IBM Z10 BUISNESS CLASS Z10 BC Reference Manual page 21

The FICON Express4, FICON Express2 and FICON
Express channels support native FICON and FICON
Channel-to-Channel (CTC) traffi c for attachment to servers,
disks, tapes, and printers that comply with the FICON
architecture. Native FICON is supported by all of the
z10 BC operating systems. Native FICON and FICON
CTC are defi ned as CHPID type FC.
Because the FICON CTC function is included as part of
the native FICON (FC) mode of operation, FICON CTC is
not limited to intersystem connectivity (as is the case with
ESCON), but will support multiple device defi nitions.
FICON Support for Cascaded Directors
Native FICON (FC) channels support cascaded directors.
This support is for a single hop confi guration only. Two-
director cascading requires a single vendor high integrity
fabric. Directors must be from the same vendor since
cascaded architecture implementations can be unique.
This type of cascaded support is important for disaster
recovery and business continuity solutions because it can
help provide high availability, extended distance connec-
tivity, and (particularly with the implementation of 2 Gb/sec
Inter Switch Links) has the potential for fi ber infrastructure
cost savings by reducing the number of channels for inter-
connecting the two sites.
IBM
Two site non-cascaded director
topology. Each CEC connects to
directors in both sites.
With Inter Switch Links (ISLs),
less fiber cabling may be needed
for cross-site connectivity
FCP Channels
z10 BC supports FCP channels, switches and FCP/ SCSI
disks with full fabric connectivity under Linux on System
z and z/VM 5.2 (or later) for Linux as a guest under z/VM,
under z/VM 5.2 (or later), and under z/VSE 3.1 for system
usage including install and IPL. Support for FCP devices
means that z10 BC servers are capable of attaching to
select FCP-attached SCSI devices and may access these
devices from Linux on z10 BC and z/VSE. This expanded
attachability means that enterprises have more choices
for new storage solutions, or may have the ability to use
existing storage devices, thus leveraging existing invest-
ments and lowering total cost of ownership for their Linux
implementations.
The same FICON features used for native FICON chan-
nels can be defi ned to be used for Fibre Channel Protocol
(FCP) channels. FCP channels are defi ned as CHPID type
FCP. The 4 Gb/sec capability on the FICON Express4
channel means that 4 Gb/sec link data rates are available
for FCP channels as well.
21
IBM
Two Site cascaded director
topology. Each CEC connects to
local directors only.