Content delivery by a network node in a network is optimized. The network node is communicatively coupled between multiple client devices and at least one content service provider. A media streaming service provided by a content service provider is received at the network node over a first unicast link. The service is transmitted from the network node to a first requestor device via a second unicast link. A request from a second requestor device for the service is intercepted by the network node. If it is determined that a multicast optimization threshold has been reached and/or exceeded, the service is transmitted from the network node to the first and second requestor devices using a single multicast link, while the service is received from the content service provider over the first unicast link.