Pushing data from the server to the client

[DW]

Hi,

Here is my question. I want to push security prices to the desktop from the
server. Whenever there is a new price in the database, the server notifies
the client. How can this be done in the following situations using MS .NET
Winforms on the desktop:

1. Using .NET Web Services on server

2. Using Java Web Services on server

3. Using .NET Remoting on server

Thanks.

- David W.

[RCS]

First thing that comes to mind, is I'd consider having a TcpServer on your
client that listens.. have your server connect and send it a command - like
"UPDATE" when there is a change. When your client recieves that, it hits
your web service or uses remoting. Seems like you could use a
publish/subscribe pattern here too - but *how* is the tricky part. Because I
assume you need real-time - and that's what makes it funny. If you are doing
this on a per-security basis, that is going to be BRUTAL, on the server, on
your app and on the network.

But also, I am willing to bet you are using delayed quotes, because
real-time quotes are super-expensive and difficult to get at programatically
(from my experience) but delayed quotes you can get from anywhere, and if
you are a brokerage firm, you even have a few options no doubt.

If that's the case, why not just have a cache of prices locally and just go
get updates every few minutes? That way, you will always have information on
the client machine, and it's never any older than lastcheck +
originaldelay.. so say if you check every 2 minutes and your original quotes
are delayed 20 minutes, the data is never older than 22 minutes, sometimes
less.??

And as far as Java vs. .NET web services - I had the pleasure recently to
see textbook technology at work - we use a vendor, they wrote a web service
that I didn't have access to yet (because of infrastructure issues). They
gave me the .wsdl file for the web service (which was written in Java). So I
mocked up a facade web service on my side in .NET that had this interface
and wrote to it. I developed to that interface for a couple months and the
consumer was all in .NET (C#)!!

On the day when I could finally access thier web service, I literally just
changed the URL from my facade, to point to them and it worked perfectly
right away, and has continued to work ever since.

So having a .NET or Java web service as your back-end should be completely
invisble to you.

Remoting doesn't sound like a reasonable idea because you'd have to have the
remoting dll on each client machine and the stub on the server. The
connection management of Remoting is almost non-existent, so it's very
difficult to manage "what" your application is doing over the wire or over
in the client app. There is also quite a bit of overhead per connection with
Remoting, so you'd also have a practical limit based on CPU and RAM of your
server..

HTH..
"DW" <dd********@hotmail.com> wrote in message
news:PZ********************@rcn.net...

Hi,

Here is my question. I want to push security prices to the desktop from
the server. Whenever there is a new price in the database, the server
notifies the client. How can this be done in the following situations
using MS .NET Winforms on the desktop:

1. Using .NET Web Services on server

2. Using Java Web Services on server

3. Using .NET Remoting on server

Thanks.

- David W.

[DW]

Are there any good resources in existence that explain how to set up a push
model using .Net Remoting and/or .Net Web Services?

"Raqofella via DotNetMonster.com" <fo***@DotNetMonster.com> wrote in message
news:b3******************************@DotNetMonste r.com...

hey

i was you i would select the first option cause the third option demands
that you are behind your internal network (not firewalls guarded wan, lan)
to make that notification (events/delegates) stuff.

to implement event/delegates stuff with .net remoting or similar ideas for
your webservice and additional info please check these out:

http://www.dotnetmonster.com/Uwe/For...00/Is-there-a-
safer-way-without-using-typeFilterLevel-Full
http://www.dotnetmonster.com/Uwe/For...894/Singleton-
heartbeat-monitoring

a last note: there are third party channel components which permit you to
be able to pass through firewalls, but they are not free as i know...

--
Message posted via http://www.dotnetmonster.com

[DW]

Are there any good resources in existence that explain how to set up a push
model using .Net Remoting and/or .Net Web Services?

"RCS" <rs****@gmail.com> wrote in message
news:VH****************@newssvr33.news.prodigy.com ...

