My network is configured with a consumer grade router which is used to separate four public addresses provided by my ISP. All of the addreses are static addresses. The gateway address is asigned to the router and then the othe ip addresses are statically asigned to each host. One address host is a SonicWall TZ 210W firewall/router to the main corp network. Recently I started receiving firewall Alerts from the SonicWall indicating that the NTP server responce was invalid or incomplete, so I ran some diagnostics from each of the host and they all failed to communicate with the external NTP being used. This leads me to believe that the router between the internet connection and each of the host is blocking or interfering with the traffic or UDP 123. How can I verify this?