Brocade Access Gateway Administrator's Guide - Supporting Fabric OS v5.3.0 (53-1000633-01, June 2007)

Access Gateway Administrator’s Guide 3

53-1000633-01

Access Gateway port types

Brocade Access Gateway differs from a typical fabric switch because it connects to the fabric using

node ports (N_Ports). Typically fabric switches connect to the enterprise fabric using ISL

(InterSwitch Link) ports, such as an E_Port.

The following defines the Fibre Channel (FC) port terms used in this manual:

- F_Port, fabric port. A switch port that connects a host, HBA, or storage device to the SAN.

- N_Port, node port. A host, HBA, or storage device port that connects to the F_Port of the

fabric switch.

COMPARING FC PORT CONFIGURATIONS

Brocade Access Gateway multiplexes host connections to the fabric. It presents an F_Port to the

host and an N_Port to an edge fabric switch. Using N_Port ID virtualization (NPIV), Brocade Access

Gateway allows multiple FC initiators to access the SAN on the same physical port. This reduces the

hardware requirements and management overhead of hosts to the SAN connections.

A fabric switch presents F_Ports (or FL_Ports) to the host and storage devices and presents

E_Ports, TE_Ports, or EX_Ports to other switches in the fabric. A fabric switch consumes SAN

resources, such as domain IDs, and participates in fabric management and zoning distribution. A

fabric switch requires more physical ports than Brocade Access Gateway to connect the same

number of hosts.

Figure 2 compares the types of ports used by the Access Gateway to those used by a typical fabric

switch.

FIGURE 2 Port usage comparison

N_Port

F_Port

N_Port

F_Port

N_Port

F_Port

Hosts

Access Gateway

Edge Switch

Fabric

enabled

NPIV

N_Port

F_Port

E_Port

N_Port

F_Port

Hosts

Edge Switch

Fabric Switch

E_Port

Fabric

Access Gateway Ports

Fabric Switch Ports