First thing that comes to mind, is I'd consider having a TcpServer on your
client that listens.. have your server connect and send it a command -
like "UPDATE" when there is a change. When your client recieves that, it
hits your web service or uses remoting. Seems like you could use a
publish/subscribe pattern here too - but *how* is the tricky part. Because
I assume you need real-time - and that's what makes it funny. If you are
doing this on a per-security basis, that is going to be BRUTAL, on the
server, on your app and on the network.

But also, I am willing to bet you are using delayed quotes, because
real-time quotes are super-expensive and difficult to get at
programatically (from my experience) but delayed quotes you can get from
anywhere, and if you are a brokerage firm, you even have a few options no
doubt.

If that's the case, why not just have a cache of prices locally and just
go get updates every few minutes? That way, you will always have
information on the client machine, and it's never any older than
lastcheck + originaldelay.. so say if you check every 2 minutes and your
original quotes are delayed 20 minutes, the data is never older than 22
minutes, sometimes less.??

And as far as Java vs. .NET web services - I had the pleasure recently to
see textbook technology at work - we use a vendor, they wrote a web
service that I didn't have access to yet (because of infrastructure
issues). They gave me the .wsdl file for the web service (which was
written in Java). So I mocked up a facade web service on my side in .NET
that had this interface and wrote to it. I developed to that interface for
a couple months and the consumer was all in .NET (C#)!!

On the day when I could finally access thier web service, I literally just
changed the URL from my facade, to point to them and it worked perfectly
right away, and has continued to work ever since.

So having a .NET or Java web service as your back-end should be completely
invisble to you.

Remoting doesn't sound like a reasonable idea because you'd have to have
the remoting dll on each client machine and the stub on the server. The
connection management of Remoting is almost non-existent, so it's very
difficult to manage "what" your application is doing over the wire or over
in the client app. There is also quite a bit of overhead per connection
with Remoting, so you'd also have a practical limit based on CPU and RAM
of your server..

HTH..
"DW" <dd********@hotmail.com> wrote in message
news:PZ********************@rcn.net...

Hi,

Here is my question. I want to push security prices to the desktop from
the server. Whenever there is a new price in the database, the server
notifies the client. How can this be done in the following situations
using MS .NET Winforms on the desktop:

1. Using .NET Web Services on server

2. Using Java Web Services on server

3. Using .NET Remoting on server

Thanks.

- David W.

[DW]

RCS,

Can you "subscribe" to a Java webservice using a delegate and a callback and
have data pushed from the Java webservice to your client? Thanks.

- David

"RCS" <rs****@gmail.com> wrote in message
news:VH****************@newssvr33.news.prodigy.com ...

First thing that comes to mind, is I'd consider having a TcpServer on your
client that listens.. have your server connect and send it a command -
like "UPDATE" when there is a change. When your client recieves that, it
hits your web service or uses remoting. Seems like you could use a
publish/subscribe pattern here too - but *how* is the tricky part. Because
I assume you need real-time - and that's what makes it funny. If you are
doing this on a per-security basis, that is going to be BRUTAL, on the
server, on your app and on the network.

But also, I am willing to bet you are using delayed quotes, because
real-time quotes are super-expensive and difficult to get at
programatically (from my experience) but delayed quotes you can get from
anywhere, and if you are a brokerage firm, you even have a few options no
doubt.

If that's the case, why not just have a cache of prices locally and just
go get updates every few minutes? That way, you will always have
information on the client machine, and it's never any older than
lastcheck + originaldelay.. so say if you check every 2 minutes and your
original quotes are delayed 20 minutes, the data is never older than 22
minutes, sometimes less.??

And as far as Java vs. .NET web services - I had the pleasure recently to
see textbook technology at work - we use a vendor, they wrote a web
service that I didn't have access to yet (because of infrastructure
issues). They gave me the .wsdl file for the web service (which was
written in Java). So I mocked up a facade web service on my side in .NET
that had this interface and wrote to it. I developed to that interface for
a couple months and the consumer was all in .NET (C#)!!

On the day when I could finally access thier web service, I literally just
changed the URL from my facade, to point to them and it worked perfectly
right away, and has continued to work ever since.

