Справочник Пользователя для IBM Flex System V7000 Expansion Enclosure 4939H29

Chapter 11. SAN Connections and Configuration 

Draft Document for Review January 29, 2013 12:52 pm

In a Fibre Channel environment the unique identity of participants are maintained through a 
hierarchy of fixed names and assigned addresses identifiers. In Fibre Channel terminology, a 
communicating device is a node. Each node has a fixed 64-bit Node_name assigned by the 
manufacturer. The node name will be unique if the manufacturer has registered a range of 
addresses with the IEEE, and so is normally referred to as a World-Wide Name. An N_Port 
within a parent (WWN) node is also assigned a unique 64-bit Port_Name, which aids the 
accessibility of the port and is known as the Port World-Wide Name (PWWN).

In FC SAN environments, the FC switch is responsible for assigning a 24-bit address to each 
device as it logs on. Allowing the topology to manage the assignment of addresses has the 
advantage that control of the addresses is now performed by the entity that is responsible for 
the routing of information. This means that address assignments can be made in a manner 
that results in the most efficient routing of frames within that topology. 

There are six standard kinds of ports, those used with IBM Flex System V7000 Storage Node 
are listed below:

– Node ports (N_Port), these ports are found in Fibre Channel nodes, which are defined 

to be the source or destination of information units (IU). I/O devices and host systems 
interconnected in point-to-point or switched topologies use N_Ports for their 
connection. N_Ports can only attach to other N_Ports or to F_Ports.