In practical applications, firewalking is similar to tracerouting and works by sending into the firewall TCP or UDP packets that have a TTL set at one hop greater than the targeted firewall.

• 在实际应用中，趟火墙与路由跟踪技术类似，工作时把一跳的生存时间字段设定大于目标防火墙的TCP或UDP包送进防火墙。