So having a .NET or Java web service as your back-end should be completely
invisble to you.

Remoting doesn't sound like a reasonable idea because you'd have to have
the remoting dll on each client machine and the stub on the server. The
connection management of Remoting is almost non-existent, so it's very
difficult to manage "what" your application is doing over the wire or over
in the client app. There is also quite a bit of overhead per connection
with Remoting, so you'd also have a practical limit based on CPU and RAM
of your server..

HTH..
"DW" <dd********@hotmail.com> wrote in message
news:PZ********************@rcn.net...

Hi,

Here is my question. I want to push security prices to the desktop from
the server. Whenever there is a new price in the database, the server
notifies the client. How can this be done in the following situations
using MS .NET Winforms on the desktop:

1. Using .NET Web Services on server

2. Using Java Web Services on server

3. Using .NET Remoting on server

Thanks.

- David W.

[RCS]

Not as far as I know. Whenever I've needed that (and that's twice) - I
created a TcpClient/TcpServer to handle this.

"DW" <dd********@hotmail.com> wrote in message
news:ge********************@rcn.net...

Are there any good resources in existence that explain how to set up a
push
model using .Net Remoting and/or .Net Web Services?

"RCS" <rs****@gmail.com> wrote in message
news:VH****************@newssvr33.news.prodigy.com ...

First thing that comes to mind, is I'd consider having a TcpServer on
your client that listens.. have your server connect and send it a
command - like "UPDATE" when there is a change. When your client recieves
that, it hits your web service or uses remoting. Seems like you could use
a publish/subscribe pattern here too - but *how* is the tricky part.
Because I assume you need real-time - and that's what makes it funny. If
you are doing this on a per-security basis, that is going to be BRUTAL,
on the server, on your app and on the network.

But also, I am willing to bet you are using delayed quotes, because
real-time quotes are super-expensive and difficult to get at
programatically (from my experience) but delayed quotes you can get from
anywhere, and if you are a brokerage firm, you even have a few options no
doubt.

If that's the case, why not just have a cache of prices locally and just
go get updates every few minutes? That way, you will always have
information on the client machine, and it's never any older than
lastcheck + originaldelay.. so say if you check every 2 minutes and your
original quotes are delayed 20 minutes, the data is never older than 22
minutes, sometimes less.??

And as far as Java vs. .NET web services - I had the pleasure recently to
see textbook technology at work - we use a vendor, they wrote a web
service that I didn't have access to yet (because of infrastructure
issues). They gave me the .wsdl file for the web service (which was
written in Java). So I mocked up a facade web service on my side in .NET
that had this interface and wrote to it. I developed to that interface
for a couple months and the consumer was all in .NET (C#)!!

On the day when I could finally access thier web service, I literally
just changed the URL from my facade, to point to them and it worked
perfectly right away, and has continued to work ever since.

So having a .NET or Java web service as your back-end should be
completely invisble to you.

Remoting doesn't sound like a reasonable idea because you'd have to have
the remoting dll on each client machine and the stub on the server. The
connection management of Remoting is almost non-existent, so it's very
difficult to manage "what" your application is doing over the wire or
over in the client app. There is also quite a bit of overhead per
connection with Remoting, so you'd also have a practical limit based on
CPU and RAM of your server..

HTH..
"DW" <dd********@hotmail.com> wrote in message
news:PZ********************@rcn.net...

Hi,

Here is my question. I want to push security prices to the desktop from
the server. Whenever there is a new price in the database, the server
notifies the client. How can this be done in the following situations
using MS .NET Winforms on the desktop:

1. Using .NET Web Services on server

2. Using Java Web Services on server

3. Using .NET Remoting on server

Thanks.

- David W.

[RCS]

I don't think this will be fundamentally work - mainly because http is
connectionless and assumes no connection other than right at the moment of a
request. So I believe that you can't have a http-based "push" technology,
it'd have to be your own version (like the other "push" technologies have
been).

