McDATA Eclipse 2640 SAN, Administration And Configuration Manual

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Eclipse™ 2640 SAN Router Administration and Configuration Manual
Introduction
Introduction
An iSAN (internetworked storage area network) is a collection of one
or more fabrics interconnected using one or more SAN Routers,
where at least one fabric is in a distant location outside the metro
area. An iSAN is characterized by high latency and low bandwidth
inter-switch links (T1, T3, OC3, etc.) such as those found in wide area
networks. An iSAN has at least two SAN Routers that are
interconnected using iFCP connections. An iSAN is also a collection
of two or more mSANs. SAN routing done within an iSAN is referred
to as iSAN Routing or SAN Routing over distance.
Figure 4-1,
iSAN Configuration Example
illustrates two mSANs
interconnected through an iFCP link to create an iSAN. iFCP
interswitch links (ISLs) can be used to overcome scalability limits of a
single mSAN. iFCP is also recommended for connection across a
WAN, as this provides higher performance when using features such
as FastWrite and compression.