Network topology and operation

Network topology

ContentDirector uses network connectivity to distribute content. The connections can be on VPNs on intranets and the Internet. The core application machine communicates with the ContentDirector agents using a TCP connection and HTTP.

Each ContentDirector agent is a member of a transport group. The subset of the overall network topology that contains the transport group is call the network segment (netseg).

Network operation and links

Before you begin to deploy ContentDirector, you should determine the following:

Verify that the network is running and stable
Verify that you have the correct IP address for the core application machine.
Note
If you have a NAT based firewall, the NATed IP address must be used.
If you have not done so in the planning phase, determine which routers in a given network segment are multicast enabled. Multicast enabled routers are necessary for multicast transport (group leader to group member) across routers. This is essential for transport via satellite. If routers are not multicast enabled, only unicast transport can be used across routers.
If you want a transport group to include devices on both sides of a unicast router, you can only designate devices on one side of the router as group leaders (assigned or candidate). If CDAs on both sides of the unicast router are designated as group leaders, two active group leaders will be elected. In effect, this creates two transport groups.
Caution
Do not remove the primary network interface card from a NetCache appliance and use it as the primary network interface card in another NetCache appliance. Doing so can cause the CDA to malfunction.