A network device may receive user datagram protocol (UDP) packets associated with an internet protocol (IP) session. The network device may apply a first firewall filter by setting one or more bits of each UDP packet to particular bit values to allow each UDP packet to be identified in association with the first firewall filter. The network device may update, each time a UDP packet is received, a first packet counter to account for a total number of UDP packets to which the first firewall filter has been applied. The network device may provide each UDP packet to another network device. The other network device may update a second packet counter. The network device and the other network device may provide the first packet counter and the second packet counter to a server device to cause the server device to determine packet loss information for the IP session.