Abstract: With the development and popularization of network, the management and monitoring of network traffic is important to keep the network smooth and efficient. It is increasingly critical that an organization secure the system to avoid external hacking and employee abuse of computers in the workplace. This paper study the problem of employee abuse of computers in the workplace and discuss ethical and legal dimensions of the decision facing employers and network administrators regarding whether it is appropriate to monitor the employee's workstation in the organizations. Packet Sniffer is a tool used by network administrators to capture all the packets on the network and monitor the bottlenecks, alarm the irregular behavior, capture passwords and VoIP from any workstation in that network to keep network secured. We give a brief introduction of what is a packet sniffer, its structure, uses and types. Two of the most popular packet sniffing software are discussed and examined; Wireshark and Colasoft Capsa. They are compared according to their features, characteristic behavior, qualitative and quantitative parameters.

Keywords: Packet capture, Traffic analyzer, Network monitoring, Network Sniffing, Network analyzer, Packet sniffer, Wireshark, Colasoft Capsa.