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HELP ME · Guest

One question about Metering Service of DRM10.
How to get 'MeterChallenge' value from client ?

In the document of WMRM10SDK there are any sample code of Metering Service.
One of them is as belows;

'"""""""""""""""""""""""""""""""""""""""""""""""""""""
' Set variables.
'"""""""""""""""""""""""""""""""""""""""""""""""""""""
MeterChallenge = "<Replace with a metering challenge from the client>"
MeterCert = "<Replace with your metering certificate>"
MASPrivateKey = "<Replace with the private key for your service>"
'"""""""""""""""""""""""""""""""""""""""""""""""""""""

Three values are set you see.
I read all documents and understand that 'MeterCert' will be published from
Microsoft.
And 'MASPrivateKey' will be generated from my DRM10 Server.
BUT I could not find how to get 'MeterChallenge' from client ...

Please help me.

Alex · Guest

Once you have a metering cert from MS you can read the metering
challenge from the client using WMDMSDK (part of WMFSDK 9.5). Search
for GenerateMeterChallenge on msdn.microsoft.com . I think that there
is also a nice article that explains it all.

"HELP ME" <HELPME@discussions.microsoft.com> wrote in message news:<25FFF9A9-F255-4DE6-B2D8-078EB6448695@microsoft.com>...

HELP ME · Guest

Thanks Alex :-)

Please allow me one more question.
You said "you can read the metering challenge from the client using WMDMSDK
(part of WMFSDK 9.5)".
The client using WMDMSDK must be original application ?
WindowsMediaPlayer10 don't send "Metering Challenge" value to WMRM10 Server ?

As far as I survey WMP9 don't send "MeteringChallenge" without original
Plug-in of metering service , but WMP10 will send "MeteringChallenge".
If it is correct I want to know HOW to get MeteringChallenge form WMP10.

"Alex" wrote:

Alex · Guest

The documentation is misleading. It makes you believe that WMP is
going to send the metering challenge. In fact your application has to
extract this and send it to your server (or as Microsoft said it to
your "Metering Aggregation Service"). Your application may be a
subscription services plugin in WMP10 or a stand alone application.
On the server you will be able to decrypt the metering challenge
(there is a nice sample in msdn about this) and generate the metering
response.
Then you send the metering response to the client and your client
application will have to call ProcessMeterResponse to reset the
meters.

This works the same way for PC and devices.

The metering is not implemented in WMP9 so everything about meters
applies to WMP10 and WMFSDK 9.5 .

"HELP ME" <HELPME@discussions.microsoft.com> wrote in message news:<D6F86B52-E6E3-4B86-93B1-AE47230F6BC2@microsoft.com>...

HELP ME · Guest

Thanks Alex :-)
Your advise is very help for me !!

I will download WMF9.5SDK and try to make 'Metering Plug-in for WMP10'.

If there is any sample code(VC++?) to Generate 'MeteringChallenge' value ,
please teach me.
To say more if you have already made Metering Plug-in for WMP10 , please
send me as reference.

Thanks

"Alex" wrote:

Alex · Guest

I don't think there is any sample and I cannot give you any source
code I wrote because It does not belong to me.

It is not very complicated to read the meters from the PC.

1. Obtain a metering certificate from MS
2. On the server, when issuing a license, set the MeteringCertificate
property of WMRMRights to the certificate you received from MS
3. Register the license on the client and play the secure file
4. Create a client application that does this:
- CoCreateInstance of IWMDRMDeviceApp
- call IWMDRMDeviceApp::GenerateMeterChallenge and obtain the
challenge string
5. Send the challenge string to the server where you can decrypt it
and read the usage. There is a sample of how to do this. Generate a
metering response string and send it back to the client
6. Call in the client app IWMDRMDeviceApp::ProcessMeterResponse using
the respose you got from server. This will reset the metering data on
the PC

HELP ME · Guest

Hello Alex

Now I am trying to test MeteringService.
Please give me any advice.

"Alex" wrote:

Alex · Guest

"HELP ME" <HELPME@discussions.microsoft.com> wrote in message news:<D8A02598-1579-445C-B087-AFDE855B9EE4@microsoft.com>...

HELP ME · Guest

Hello Alex

Very Very Thanks you for your reply.
Your advice is very useful !!
I will try again :-)

Are you MVP of WindowsMedia??
You are well acquainted with the technology .

Very Thanks :-)

"Alex" wrote:

Dennies Chang · Guest

Thanks Alex,

But when I call IWMDRMDeviceApp->QueryDeviceStatus or
IWMDRMDeviceApp->GenrtateMeterChallenge, the function return
-1072879769, I had WMF SDK, WMDM SDK, should I use any
other SDK to get the correct result? Thanks for your information.

Best Regard.
Dennies Chang.

"Alex" wrote:

exalien · Joined: 22 Sep 2005 Posts: 3

Hey Dennis how did you end up getting a valid return from GenerateMeterChallenge? I've been getting the same error code (-1072879769) and I can't figure out why. I'm basically using the sample code from the Microsoft documentation.

drmNoob · Joined: 16 Nov 2005 Posts: 1