Scenario: Multicast support for transmission over a satellite link

About this scenario

This scenario describes a deployment for a company with multiple offices across the world. NetCache appliances are configured for multicast input.

Organization's requirements

The company's requirements are as follows:

Reserve its primary data link for business-critical traffic
Use multicast transmission over a satellite link to send non-business-critical traffic, such as streaming media of company meetings and training videos
Use of a satellite link eliminates the possibility of non-business critical traffic causing network congestion, which would interrupt company business and reduce the quality of streaming media. Use of a satellite link for non-business-critical traffic will also reduce costs because it is less expensive than the primary data link that the company uses.

Deployment illustrated

The following illustration shows a multicast broadcast over a satellite link.

Assume that the corporate headquarters is broadcasting a live corporate meeting. A camera in the headquarters records the meeting and transmits it to a third-party vendor to encode the stream and upload the stream to a satellite link for transmission over multicast. The corporate offices in France and Germany download the stream from the satellite so that their employees can view the corporate meeting live.

Clients at the U.S. site could view the stream through the corporate LAN, or the stream could be downloaded from the satellite.

Configuration of the NetCache appliances in France and Germany is set up as follows:

The NetCache appliances in France and Germany are configured for multicast input so that they can receive multicast transmissions from the multicast-enabled router that downloads the stream from the satellite link.
The NetCache appliances in France and Germany are also configured for multicast output. The reason is that each corporate site is multicast-enabled. By configuring the NetCache appliances for multicast out, the appliances can pass streams to the next-hop routers in the corporation without splitting the stream. Each router determines whether the stream should be split at that point.
Note
Typically, communication over the satellite is asymmetric, that is, only from the satellite transmission point to the destination at the end of the satellite link. Requests from France and Germany for the live broadcast must be sent over the terrestrial backchannel link.