Board index » delphi » wi-fi problem

wi-fi problem


2005-07-30 02:57:24 AM
delphi76
Hi,
I made a program (db based ) that works in a lan enviroment ( client server,
firebird backend ), the program works fine, but we made an extension of the
lan with 2 access points. I already check the wifi configuration and
everything it is working fine ( i made tests sending 5 megs files ), so the
problem is the application.
(the server is here) lan1 <--->accesspoint1 <----->accesspoint2 (works like
bridge)<--->lan2
The application in the lan2 is extremely slow
Any advice to accelerate?
Thanks
Marcelo
 
 

Re:wi-fi problem

Marcelo Villegas writes:
...
Quote
(the server is here) lan1 <--->accesspoint1 <----->accesspoint2
(works like bridge)<--->lan2

The application in the lan2 is extremely slow

Any advice to accelerate?
The db system seems to be a little chatty. The latency of WLAN connections
is very high compared to wired LAN. And if there is much conversation
between client and server, you have to wait.
Ralf
 

Re:wi-fi problem

Marcelo Villegas writes:
Quote
I made a program (db based ) that works in a lan enviroment ( client
server, firebird backend ), the program works fine, but <snip>
(the server is here) lan1 <--->accesspoint1 <----->accesspoint2 (works
like bridge)<--->lan2

The application in the lan2 is extremely slow
In *my* experience, client server is not suited for wireless networks. We
had several client server Oracle based applications. They all worked fine
over the LAN, whether 16Mbps Token Ring, or 10 or 100 Mbps Ethernet. Once
we tried accessing the server over a wireless microwave network (not
802.11, supposedly faster throughput), the Oracle client intermittently
lost connection and started causing errors in the application.
Introducing a third tier solved the problem - the database talked to the
middle tier all on a LAN, and everything else talked TCP/IP to the middle
app. The middle app can be as simple as just proxing your datasets for you.
Midas/DataSnap (Delphi Enterprise & higher) can do this, or kbmMW
(www.components4developers.com), the tool we used was supremely
easy, but we did it a while ago, Asta, from www.astatech.com .
-Brion
 

Re:wi-fi problem

Brion L. Webster writes:
Quote

Introducing a third tier solved the problem - the database talked to
the middle tier all on a LAN, and everything else talked TCP/IP to
the middle app. The middle app can be as simple as just proxing your
datasets for you.

Midas/DataSnap (Delphi Enterprise & higher) can do this, or kbmMW
(www.components4developers.com), the tool we used was
supremely easy, but we did it a while ago, Asta, from
www.astatech.com .
Dont forget to mention Remobjects www.remobjects.com the most complete
and featured IMHO.
Donald
 

Re:wi-fi problem

Donald Shimoda writes:
Quote
Dont forget to mention Remobjects www.remobjects.com the most complete
and featured IMHO.
I've heard very good things about RemObjects, but I don't have any
personal experience with any of their projects (that I remember). I used
to remember to mention them, with that caveat.
Nowadays they're kind of tarnished in my mental image for reasons that are
*totally* nothing to do with the original project, so I tend to forget
they're still out there.
-Brion
 

Re:wi-fi problem

Brion L. Webster writes:
Quote
In my experience, client server is not suited for wireless networks.
tinyurl.com/7t7bc
--
John Kaster blogs.borland.com/johnk
Features and bugs: qc.borland.com
Get source: cc.borland.com
If it is not here, it is not happening: ec.borland.com
 

Re:wi-fi problem

Hi Marcelo,
Quote
(the server is here) lan1 <--->accesspoint1 <----->accesspoint2 (works like
bridge)<--->lan2

The application in the lan2 is extremely slow

Any advice to accelerate?
It may be the data-access, trying to "talk" to the server too often.
What data-access techniques are you using?
Apart from going multi-tier, have you considered / tried a disconnected
approach (using dbExpress in Win32 or ADO.NET/BDP in .NET for example?).
That might also reduce chatting enough to result in a workable
solution...
Quote
Marcelo
Groetjes,
Bob Swart (aka Dr.Bob - www.DrBob42.com)
--
Bob Swart Training & Consultancy (eBob42) - Borland Technology Partner
Delphi 2005 PDF manuals available from www.drbob42.com/training
 

Re:wi-fi problem

"Bob Swart" wrote
Quote
Hi Marcelo,

>The application in the lan2 is extremely slow
>
>Any advice to accelerate?

It may be the data-access, trying to "talk" to the server too often.
What data-access techniques are you using?
Apart from going multi-tier, have you considered / tried a disconnected
approach (using dbExpress in Win32 or ADO.NET/BDP in .NET for example?).
That might also reduce chatting enough to result in a workable
solution...
Yet another viable solution for Win32 is ADO (aka dbGo) using it is disconnected
recordset feature. When doing this type programming my mantra is connect as
seldom as possible and disconnect early and often. ADO fully supports connection
pooling which is a must to speed up traffic.
I would advise anyone wanting to know how best to use ADO get a copy of David
Sceppa's book "Programming ADO". For every developer who's uttered, "I wish I
knew that before I started writing all this code!" this book is your guide to
ADO.
 

Re:wi-fi problem

Angra Mainyu writes:
Quote
David
Sceppa's book "Programming ADO"
David writes good books, from the two I have seen so far.
--
John Kaster blogs.borland.com/johnk
Features and bugs: qc.borland.com
Get source: cc.borland.com
If it is not here, it is not happening: ec.borland.com
 

Re:wi-fi problem

"John Kaster (Borland)" wrote
Quote
Angra Mainyu writes:

>David Sceppa's book "Programming ADO"

David writes good books, from the two I have seen so far.
Yeah, so good that one could almost forgive him for being a Visual Basic kinda
guy.<g>
 

Re:wi-fi problem

Angra Mainyu writes:
Quote
one could almost forgive him for being a Visual Basic kinda
guy
That just makes his books all that more impressive ;)
--
John Kaster blogs.borland.com/johnk
Features and bugs: qc.borland.com
Get source: cc.borland.com
If it is not here, it is not happening: ec.borland.com