You can use a WWPN to associate a LUN for fibre-channel attachment.
For fibre-channel attachment, LUNs have an affinity to the host's fibre-channel adapter through the worldwide port name (WWPN) for the host adapter. In a switched fabric configuration, a single fibre-channel host adapter could have physical access to multiple fibre-channel ports on the storage unit. In this case, you can configure the storage unit to allow the host to use either some or all of the physically accessible fibre-channel ports on the storage unit.
For fibre-channel attachment, each fibre-channel host adapter can architecturally attach up to 2 LUNs. The storage unit supports 64K LUNs and a maximum LUN size of 2TB divided into a maximum of 16 logical subsystems each with up to 256 LUNs. You can configure no more than 256 of the LUNs in the storage unit to be accessible by that host.