USOO7702762B1 (12) United States Patent (10) Patent No.: US 7,702,762 B1 Jagana (45) Date of Patent: Apr. 20, 2010 (54) SYSTEM FOR HOST TO-HOST 6,493.825 B1* 12/2002 Blumenau et al. ........... T13,168 CONNECTIVITY USING FICON PROTOCOL 6,499,058 B1* 12/2002 Hozumi ............... ... TO9,225 OVER A STORAGE AREANETWORK 6,636,529 B1 * 10/2003 Goodman et al. ... 370/469 6,654,830 B1 * 1 1/2003 Taylor et al. .................. 71 Of 74 (75)75 Inventor: Venkata R. Jagana, Portland, OR (US) 6,665,7146,658,540 B1* 12/2003 SicolaBlumenau et al. et al....... ........... ... 709/222711,162 (73) Assignee: states insists 6,714,9526,684,209 B2*B1 3/20041/2004 Ito(Shane et al. ........................ at O'707:01 707/9 s s 6,718,347 B1 * 4/2004 Wilson .......... ... TO7,201 c - 6,728,803 B1 * 4/2004 Nelson et al. ................. T10/60 (*) Notice: Subject to any disclaimer, the term of this 6,769,021 B1* 7/2004 Bradley ......... ... TO9.220 patent is extended or adjusted under 35 2003/0236945 A1 12/2003 Nahum ....................... 711 114 U.S.C. 154(b) by 2415 days. OTHER PUBLICATIONS (21) Appl. No.: 09/686,049 Computer Desktop Encyclopedia entry for "SAN” (copyright 1981 (22) Filed1C Oct.cl. 11,1 2000 2004), version 174, 4th Quarter 2004. * cited by examiner (51) Int. Cl. G06F 5/73 (2006.01) E. Early line Pich (52) U.S. Cl. ....................... 709:23.700,246.700,249 (74) Attorney, Agent, or Firm Jason O. Piche 37Of 466 57 ABSTRACT (58) Field of Classification Search ................. 709/249, (57) 709/246 s 223,s 224,s 217 s 219; 370/465. 467 Th e invention comprisesp a SVy Stem for providinghproviding host-to-host h See application file for complete search history. connectivity through use of SAN. In the preferred embodi (56) References Cited ment, the end-to-end host connectivity is accomplished through the FICON protocol, over the Fiber Channel layered U.S. PATENT DOCUMENTS stack on a standard Fiber Channel adapter that runs transpar 5,867,648 A * 2, 1999 Foth et al. ................... TO9/230 ently across the SAN infrastructure. 6, 199,112 B1* 3/2001 Wilson ....................... 709,227 6,400,730 B1* 6/2002 Latif et al. .................. 370/466 26 Claims, 8 Drawing Sheets 4. 15 8 / TCP/IP and SNA over FICON SCSI & FICONover FC FICON over FC 19 Storage / 6 16 17 U.S. Patent Apr. 20, 2010 Sheet 1 of 8 US 7,702.762 B1 Host B (Mainframe) SCSI Over FC FCOX1over FC Storage 2 Prior Art FIG. U.S. Patent Apr. 20, 2010 Sheet 2 of 8 US 7,702,762 B1 Cy network s 2. Prior Art FIG. 2 FCON over FC 19 Storage / 17 s FG, 3 U.S. Patent Apr. 20, 2010 Sheet 3 of 8 US 7,702,762 B1 838. 3. U.S. Patent Apr. 20, 2010 Sheet 4 of 8 US 7,702,762 B1 Applications 31 32 33 Emulation avers 34 ESCON Protocol Physical Fiber 35 Prior Art FIG.S SCSI protocol 37 Fiber Channel 38 strack Physical Fiber -39 Prior Art. F.G. 6 40 44 Applications .41 FICON protocol Fiber Channel - 42 TCP/IP 46 strack PhysicalP FiberP 43 Ethernet/Token Ring 47 Prior Art FIG. 7 U.S. Patent Apr. 20, 2010 Sheet 5 of 8 US 7,702,762 B1 67 09 I? 8"?INH Iooo?oudNOOISI U.S. Patent Apr. 20, 2010 Sheet 6 of 8 US 7,702.762 B1 hannel to Switch FIG. 9 U.S. Patent Apr. 20, 2010 Sheet 7 of 8 US 7,702,762 B1 evca Asukate : tw S232 f FC VA F. SWrvices wasgo. wer -- Seo-g C (25 G. 10 U.S. Patent Apr. 20, 2010 Sheet 8 of 8 US 7,702,762 B1 OO -> / FG. L. US 7,702,762 B1 1. 2 SYSTEM FOR HOST TO-HOST Area-Network) utilize configurations connected to PCs, serv CONNECTIVITY USING FICON PROTOCOL ers, print and storage devices, so too does FC. However, OVER A STORAGE AREANETWORK because FC uses fiber optic cabling, connections along a FC network are possible. Another feature of FC is its ability to BACKGROUND OF THE INVENTION provide increased bandwidth over communications channels. ESCON (Enterprise Systems Connection) is a fiber-based 1. Technical Field protocol. The ESCON protocol allows various emulations to This invention relates to network connectivity between run on top of it for further communication with the mainframe host computer systems over storage area networks (SANs) either directly or indirectly through ESCON emulators. How using the SAN's network protocol such as the FICON proto 10 ever, in order to perform this connectivity, the non-mainframe col. hosts need a separate ESCON hardware adapter, as well as 2. Description of the Prior Art other limitations. Network architecture is a blueprint that is used to guide the ESCON based physical channel speeds are 17 Mbps. design and implementation of networks. These blueprints are ESCON network connectivity is usually accomplished used because networks are not fixed at a single point in time, 15 through ESCON directors and hence the distances between but evolve to accommodate