Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Hughes Directway Internet Satellite

Status
Not open for further replies.

mimosa

Computer
Nov 29, 2001
1
I'm considering purchasing the Directway Satellite for high-speed internet access. DSL, ISDN and cable modems are not option for me at this time.

I've searched the web looking for positive feedback about the satellite technology and find that a lot of people are very dissatisfied with both the speed of the service and more importantly, the support.

Most of these people are using DirecPC or Starband. Does anyone have any experience with the new Directway satellite offered through Earthlink?
 
Replies continue below

Recommended for you

Hi,

Just found this thread.

I have been fooling with our install of Directway for 4 months now.

I have the dynamic ip version. The DW modems are connected to a W2k box running ICS.

I have several W2k and WXP clients on the lan.

I have them all set to get the ip automatically.

To get consistent DNS (so mail worksmost of the time) I have to specify the DNS on each client.

The problem that has eluded me is client access to secure web sites.
 
You can specify the DNS on a server in Win2K server box. I have never used ICS and do not know how to set it up there. Somewhere in the DHCP psuedo-server there should be an option for that, but I really don't know.

I had to switch back to a DW4000 box. The 4020 would not work in my environment. I think the problem was with Skycasters and their lack of realy knowledge, but I am in a business environment and *need* my connectivity!

ANyway, I am running the service through a win2K Pro box with Sygate office network without DHCP. I have a 28 port network with access to it, although only 2 or 3 users are ever on the internet at one time.

All setting are handled by my Win2K Server through DHCP..including DNS servers and gateway settings.


Eric
 
Do you know of anyone who will resell wild blue sateiilte in the memphis indiana area? The Josh Hutchinson
 
I use Direcway as my ISP, through HighSpeedSat as a reseller - . Overall, it isn't any more or less reliable than residential broadband cable. Latency is the worst part about it -- usually around 700msec, compared to ~5msec I've experienced on some good T1s.

Where I am located (Montenegro, Europe), the weather has to get very bad to cause a service interruption. I've had the service for 2.5 years, and have had weather related problems on two occasions ... only for a couple of hours each.

Reseller customers are typically first in line to get product upgrades such as Direcway 4020 units or Direcway 6000 units. I've got a 4020 unit, and am pretty happy with it. Beats dial-up!
 
I have heard lots of issues with VPN problems using true satellite 2-way communications. Part is due to some of the issues mentioned above (pseudo-networks, no static IP capability etc.) The other issue is latency and unfortunately god and our choice of planet are to blame. The satellites used by the system are geostationary (which allows you to point once a dish stuck to your house toward the satellite parking place on the equatorial plane and out 22,300 miles from the point directly below the satellite).

The delay depending on your lattitude can be over 4*22,300/186,000 or about 1/2 second assuming no processing delays. The reason is when you click your mouse for an http request it goes into your PC -- gets formatted with data and shot out your dish up to the satellite then routed possibly to another satellite (via space crosslink which adds additional delay) then down to the POP gateway. We are up to two 22,300 mile segments now. Then the server processing the http request now must get the info you asked for, format the data and blast it back up to a satellite that again may need to crosslink to yet another satellite and then process the data (spaceway constellation modulates and demodulates the data on board the satellite to allow for switching in space). Finally the last satellite blasts the signal down to your outside dish which is now four 22,300 segments. Divide this by the speed of light and you have a lower bound for the delay due to the distance of the satellite(s) alone.

Add more delay for the TCP/IP protocol and you can easily get into a second or more delay. A lot of hardware may timeout if the delays get much bigger than a second. If a bit error occurs after all the processing that can't be corrected by coding the data, then the data must be resent which then adds another second to the time so now we are up to near two seconds to get a bit that was requested as part of a binary file transfer for example.

For voice and video bit errors are acceptable, for file transfer (sending an executable program for example) bit errors can't be tolerated because the application will likely break. This helps making fewer "hops" to the satellite for time-critical data if some errors can be tolerated (voice sounds ok, video looks ok). However imagine a phone call where a half second elapses between you ending a sentence and the other guy hears it--you'd be stepping all over each other constantly making the communication mode to be more of a "walkie-talkie" than a full-duplex phone.

To cut latency a lower MEO or NEO constellation could be used but you would need a tracking antenna or much more powerful satellites with enormous dishes/arrays to process weak signals that are sent throug omnidirectional antennas rather than the tightly focused parabolic dish. You typically have to drop data rate when the link cannot support communications at a higher data rate.

Hey kj_95376--can't you get cable?

Until Direcway can deliver >1 Mbps per household for <$50 a month I think they are fucked. Considering a satellite costs like $200-$300 MILLION to design build and launch (and god knows how much per year to operate and keep healthy) and they only live about 7 - 10 years and realistically the total transmission bandwidth is probably < 1 GHz or so. If you got 1 bit/sec per Hz of satellite bandwidth that means only 1000 Users that are getting 1 Mbps (maybe 5000 using loading models and oversubscription) I don't see how the thing can ever really be profitable -- lets say we have 5000 users who pay $50/month -- I get about $3M / year revenue how will that ever cover the hundreds of millions of $$$ it cost to put the damn thing there in the first place????? Suppose you get 6 bits/sec per Hz of satellite bandwidth (64 QAM?) then we are up to $18M / year which is still way to little revenue so how is the cost made up without ripping off someone??

Inquiring minds want to know.

 
Status
Not open for further replies.

Part and Inventory Search

Sponsor