FIELD OF INVENTION
[0001] The present subject matter relates to communication between fibre channel (FC) switches and, particularly, but not exclusively, to establishing a 5 connection between FC switches.
BACKGROUND
[0002] Storage area networks (SANs) are deployed in enterprises, educational institutions, data centers, and government institutions for efficient storage and communication of data. Such SANs, typically, implement Fibre Channel (FC) 10 technology for facilitating high speed data transmission between network elements, such as storage devices, databases, tape disks, hubs, and servers present in the SANs. In order to interconnect the network elements present in a SAN, FC switches, i.e., switches compatible with the FC technology are deployed in the SAN. The FC switches facilitate in establishing a connection between the network elements for 15 communication of data and management of network traffic amongst the network elements.
SUMMARY
[0003] This summary is provided to introduce concepts related to communication between Fibre Channel (FC) switches. This summary is not intended 20 to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the claimed subject matter.
[0004] In one implementation, a method for establishing a connection between FC switches is disclosed. The method comprises, converting, by a first gateway, an FC Exchange Link Parameters (ELP) frame received from a first FC 25 switch to a Fibre Channel over Ethernet (FCoE) Initialization Protocol (FIP) ELP
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frame, where the FC ELP frame is indicative of a request to establish a connection with a second FC switch. The method further comprises, transmitting, by the first gateway, the FIP ELP frame to a second gateway over a communication network, where the second gateway is connected to the second FC switch. The method further comprises receiving, by the first gateway, a connection establishment response 5 message from the second gateway for establishing the connection between the first FC switch and the second FC switch.
[0005] In another implementation, a gateway is disclosed. The gateway includes a processor and a frame conversion module coupled to the processor. In one implementation, the frame conversion module converts an FC Exchange Link 10 Parameters (ELP) frame received from a first FC switch to a Fibre Channel over Ethernet (FCoE) Initialization Protocol (FIP) ELP frame, where the FC ELP frame is indicative of a request to establish a connection with a second FC switch. The gateway also includes a communication module coupled to the processor to transmit the FIP ELP frame to a second gateway over a communication network, where the 15 second gateway is connected to the second FC switch. The communication module further receives a connection establishment response message from the second gateway for establishing the connection between the first FC switch and the second FC switch.
[0006] In another implementation, a gateway is disclosed. The gateway 20 includes a processor and a frame conversion module coupled to the processor. The frame conversion module converts a Fibre Channel over Ethernet (FCoE) Initialization Protocol (FIP) ELP frame received from another gateway to an FC Exchange Link Parameters (ELP) frame, where the other gateway is connected to a first FC switch, and where the FC ELP frame is indicative of a request to establish a 25 connection with a second FC switch connected to the gateway. The gateway also includes a communication module coupled to the processor to transmit a connection establishment response message received from the second FC switch to the other
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gateway for transmission to the first FC switch, where the connection response message indicates one of an acceptance and a rejection to establish the connection with the first FC switch.
[0007] In accordance with another implementation of the present subject matter, a non-transitory computer-readable medium having embodied thereon a 5 computer program for executing a method is disclosed. The method comprises, converting, by a first gateway, an FC Exchange Link Parameters (ELP) frame received from a first FC switch to a Fibre Channel over Ethernet (FCoE) Initialization Protocol (FIP) ELP frame, where the FC ELP frame is indicative of a request to establish a connection with a second FC switch. The method further comprises, 10 transmitting, by the first gateway, the FIP ELP frame to a second gateway over a communication network, where the second gateway is connected to the second FC switch. The method further comprises receiving, by the first gateway, a connection establishment response message from the second gateway for establishing the connection between the first FC switch and the second FC switch. 15
BRIEF DESCRIPTION OF THE FIGURES
[0008] The detailed description is provided with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some 20 embodiments of system and/or methods in accordance with embodiments of the present subject matter are now described, by way of example only, and with reference to the accompanying figures, in which:
[0009] Figure 1 illustrates an exemplary network environment implementation for establishing a connection between FC switches, according to an 25 embodiment of the present subject matter; and
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[0010] Figure 2 illustrates components of a first gateway and a second gateway for establishing a connection between FC switches, according to an embodiment of the present subject matter; and
[0011] Figure 3 illustrates a method for establishing a connection between FC switches, according to an embodiment of the present subject matter. 5
DESCRIPTION OF EMBODIMENTS
[0012] A storage area network (SAN) comprises several network elements, such as servers, databases, and storage devices interconnected with each other through a plurality of Fibre Channel (FC) switches deployed in the SAN. An FC switch may be understood as a switch compatible with FC technology implemented 10 in the SAN for facilitating high speed data transmission amongst the network elements. As may be understood, for facilitating communication between the network elements, the FC switches present in the SAN are also interconnected. For example, a first FC switch connected to a first set of network elements may be connected to a second FC switch connected to another set of network elements. Thus, the 15 interconnected FC switches render support for communication amongst the network elements present in the aforementioned sets of network elements. Typically, the FC switches are interconnected via optical fibre cables and there exists a point-to-point connection between each pair of FC switches. Owing to the complexity associated with deployment, management, and maintenance of the optical fibre cables, 20 interconnecting the FC switches proves to be a cumbersome task. Moreover, in cases where two FC switches are distantly located in the SAN, extensive cable needs to be deployed for interconnecting the FC switches. As a result, overall cost associated with deployment of the SAN may increase.