changes in both the underlying the end-hosts are limited. ESCON requires a repeater every technologies upon which they are based as well as changes in 1.86 miles. This requirement leads to increased costs when the demands placed on them. The primary function of a net the machines or hosts that are to be connected are far apart. work is to provide general cost-effective, robust and high By comparison, FICON (Fibre Connectivity) Channel is a performance connectivity among a large number of comput protocol that is targeted to provide high-speed storage Input/ CS. Output (I/O) capability. FICON provides a theoretical Channels and networks are the two primary ways that data throughput of 100 Mbytes/sec, which allows it to be used in a is transferred between devices such as processors, and periph SAN (Storage Area Network) environment. erals such as printers. Channels transfer data through Addressing the need for a centralized storage management Switched or direct point-to-point connections and they work 25 solution across heterogeneous networked resources, FC SAN by creating a fixed connection between the Source and desti architecture benefits a typical networked environment by nation devices until the transfer is complete. Channels trans delivering a dedicated storage environment, and by using of fer data at high speeds and are very economical. Networks, on high-speed fiber-optic or copper cabling to interconnect serv the other hand are collections of nodes Such as processors, ers, workstations and storage devices. print devices and workstations. Connections on networks are 30 As a data-channel network standard, the FC backbone of a slower than those made via channels. Channels work best SAN environment contains the network features that provide among few devices, and connect via predefined addresses. connectivity, distance and protocol multiplexing. Networks, on the other hand, can handle multiple requests Because FC SANs are protocol-independent, the support among multiple connections. Fibre Channel (FC) is a hybrid for network protocols like Tansmission Control Potocol/Iter of both network and channel methods and combines the best 35 net Potocol (TCP/IP) and audio/video is accomplished with a aspects of both. single physical layer. FC allows concurrent communication Host to host connectivity within a high-speed network among workstations, mainframes, servers, data storage sys environment is typically accomplished by using several dif tems and other peripherals using SCSI and IP protocols. The ferent types of network media. Network media include Token interconnectivity of computers and storage devices forms the Ring and Ethernet and other topologies. Token Ring is a 40 basis of a SAN. physical network technology in which hosts are connected in Although FC SAN is a fiber-based solution for high-speed a ring. A token (bit pattern) circulates around the ring and a storage access, there remains an industry need for high-speed, given node must possess the token before it is allowed to host to host connectivity that is an improvement upon the transmit. Token Ring has a bandwidth of 4 and 16 Mbps existing ESCON based architecture. (megabits per second). Fiber Distributed Data Interface 45 (FDDI) is a high-speed token ring networking technology SUMMARY OF THE INVENTION designed to run over optical fiber. The cables used for the token ring network are attached to adapters instead of the The invention comprises a system and method for provid hosts themselves. Ethernet is a network technology that uses ing host-to-host connectivity through use of SAN. In the CSMA/CD (Common Sense Multiple Access) and has a 50 bandwidth of 10Mbps or 100Mbps. The Ethernet protocol is preferred embodiment, the end-to-end host connectivity is implemented in hardware on the network adapter. accomplished through the FICON protocol, over the Fibre ASAN is a dedicated, centrally managed, secure informa Channel layered stack on a standard Fibre Channel adapter tion infrastructure which enables any-to-any interconnection that runs transparently across the SAN infrastructure. of servers and storage systems. SANS allows for connection 55 Other features and advantages of this invention will between storage devices and host machines across greater become apparent from the following detailed description of distances than are possible on a traditional local area network the presently preferred embodiment of the invention, taken in (LAN). SANs enable users to store large Volumes of data at conjunction with the accompanying drawings. remote locations called libraries. SANs are rapidly being BRIEF DESCRIPTION OF THE DRAWINGS integrated into distributed environments using Fibre Channel 60 technology.