190a392d_th_PHP___Page_2___WebReference__Flags
[Filter] FILTER_VALIDATE_IP [Options] No Options [Description] Checks that a value is an IP address. Flags allow you to specify only IPv4 or IPv6, or not from private or reserved ranges. [Flags] 
FILTER_FLAG_IPV4 FILTER_FLAG_IPV6 FILTER_FLAG_NO_PRIV_RANGE FILTER_FLAG_NO_RES_RANGE
Data Filtering with PHP / Page 2 | WebReference
Flags