1. Configuration of user groups will be extended with additional TAB showing list host group with associated pairs of tags & values.
a. Tag as well as tag value are optional. A host group without associated tags may exist.
b. Different tags with different values must be supported.

2. Zabbix will take into account problem tag filtering for:
a. Monitoring?Problems, Monitoring?Dashboard (all widgets displaying problem-related information)
b. Alerting: sending of alerts to users with no tag permissions will be suppressed
c. API methods: event.get and problem.get will be extended to take into account problem tag filtering

3. How filtering works:
a. If not filters exist for a given user group, then no filtering is applied.
b. If only host group is given with no tags, then it is allowed to display problem of this specific host group
c. If only tag name is given without tag value, then all problems having this tag name should be displayed
d. If both tag name and tag value are given, then it's allowed to display problem having Tag==<tag name> Tag value==<tag value>
e. If an user is a member of several host groups, then permissions granted for each host group are combined using OR condition.
f. If there are several tag names having same value, then filtering will use OR condition for tag values. For example: Host group ABC: Service: MySQL Service: Oracle. In this case it will be transformed into Problem belong to Host group ABC nad has tag "Service" with value either "MySQL" or "Oracle"