You COULD completely do this in sockets (.net network libraries), just not
with HTTP I believe

"DW" <dd********@hotmail.com> wrote in message
news:4N********************@rcn.net...

RCS,

Can you "subscribe" to a Java webservice using a delegate and a callback
and have data pushed from the Java webservice to your client? Thanks.

- David

"RCS" <rs****@gmail.com> wrote in message
news:VH****************@newssvr33.news.prodigy.com ...

First thing that comes to mind, is I'd consider having a TcpServer on
your client that listens.. have your server connect and send it a
command - like "UPDATE" when there is a change. When your client recieves
that, it hits your web service or uses remoting. Seems like you could use
a publish/subscribe pattern here too - but *how* is the tricky part.
Because I assume you need real-time - and that's what makes it funny. If
you are doing this on a per-security basis, that is going to be BRUTAL,
on the server, on your app and on the network.

But also, I am willing to bet you are using delayed quotes, because
real-time quotes are super-expensive and difficult to get at
programatically (from my experience) but delayed quotes you can get from
anywhere, and if you are a brokerage firm, you even have a few options no
doubt.

If that's the case, why not just have a cache of prices locally and just
go get updates every few minutes? That way, you will always have
information on the client machine, and it's never any older than
lastcheck + originaldelay.. so say if you check every 2 minutes and your
original quotes are delayed 20 minutes, the data is never older than 22
minutes, sometimes less.??

And as far as Java vs. .NET web services - I had the pleasure recently to
see textbook technology at work - we use a vendor, they wrote a web
service that I didn't have access to yet (because of infrastructure
issues). They gave me the .wsdl file for the web service (which was
written in Java). So I mocked up a facade web service on my side in .NET
that had this interface and wrote to it. I developed to that interface
for a couple months and the consumer was all in .NET (C#)!!

On the day when I could finally access thier web service, I literally
just changed the URL from my facade, to point to them and it worked
perfectly right away, and has continued to work ever since.

So having a .NET or Java web service as your back-end should be
completely invisble to you.

Remoting doesn't sound like a reasonable idea because you'd have to have
the remoting dll on each client machine and the stub on the server. The
connection management of Remoting is almost non-existent, so it's very
difficult to manage "what" your application is doing over the wire or
over in the client app. There is also quite a bit of overhead per
connection with Remoting, so you'd also have a practical limit based on
CPU and RAM of your server..

HTH..
"DW" <dd********@hotmail.com> wrote in message
news:PZ********************@rcn.net...

Hi,

Here is my question. I want to push security prices to the desktop from
the server. Whenever there is a new price in the database, the server
notifies the client. How can this be done in the following situations
using MS .NET Winforms on the desktop:

1. Using .NET Web Services on server

2. Using Java Web Services on server

3. Using .NET Remoting on server

Thanks.

- David W.

[William Stacey [MVP]]

You could have WSE service running on the client that has one method
UpdatePrices(someXmlDoc). The server could then call (using WSE) all the
clients. The clients would need to subscribe to the service before hand and
the server would need to maintain some table of client endpoints. Another
option would be to "ping" the client to pull. So instead of pushing the
data first, just call a Ping() or Alert() method on the client and close.
This kicks off the client to get the new prices from the WSE service on the
server side. This may allow easier security integration as you "flip" it
back to normal pattern where the client must authenticate to the server
using UT or SCT tokens before calling protected methods such as
GetNewPrices(). If security is not an issue, then may not matter which way,
but I think I like the second way better as it gives you the option to
include server authentication using std WS-Security or
WS-SecureConversation.

--
William Stacey, MVP
http://mvp.support.microsoft.com

"DW" <dd********@hotmail.com> wrote in message
news:PZ********************@rcn.net...

Hi,

Here is my question. I want to push security prices to the desktop from the server. Whenever there is a new price in the database, the server notifies the client. How can this be done in the following situations using MS ..NET Winforms on the desktop:

1. Using .NET Web Services on server

2. Using Java Web Services on server

3. Using .NET Remoting on server

Thanks.

- David W.