HP Surestore 6164 Switch - Manual (Page 16)

16 Zoning User’s Guide
Zone Types
Zones can be hard (hardware enforced) or soft (advisory). In a hard zone,
sometimes referred to as a port zone, zone members are specified by
physical port number. In a soft zone, at least one zone member is specified
logically by worldwide name (WWN).
Hard Zones
In a hard zone, all zone members are specified as switch ports; any number
of ports in the fabric can be configured to the zone. When a zone member is
specified by port number, only the individual device port specified is
included in the zone.
Hard zones are position-dependent, that is, a device is identified by the
physical port to which it is connected. Switch hardware ensures that there is
no data transfer between unauthorized zone members. However, devices
can transfer data between ports within the same zone. Consequently, hard
zoning provides the greatest security possible; you can use it where security
must be rigidly enforced.
Soft Zones
In a soft zone, at least one zone member is specified by WWN. A device is
included in a zone if either the node WWN or port WWN specified matches
an entry in the name server table.
When a device logs in, it queries the name server for devices within the
fabric. If zoning is in effect, only the devices in the same zone (or zones)
are returned. Other devices are hidden from the name server query reply.
When a WWN is specified, all ports on the specified device are included in
the zone.
Soft zones are name server-dependent and therefore provide more
flexibility - new devices can be attached without regard to physical
location. However, the switch does not control data transfer, so there is no
guarantee against data transfer from unauthorized zone members. You can
use soft zoning where flexibility is important and security can be ensured
by the cooperating hosts.
In addition to hard and soft zones, a third type of zone is available.