Using Hash-Verify; Using Virtual-Player Type Qss-Streamlet Rate-Map - Juniper MEDIA FLOW CONTROLLER 2.0.4 - ADMINISTRATOR S GUIDE AND CLI Administrator's Manual

Media Flow Controller Configuration Tasks (CLI)

Using hash-verify

Media Flow Controller computes an md-5 hash of an incoming URL by combining a specified
part of the URL along with a pre-shared secret value (configured via Media Flow Controller
CLI). The computed hash digest value is then compared with the hash value provided in the
incoming URL via a pre-specified match query-string-parm (configured via Media Flow
Controller CLI). If a match between the computed and provided hash values is unsuccessful,
then the incoming request is denied.
Example URL showing match query-string-parm h (configured in Media Flow Controller):
http://video.example.com/public/2010/
qwerty.flv?fs=5000&ri=300&rs=1234567&h=<128-bit-md-5-hash>
If Media Flow Controller encounters this URL, it takes the entire URL (shown in blue), until it
encounters the provided match query-string-parm; for example, h (shown in red).
The hash value is then computed by either appending or prefixing to the URL the configured
shared-secret value as specified in the CLI, and comparing the computed value with the
value provided via the match query-string-parm (shown in green).
Example if shared-secret is appended:
Computed hash value = MD5(http://video.example.com/public/2010/
qwerty.flv?fs=5000&ri=300&rs=1234567 + shared-secret)
Example if shared-secret is prefixed:
Computed hash value = MD5(shared-secret + http://video.example.com/public/
2010/qwerty.flv?fs=5000&ri=300&rs=1234567)
Note! The secret key is called a shared-secret key, because the same key is also used by
the browser/video player that generates the request for the object, to compute the hash value
which is present in the pre-specified query parameter for comparison.
Note! Types 1 and 4 virtual-players have a default match query-string-parm of h, this can be
changed in the CLI.

Using virtual-player type qss-streamlet rate-map

Virtual player type qss-streamlet allows you to configure a rate-map to ensure a specified
delivery rate is applied to certain requests. The configuration calls for you to specify a match
<string> to a rate <kbps>; when the request arrives the match <string> is extracted from the
URL and its corresponding rate (in kbps) is used for the delivery rate.
By default, the match string (length must be 2 bytes; for example, 01) is extracted by going to
the end of the URL and skipping 12 Bytes from the end; the value in that location is mapped to
the configured rate in kbps. Example:
http://video.example.com/public/BBB87026/xy_750_1938344/
AC60E15B2A7C4A45AC4C1472E2AC0816_030000003F.flv
In the URL, the value
corresponding assured flow rate (1000Kbps) is applied.
The configured CLI looks like this:
virtual-player my_virtual_player type qss-streamlet
rate-map match 01 rate 300
rate-map match 02 rate 500
rate-map match 03 rate 1000
76 Creating and Configuring Virtual Players (CLI)
03 (12 Bytes from the end of the URL) is extracted, and the
Media Flow Controller Administrator's Guide
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