address. However, Microsoft plans to ship "Catapult," an Internet proxy server for sharing one IP address over an entire LAN. The idea is neat, but you can't buy it now, and I don't know of any such products on the market.

Second, as my June column explained, you can install a LAN-to-WAN router with a dial-up connection. Third, you can use a leased line rather than a dial-up connection.

If you put your mail server, Web server, FTP server, or Gopher server on the Internet, you need a full-time Internet connection. Although you can use a dial-up connection, it can be expensive (find out the cost of local calling rates from commercial locations in your area). Establishing a full-time connection means your ISP has to dedicate a phone line and modem to you. The ISP will probably charge you accordingly.

If you can afford the per-minute charges on Integrated Services Digital Network (ISDN), a full-time connection can be an excellent application for this technology--find out what it costs before doing it. (For more information, see John Enck's, "ISDN to the Rescue," Windows NT Magazine, May 1996.)

For decent speed, look into a fixed-speed leased line or a variable-speed frame relay line. Low-speed leased lines come in 64Kbits per second (Kbps) and 1500Kbps, sometimes known as DDS and T1. Leasing T1 can be expensive, about $2000 per month for the telephone company's charges, not including ISP fees.

Frame relay leased lines can be a better value and offer a minimum guaranteed throughput, or committed information rate (CIR), and maximum possible throughput (usually twice the CIR). The lowest-level frame relay has a CIR of 32Kbps because it's built on a regular DDS 64Kbps line, so it can temporarily handle up to 64Kbps. Frame relay on T1 usually has CIRs of 256Kbps, 512Kbps, or 768Kbps. Including everything, my ISP charges between $400 and $1300 per month for CIRs of between 32Kbps and 768Kbps. You can save money using higher line rates. ISPs set different rates, but usually the more the ISP costs, the better the tech support.

To connect to the Internet, you need two pieces of equipment: a modem or Digital Service Unit/Channel Service Unit (DSU/CSU) to transfer your bits on the dial-up or leased line, and a LAN-to-WAN router to move the bits to the right location. With a digital leased line, a DSU/CSU handles high speeds on digital lines. Like a modem, a DSU/CSU connects to the router with a short digital cable similar to a serial RS-232 cable. The rating for RS-232 is only for transport speeds up to 20Kbps. Although you can use it for higher speeds, I don't recommend building an important network interface running at 1Mbit per second (Mbps) through RS-232. Another faster, but not as familiar, interface is V.35.

My column in June showed how to cook up a homemade router with an NT workstation, which is not a bad alternative. Still, a dedicated router is cheaper (usually under $2000) and can come bundled with specialized network management software that simplifies network monitoring and troubleshooting.

If your NT machine routes packets over a frame relay interface, connect your NT machine to a DSU/CSU. That connection requires a plug-in V.35 board with RAS drivers. After you connect to the DSU/CSU, you can route packets with RAS as I described in June.

To buy a dedicated router, look to Compatible Systems in Boulder, Colorado. For a simple dial-up connection, I recommend their MicroRouter 900i. For the faster frame relay connection, you'll have to move up to the MicroRouter 1200i (about $800 and $1200 discounted).

Your ISP will recommend another router vendor (call it "Vendor X." Hint: Vendor X is big--really big). My experience with these routers has been tremendously disappointing, starting with the router's functionality: no lights. And there's no easy-to-use, NT-based router management software. You can connect a terminal to the Vendor X router, but you need a separate, nonstandard cable (Compatible Systems' routers come with cables). And Vendor X's router boasts only a 15-pin DIX/AUI Ethernet connector (Compatible Systems' routers have all three Ethernet connector types built in).

By now, I hope we're all connected. Next month, we'll start figuring out how to call each other by name with DHCP. See you then, and keep those emails rolling in.

Contact Info
Compatible Systems * 303-444-9532 or 800-356-0283
Web: http://www.compatible.com