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23-397: FICON was introduced in 1998 as part of System/390 G5 IBM mainframe . In July 2013, FICON replaced ESCON in new zEnterprise BC12/EC12 , and later models, because of FICON's technical superiority (especially its higher performance) and lower cost. Each FICON channel port is capable of multiple concurrent data exchanges (a maximum of 32) in full duplex mode. Information for active exchanges

46-469: A Parallel Sysplex has at least two CFs and/or ICFs for redundancy, especially in a production data sharing environment. Server Time Protocol (STP) replaced the Sysplex Timers beginning in 2005 for System z mainframe models z990 and newer. A Sysplex Timer is a physically separate piece of hardware from the mainframe, whereas STP is an integral facility within the mainframe's microcode. With STP and ICFs it

69-408: A Parallel Sysplex include: The Coupling Facility may be either a dedicated external system (a small mainframe, such as a System z9 BC, specially configured with only coupling facility processors) or integral processors on the mainframes themselves configured as ICFs (Internal Coupling Facilities). It is recommended that at least one external CF be used in a parallel sysplex. It is recommended that

92-564: A channel port may send Command or Command and Data IUs, while only a control unit port may send Status IUs. As with prior IBM mainframe channel protocols, there is a concept of a channel to control unit "connection". In its most primitive form, a connection is associated with a single channel program. In practice, a single channel program may result in the establishment of several sequential connections. This normally occurs during periods where data transfers become dormant while waiting for some type of independent device activity to complete (such as

115-471: A channel – control unit connection – one for each direction. So while a Fibre Channel exchange is capable of carrying a command and response on a single exchange, and all other FC-4 protocols work that way, the response to a FICON IU is always on a different exchange from the IU to which it is a response. The two exchanges that implement a connection are called an exchange pair (Note that

138-555: A single time source between multiple servers. Based on Network Time Protocol concepts, one of the System z servers is designated by the HMC as the primary time source (Stratum 1). It then sends timing signals to the Stratum 2 servers through use of coupling links. The Stratum 2 servers in turn send timing signals to the Stratum 3 servers. To provide availability, one of the servers can be designated as

161-401: A transaction-processing system the recovery process reconstructs the transaction data from log files. If time stamps are used for transaction-data logging, and the time stamps of two related transactions are transposed from the actual sequence, then the reconstruction of the transaction database may not match the state before the recovery process. Server Time Protocol (STP) can be used to provide

184-481: A workload for high performance and high availability . In 1990, IBM mainframe computers introduced the concept of a Systems Complex , commonly called a Sysplex , with MVS /ESA SPV4.1. This allows authorized components in up to eight logical partitions (LPARs) to communicate and cooperate with each other using the XCF protocol. Components of a Sysplex include: Users of a (base) Sysplex include: IBM introduced

207-428: Is a common name for IBM products . Models and lines: Technologies: IBM Parallel Sysplex#Geographically Dispersed Parallel Sysplex In computing, a Parallel Sysplex is a cluster of IBM mainframes acting together as a single system image with z/OS . Used for disaster recovery, Parallel Sysplex combines data sharing and parallel computing to allow a cluster of up to 32 systems to share

230-501: Is divided into fixed block storage volumes (accessed with FCP) and mainframe-specific CKD/ECKD storage volumes (accessed with FICON and/or ESCON). Disk storage products that can be attached via FICON include: Tape storage facilities include: Hardware Security Module (HSM) products that support FICON include: Switches/directors that support FICON include: Managed File Transfer products that support FICON include: Other older FICON switching platforms are still in use. These include

253-459: Is in addition to the standard Fibre Channel CRC used to verify the integrity of each individual FC frame. As such, the FICON CRC has the capability of detecting missing or out of sequence frames/IUs. FICON may employ Fibre Channel fiber optic cables with either short wavelength (multi-mode; 62.5 or 50 micrometer core) or long wavelength (single mode; 9 micrometer core). Long wavelength is used in

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276-423: Is possible to construct a complete Parallel Sysplex installation with two connected mainframes. Moreover, a single mainframe can contain the internal equivalent of a complete physical Parallel Sysplex, useful for application testing and development purposes. The IBM Systems Journal dedicated a full issue to all the technology components. Maintaining accurate time is important in computer systems. For example, in

