System and method for caching popular content respective of a content strong server in an asymmetrical routing topology

A service delivery apparatus (SDA) for delivering popular content in an asymmetrical network topology, comprising:

• a first network interface to sniff traffic between at least a first portion of a network and at least a second portion of a network;
• a deep-packet-inspection (DPI) unit coupled to the first network interface and configured to identify at least a source of content of the sniffed traffic, the DPI unit further inspecting one or more packets, through the first network interface from the identified source of content, each packet having at least a specific source address and a specific destination address;
• a storage for storing at least information of the content received through the first network interface;
• a second network interface configured to communicate with the at least a first portion of the network and the at least a second portion of the network;
• and
• a processor;
• and
• wherein the processor is configured to cause the SDA to send an instruction to the UN to redirect content requests to the SDA on receiving a request for the content from a user node (UN), the request comprising at least a content identification (CID),
• wherein the processor is configured to send a request to a content source (CS) for the content, the request including the CID upon determination that the downstream data link between the UN and the CS is inaccessible to the SDA.