[0013] In a known technique used for interconnecting distantly located FC 25 switches, a Fibre Channel Forwarder (FCF) is deployed at respective sites of deployment of the FC switches. For instance, for interconnecting a first FC switch
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deployed at, say, a first floor of a datacenter with a second FC switch located at, say, a third floor of the datacenter, a FCF may be deployed at each of the aforesaid floors. The FCF connected to the first FC switch is referred to as a first FCF and the FCF connected to the second FC switch is referred to as a second FCF, hereinafter. The FCF may be understood as a network device which facilitates transmission of 5 network traffic amongst the FC switches over an Ethernet based communication network. In order to support the transmission of the network traffic, the Ethernet based communication network implements Fibre Channel over Ethernet (FCoE) technology. The Ethernet based communication network implementing the FCoE technology is hereinafter referred to as FCoE network. Typically, when an FCF is 10 deployed in or connects to the FCoE network, the FCF may perform a FCoE Initiation Protocol (FIP) discovery mechanism for discovering other FCF's present in or connected to the FCoE network. The FCF may subsequently establish a connection with the other FCF's. Thus, the first FCF and the second FCF may also establish a connection between themselves. . 15
[0014] With reference to the above technique, the first FCF establishes a connection with the first FC switch and the second FCF establishes a connection with the second FC switch. Typically, the aforesaid connection is established based on an Exchange Link Parameters (ELP) protocol. As a part of the ELP protocol, the first FC switch transmits an FC ELP frame to the first FCF. Upon receiving the FC ELP, the 20 first FCF establishes the connection with the first FC switch. The connection between the second FCF and the second FC switch is established in a similar manner.
[0015] Thus, upon establishment of the connection between the first FC switch and the first FCF, the connection between the first FCF and the second FCF, and the connection between the second FCF and the second FC switch, the first FC 25 switch and the second FC switch are deemed to be connected. As may be gathered, time associated with establishment of the aforementioned connections may result in increasing the overall time associated with the interconnection of the first FC switch
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and the second FC switch. In addition, the FCFs are costly devices and thus, deployment and maintenance of the FCFs may increase the overall implementation cost of the SAN.
[0016] Further, the architecture of the SAN is such that it supports a limited number of domain identities (ID's). A domain ID may be understood as an identity 5 assigned to each network element deployed in the SAN. Thus, deployment of a network element results in consumption of a domain ID. As will be clear from the foregoing description, the deployment of the FCFs may thus consume the domain ID's. As a result, the scalability of the SAN architecture may be reduced.
[0017] The present subject matter describes systems and methods for 10 establishing a connection between FC switches. In accordance with the present subject matter, a gateway for facilitating establishment of the connection between the FC switches is disclosed.
[0018] In an example, in order to establish a connection between a first FC switch and a second FC switch located at a different sites, a gateway may be 15 deployed at each of the first FC switch's and the second FC switch's location. For example, a first gateway may be deployed at the first FC switch's location and a second gateway may be deployed at the second FC switch's location. The first gateway may further communicate with the second gateway over a communication network, such as the FCoE network. 20
[0019] As mentioned previously, the connection between two FC switches is established based on the ELP protocol. In an implementation, for facilitating establishment of the connection, the first gateway may transmit the FC ELP frame received from the first FC switch to the second gateway for transmittal to the second FC switch. In said implementation, the first gateway may convert the FC ELP frame 25 to a FIP ELP frame for transmission to the second gateway over the FCoE network. For instance, the first gateway may encapsulate the FC ELP frame in a FIP header for
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obtaining the FIP ELP frame. The FIP ELP header may include a destination MAC address of the second gateway. The FIP ELP frame is then transmitted to the second gateway. Upon receiving the FIP ELP, the second gateway may decapsulate the FIP ELP header to obtain the FC ELP frame. The FC ELP frame is then transmitted to the second FC switch. 5
[0020] Upon receiving the FC ELP frame, the second FC switch may transmit a connection establishment response message to the first FC switch. In an example, the connection establishment response message may indicate whether the second FC switch has accepted/rejected the request for establishment of the connection. For instance, in a case where the second FC switch agrees to establish the connection, the 10 connection establishment response message may be a SW_ACC message. The SW_ACC message may be understood as an acceptance to establish the connection. In said example, upon receiving the connection establishment response, the connection between the first FC switch and the second FC switch is established. Thereafter, data traffic, i.e., data packets arriving from the first FC switch is 15 transmitted to the second FC switch over the FCoE network. For example, upon receiving the data packets from the first FC switch, the first gateway may switch the data packets to the second gateway. The second gateway subsequently transmits the data packets to the second FC switch.
