VOS3000 SIP authentication 401 Unauthorized vs 407 Proxy Authentication Required. Configure digest authentication challenge mode SS_AUTHCHALLENGEMODE in system parameters.
VOS3000 iptables SIP Scanner: Block OPTIONS Floods Without Fail2Ban
VOS3000 iptables SIP scanner blocking guide. Block SIP OPTIONS floods, limit UDP connections, and secure your VoIP server without Fail2Ban using pure iptables rules and VOS3000 native features.