299-542: Is technically quite similar to more popular storage protocols, such as FCP. Both FICON and FCP share levels 1–3 of Fibre Channel specifications. Some administrators argue that FICON offers somewhat easier troubleshooting in mainframe environments, but the inherent technical advantages and disadvantages between FICON and FCP are much alike. Some mainframe-specific setups, such as GDPS , require FICON (or its predecessor ESCON). Mainframe-attached storage, such as IBM's System Storage DS8000 , often supports both protocols. The storage

322-511: Is transferred in Fibre Channel sequences mapped as FICON Information Units (IUs) which consist of one to four Fibre Channel frames, only the first of which carries 32 bytes of FICON (FC-SB-3) mapping protocol. Each FICON exchange may transfer one or many such IUs. FICON channels use five classes of IUs to conduct information transfers between a channel and a control unit. They are: Data, Command, Status, Control, and lastly Link Control. Only

345-540: The 9032-3 and 9032-5 ESCON directors for IBM, as well as the FICON Bridge Card. Brocade has many co-patents with IBM for FICON and ESCON technology. Cisco Systems was a relative newcomer to this space, with their first FICON director coming out in 2003. Other manufacturers producing FICON-compatible equipment include Optica Technologies , and InfoPrint Solutions Company , which offers high-volume printers that can attach via FICON. IBM System IBM System -

368-493: The Fibre Channel physical (FC-2 and below) level, the communication is connectionless, frames and sequences may arrive out of order, and there is no acknowledgement of arrival. But all of that exists at the FC-4 level. The integrity of customer data carried within one or more IUs is protected by a running 32-bit cyclic redundancy check (CRC) contained in the last frame of an IU classified as an ending IU within each data transfer. This

391-451: The McDATA 6064, CNT UMD, and CNT (Inrange) FC/9000. Inrange was acquired by CNT in 2003, CNT was acquired by McDATA in 2005, and in 2007 McDATA was in turn acquired by Brocade Communications Systems . Approximately 80% of FICON directors and switches installed in mainframe environments were Brocade products at the time. McDATA was well established in the mainframe directors space, manufacturing

414-520: The Parallel Sysplex with the addition of the 9674 Coupling Facility (CF), new S/390 models, upgrades to existing models, coupling links for high speed communication and MVS/ESA SP V5.1 operating system support, in April 1994. The Coupling Facility (CF) may reside on a dedicated stand-alone server configured with processors that can run Coupling Facility control code (CFCC), as integral processors on

437-515: The System z server that can take advantage of this include: Other components can use the Coupling Facility to help with system management, performance, or reduced hardware requirements. Called “Resource Sharing”, uses include: Tape Switching uses the GRS structure to provide sharing of tape units between z/OS images. Multi-system enclave management for improved performance Major components of

460-447: The concept of the two exchanges being related exists only at the FC-4 layer). While other FC-4s have a single "data structure type" code that characterizes their IUs in Fibre Channel frame headers, FICON has two. One is for IUs from channel to control unit; the other for control unit to channel. Except for some initialization dialogue that requires stronger synchronization, FICON uses Fibre Channel class of service 3 (Datagram). Thus, at

483-460: The mainframes themselves configured as ICFs (Internal Coupling Facilities), or less common, as normal LPARs. The CF contains Lock, List, and Cache structures to help with serialization, message passing, and buffer consistency between multiple LPARs. The primary goal of a Parallel Sysplex is to provide data sharing capabilities, allowing multiple databases for direct reads and writes to shared data. This can provide benefits of Databases running on

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506-603: The majority of applications owing to its superior optical power budget and bandwidth. FICON cannot use Copper Fibre Channel cables. FICON is used exclusively with computers based on the IBM z/Architecture (current descendant of System/360 , System/370 , etc.), commonly called mainframes . FICON and its predecessors are the only protocols sufficient to communicate with traditional mainframe peripheral devices, especially for z/OS . However, most mainframe operating systems also support FCP ( SCSI command set over Fibre Channel). FICON

529-594: The physical positioning of tape or a disk access arm). In such cases, the connection may be closed by action of the device's control unit with the signaling of appropriate status. When the control unit is ready to resume such an interrupted connection, it signals the channel to reconnect and resume the interrupted channel program. By closing temporarily dormant connections, channel and control unit facilities may be better utilized to serve other active channel programs and certain protocol timeouts that might otherwise occur may be avoided. FICON uses two Fibre Channel exchanges for

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