Deep Packet Inspection using Ternary Content Addressable Memory

With the increasing internet service complexity, providing secured quality service has become a major concern. In the earlier systems, data was believed to be safer on internet without being intercepted. Now these internet vulnerabilities cannot be ignored as these weaknesses are used by many to carry out malicious activities. In order to tackle these problems, internet service providers are trying to find better options. One such technique gaining popularity in the recent decade is Deep Packet Inspection (DPI), which can be provided using software or hardware methods. It is reported that hardware is providing better solution than software. In this review article, we have introduced one such hardware, Ternary Content Addressable Memory (TCAM), which could perform complete packet inspection (packet header and payload inspection). In the first section, we have focused on evolution of packet filtering system. Later the discussion is divided into two parts: (i) packet classification using TCAM, and (ii) payload inspection (pattern matching and regular expression) using TCAM.