Pre-Stage On-Demand Assets; Initiate Smoothflow Processing For On-Demand Assets - Juniper MEDIA FLOW CONTROLLER 2.0.4 - ADMINISTRATOR S GUIDE AND CLI Administrator's Manual

Media Flow Controller Administrator's Guide
The AFR Threshold value can be specified in the Asset Description File (.dat), if using the On-
Demand Publishing scheme (or using a Python script if using encoding.com). It's unit is kbps.
Do not specify this value in the Smoothflow Control File; it automatically picks up the value
from the Asset Description File (.dat) when SmoothFlow processing is initiated.
The rationale behind providing the AFR value is empirical. For example, if there are 5 profiles
each at (200, 400, 600, 800 and 1000kbps). We recommend you set the value for AFR
Threshold to be greater than 1/2 the bit rate of the highest profile. In this case you can set it to
any value > 500 kbps. This accelerates the switching speed from lower to higher profiles. In
this example, the player will switch from 200 to 400 to 600 very quickly and will then slow down
in terms of switching to 800 and 1000kbps. Typically, content providers do not like players to
very quickly switch to the highest bit rate because this increases their bandwidth costs. If a
provider desires that the switching to the highest bitrate happens faster, then set the AFR
Threshold value to be equal to the highest available rate (for example, 1000kbps)

Pre-Stage On-Demand Assets

The Asset Description file provides Media Flow Controller with the information it needs to
SmoothFlow process and serve the encoded videos. Typically, it is placed on your Web server
with the media assets; however it can be kept on any defined origin server in the namespace
you use. A few options to stage the assets are as follows:
•
Place it on your Web server, define that Web server as an origin server in the SmoothFlow
namespace, use that namespace's defined uri-prefix in your SmoothFlow processing
request.
•
FTP it to your Media Flow Controller origin server; if your SmoothFlow processing request
is to that Media Flow Controller, it looks for the file locally.
Tip! Typically, assets are pre-staged to an origin server with non-volatile storage (NFS, RAID,
or NAS); however, you may pre-stage assets to an edge cache. In that case, be sure to also
pre-stage them to the origin server as well, since edge caches are typically configured to
delete files after a short time (cache expiry).

Initiate SmoothFlow Processing for On-Demand Assets

After the SmoothFlow assets and the Asset Description file are created and pre-staged to
origin, and Media Flow Controller is configured, you send a request to Media Flow Controller
to initiate SmoothFlow processing. After the files are fetched, SmoothFlow builds the
SmoothFlow Control file (see
with asset information.
A processing request with SmoothFlow state sf=4, of the form shown, must be sent to initiate
SmoothFlow processing. You can do this through a browser, or use wget or curl.
http://<name_of_mfc>/sf/<name_of_MediaAssetDescription_file>.dat?sf=4
Media Flow Controller internally decomposes this request into the relevant configured
namespace and, if the virtual player type assigned to that namespace matches the
SmoothFlow player type (Type 4), then, by recognizing the state of sf = 4, Media Flow
Controller initiates SmoothFlow processing for the asset referenced in the retrieved Asset
Description file. SmoothFlow processing is only done when a SmoothFlow process request
from the publisher, in the form given above, is received, or when there is a cache miss in real
time. If the pre-staging is to an attached NFS library, then the publisher can see the listing of
About SmoothFlow Control
SmoothFlow Deployment
File) that is sent to the client player
Creating On-Demand Assets 265