Content-Centric Networking/Named Data Networking (CCN/NDN) architecture introduces a novel paradigm for the future of the Internet by moving the current system to cutting-edge network protocols. Generally, the main goals of CCN/NDN are to improve the traditional network operations by having devices that are aware of content s name, to route the decisions that are taken based on the content s name of the consumers requests. Despite the numerous advantages out of this shift, hardware challenges, including Pending Interest Table (PIT) is still existing in respect to CCN/NDN implementation in terms of memory that is fast in time accessing and a large packet storing. In addition, designing, implementing, and evaluating a fast and enough PIT with higher capacity is certainly another issue in respect to both packet processing and router storage. Furthermore, existing memory technology that is deployed in in PIT, such as DRAM and SRAM, is presenting further limitation. Therefore, PIT should be able to serve a very large number of Interest (scalability). Significant works have been presented by several researchers concerning
the scalability of PIT, in accommodating more interest; however, there are remaining possibilities for more improvement in such a context. This paper aims to classify an extensive and critical concerning PIT implementation in a concise manner. Then identifying their strength and weaknesses and underline the necessary requirements for better PIT improvement in terms of scalability.