Pros: It's fast, fast, fast. Setup is simple. Promises to be cost effective. Cons: High latency. Will be priced for companies that want to connect at least 100 sites. Contact info: Hughes Network Systems, Germantown, Md. (301) 428- 5500 Web site Contact Mark Gibbs

By Mark Gibbs
IntraNet, 5/19/97

"Three months! You're kidding!" This cry is commonly heard in Los Angeles, New York and most other North American metropolitan areas from IT managers trying to get high-speed connections for Internet or intranet access.

A new service from Hughes Network Systems, Inc. (HNS) could considerably shorten that waiting period. The service, called DirecPC Commercial, is handled by satellite-based connections.

DirecPC Commercial builds on the Personal Earth Station (PES) very small aperture terminal system HNS has been offering since 1986 to handle voice, video and LAN traffic. The PES system provides high-speed communications services from a customer premises via satellite to an HNS operations center or hub. DirecPC Commercial adds much higher bandwidth IP transport to the HNS satellite service portfolio.

In the U.S., the HNS network consists of three company-owned geosynchronous satellites. HNS also has relationships with other satellite service operators so it can provide seamless, worldwide coverage.

DirecPC Commercial is the industrial-strength version of DirecPC, a consumer-oriented Internet access product. With DirecPC, requests are sent via a local Internet service provider and responses received over the satellite. With DirecPC Commercial, data is sent (the uplink) and received (downlink) over the satellite connection.

DirecPC and DirecPC Commercial use IP tunneling technology. The DirecPC software, which DirecPC Commercial uses too, appears as an IP gateway to the local computer. The software actually creates a data "pipe" through which all packets to the HNS network are routed.

When accessing a service at an IP address via your local gateway, your request is sent down the IP tunnel (either over your dial-up link to your ISP or via satellite) to the HNS hub, where it is handled by a proxy server and sent to its destination. The response passes through the proxy server and is sent back to you via the satellite link.

With DirecPC Commercial, you can set up permanent virtual circuits (PVC) or switched virtual circuits (SVC) supporting committed information rates allocated in 64K bit/sec portions. Alternatively, you could opt for burst-mode connections that use whatever bandwidth is available up to a maximum of 24M bit/sec.

Intranets in the sky

The DirecPC Commercial service is delivered through a PES at each site. The PES consists of a 1.0-, 1.2- or 1.8-meter dish, the size of which depends on the local signal strength - less signal, more dish - and the data rate - more data, more dish. The dish, because of its small size, can be held in place with ballast.

The dish has a radio frequency (RF) unit on it that sends and receives signals. The outdoor unit (ODU) is this transceiver mounted on the dish and connected via a coax cable to the indoor unit (IDU). The IDU is a box that provides the interface between a computer and the ODU.

HNS contractors install the dish and IDU. For my installation, they only made one mistake: They routed the coax cable from the ODU to the IDU through a pocket door. I just realized this a couple of days ago when I tried to close the door. To be fair, I must point out that pocket doors aren't common in business premises so it is a reasonable mistake.

The IDU's output is via another RF cable that goes to a PCI Plug and Play card in a computer running Windows 95 or Windows NT. The card provides the high-speed data transport - the downlink - into your network.

The standard satellite downlink data rates are 128K and 512K bit/sec. DirecPC Commercial starts at 3M bit/sec and can be increased to an awesome 24M bit/sec (see "PRODUCT CAPSULE").

When you send data, the PC connects to the IDU via a serial, Ethernet or token-ring port. The IDU sends the signal to the ODU which, in turn, relays it to the satellite. Using a serial port effectively limits uplink data rates to a maximum of 115K bit/sec. With Ethernet and token-ring, data can be transmitted to the satellite at up to 256K bit/sec.

Installing and configuring the PCI card is straightforward. To configure the HNS software, you set up the IP addresses for the IP tunnel and put in other information such as SLIP/PPP login parameters. You then need to configure Windows for the IP address allocated to your PC on the HNS network as well as the address of the HNS gateway and Domain Naming System server and your host name and domain for the DirecPC Commercial interface.

To establish the encryption keys that will be used to secure data transmissions, you connect to the HNS data center by conventional modem. Once you have automatically downloaded your key from HNS and it has registered your card's ID, you have to wait up to 45 minutes for the system to accept data transmissions. Typically this is more like 20 minutes, and a planned improvement will reduce the wait time to about five minutes.

HNS doesn't mention it in the documentation, but I recommend backing up the DirecPC Commercial control files. Otherwise, if those files are corrupted or erased, you'll have to go through the initialization process again.

A dishy connection

The minimum latencies from your computer to the HNS hub and to Internet sites are around 400 msec and 900 msec, respectively. That's a bit different than the typical Internet access latencies from 200 to 300 msec experienced while using dial-up services.

With interactive services such as Web browsers and File Transfer Protocol sessions, the satellite-induced latency produces a short but noticeable pause. The delay while using character-oriented services such as telnet is positively uncomfortable. However, once you've got access, the data transfer speed is so fast that when, for example, a Web page does appear, it typically pops up all at once - an unnerving but pleasing performance when you're dealing with a page loaded with graphics and Java applets.

Services and pricing

At press time, HNS was still building its price list for DirecPC Commercial, but the price promises to be affordable.

Latency aside, the performance is terrific and the service is reliable.