Plateforme Level Extreme
Abonnement
Profil corporatif
Produits & Services
Support
Légal
English
Capibilities of VFP Database
Message
De
19/02/1998 19:33:09
Scott Knight
Human Resources Development Canada
St. John's, Terre-Neuve, Canada
 
Information générale
Forum:
Visual FoxPro
Catégorie:
Client/serveur
Divers
Thread ID:
00079505
Message ID:
00079986
Vues:
62
>>>>We have piloted the Winframe technology and we have found it great for dial-up but we found having multiple users on the same 56k line it seems to bottleneck. We contacted winframe just yesterday and they said the rule of thumb was 15k of bandwidth per user. This would allow us only 3.7 users per site without increasing the bandwidth, which is quite expensive. On a 14.4 modem you almost get the suggested mininum giving the through put you require. FoxPro also builds it's screens differently than other languages which may have some kind of an effect. We thought that Winframe would be our answer but so far we have not had any success with more that 4 users on at the same time. I would be causious jumping into winframe depending on what kind of problem you are trying to solve.
>>>>
>>>>Thanks
>>>>
>>>>
>>>>Scott
>>>
>>>Hi Scott,
>>>
>>>Thanks for the info -- most appreciated. What kind of setup are you working with though? Is your 56K line a WAN link? The setup I am currently looking at testing is a T1 line at head office and, for larger branch offices, a direct 56K gateway to the internet so all WinFrame communication would be TCP/IP. Any thoughts or insight appreciated. TIA
>>
>>Colin,
>>
>>We have piloted 1 office that has Banyan LAN. That LAN in connected to T1 backbone which connects to another office which houses the Winfram server via another 56k line. The application is a VFP app that was written for local use and just basically installed in the NT Winframe box. The install and initial setup just as easy a PC, run the setup program and follow the defaults. The problems start when multiple users access ovr the line. The app runs fine it is just unacceptably slow. We did extensive testing using sniffers etc and determined that every time the mouse moves pixel on the screen a transaction is sent to and from the server. The actual packet size is very small 5 bits but the TCP/IP overhead is about 9 times that. Another problem that caused traffic was the blinking cursor. Every time the cursor blinks on and off a transaction is sent back to the server. Your network setup sounds very similar to mine and the 56k line just did not cut for more than 3 users using th
>>app at the same time. The rule of thumb from Winframe engineers is 15K of bandwidth per user. Every one we bounce the problem off says 15K, no way. I can't speak for other development tools such as VB and Acess, but VFP doesn't work well with winframe. We have yet to determine why ? If you come up with anything else let me know.
>>
>>
>>Scott k
>
>I was just talking to our head network guy and he explained to me how we are setting this all up. We are dealing with an internet provider that covers pretty much all of North America all connected by T3. What we are going to do is connect directly to our ISP with a burstable T1 line at head office and a 56K line at the branches. With this setup we are bypassing all the hop and hub traffic of the phone company. So, if a user in a branch office is running an app on WinFrame the traffic is travelling via 56K line to ISP server, across T3, and down T1 to WinFrame and back.
>
>By the way, the thread "Is VFP Bitmapped" states the reason VFP doesn't work well with WinFrame over phone lines.

Thanks for the info. You may still have this bottleneck problem because the 56k line in the slowest link in the chain. If you have multiple users in that branch office all fighting over that 56k line you can expected hang times with more than 4 users. That's what we found anyway. If you test this and don't feel this bottleneck please let me know ASAP.

Thnaks


Scott k
Précédent
Suivant
Répondre
Fil
Voir

Click here to load this message in the networking platform