James is working as a Network Administrator in a reputed company situated in California.

James should use the Wireshark filter icmp.type==8 or icmp.type==0 to detect a PING sweep attack. This filter will capture both ICMP echo requests and echo replies, which are used in PING sweeps to discover active hosts on a network. When conducting a PING sweep, an attacker sends ICMP echo requests (type 8) to multiple hosts and listens for echo replies (type 0). By monitoring for both types, James can effectively identify a PING sweep attack.

References: The use of this filter for detecting PING sweeps is documented in various network security resources, including the InfosecMatter guide on detecting network attacks with Wireshark1, which specifically lists icmp.type==8 or icmp.type==0 as the filter for ICMP ping sweeps. This approach is consistent with standard practices for network monitoring and intrusion detection.