Storage Networking Architectures
Storage Transport Protocols
Channels and Networks
I/O Channel (e.g. SCSI) Network (e.g. Ethernet)
x Few devices 9Many devices
x Static addressing 9Dynamic addressing
x High latency 9Low latency
x Short distances 9Long distances
x Software-based 9Hardware-based
delivery management delivery management
I/O bus (channel) architecture:
A channel is a directly attached and well-structured mechanism
designed to transmit data between a host and a small number of devices
in a well-known configuration.
Because channels are static and well-structured, data can be routed
between devices with minimal delays, providing low latency.
Channels generally use a parallel architecture. This architecture can
support high speeds, but only short distances.
Due to the static and well-structured nature of channels, they perform
only minimal decision-making tasks. These tasks can be performed by
hardware, which ensures a minimal load on the host’s CPU and provides
rapid delivery.