[0021] The present subject matter thus facilitates in establishing the 20 connection between the FC switches. In accordance with the present subject matter, the FC ELP frames are converted to FIP ELP frames which can be sent over the FCoE network for establishment of the connection. As a result, a single connection between the FC switches may be established, through the gateways, without deploying the FCFs for interconnecting the FC switches over the FCoE networks. 25 The connection established through the gateways, in accordance with the present subject matter, is less complex in comparison to the connection established through the FCFs. Also, without the FCFs in the network, the cost of implementing the
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network is substantially reduced. Further, no domain ID is required to be assigned to the gateway thereby maintaining the scalability of a SAN in which the gateway is deployed. Moreover, as the gateway facilitates establishment of the connection over the FCoE network, the need for implementing optical fibre cables for connecting the FC switches is averted. As a result, complexity and cost associated with deployment 5 and maintenance of the optical fibre cables for connecting the FC switches is reduced.
[0022] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the present subject matter and 10 are included within its spirit and scope. Further, all examples recited herein are principally intended expressly to be only for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all 15 statements herein reciting principles, aspects, and embodiments of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.
[0023] The manner in which the systems and the methods for communication between FC switches shall be implemented has been explained in details with respect 20 to the Figures 1, 2 and 3. While aspects of described systems and methods for communication between FC switches can be implemented in any number of different computing systems, transmission environments, and/or configurations, the embodiments are described in the context of the following exemplary system(s).
[0024] Figure 1 illustrates a network environment 100 for establishing a 25 connection between FC switches. The network environment 100 includes a plurality of FC switches 102-1, 102-2, 102-3, ...., 102-N, hereinafter collectively referred to as FC switches 102 and individually referred to as FC switch 102. The FC switches 102
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interconnect storage devices (not shown) and processing devices (not shown) present in a storage area network (SAN). In an example, the storage device and the processing devices may communicate with each other using the FC switches 102.
[0025] The network environment 100 further includes a plurality of gateways 104-1 to 104-N, interconnected with each other through a communication network 5 106. The gateways 104-1 to 104-N are hereinafter collectively referred to as gateways 104 and individually referred to as gateway 104. The communication network 106 can be a collection of individual networks, interconnected with each other and functioning as a single large network (e.g., the internet or an intranet). For example, the communication network 106 may be a Local Area Network (LAN) a lossless 10G 10 Ethernet network, and the like. Further, depending on the technology, the communication network 106 may include various network entities, such as switches, hubs, routers; however, such details have been omitted for ease of understanding. In an implementation, the communication network 106 may implement Fibre Channel over Ethernet (FCoE) technology for supporting transmission of network traffic 15 between the FC switches 102. The communication network 106 implementing the FCoE technology may be, hereinafter, interchangeably referred to as FCoE network 106.
[0026] In an implementation, each of the gateways 104 may include one or more Tunnel E_Ports (TE_Ports) and one or more Virtual Extension (VE) Ports. A 20 TE_Port may be understood as an FC Port configured for facilitating the gateway 104 to connect to the FC switch 102. A VE Port may be understood as an Ethernet Port configured for facilitating the gateway 104 to connect with the communication network 106. As shown in the figure, the gateway 104-1 includes the TE_Ports 108-1, 108-2, and 108-3, and the VE Ports 110-1, 110-2, and 110-3. Further, the gateway 25 104-N includes the TE_Ports 108-4, 108-5, and 108-N, and the VE Ports 110-4, 110-5, and 110-N. As may be understood, the gateway 104-1 and the gateway 104-N may include additional TE_Ports and VE Ports which are not shown in the figure for the
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sake of brevity. The TE_Ports 108-1, 108-2, ......., 108-N are hereinafter collectively referred to as TE_Ports 108 and individually referred to as TE_Port 108. The VE Ports 110-1, 110-2, ......, and 110-N are hereinafter collectively referred to as VE Ports 110 and individually referred to as VE Port 110.
[0027] In an implementation, the gateways 104 may be configured to 5 facilitate establishment of a connection between the FC switches 102. For example, the gateway 104-1 and the gateway 104-N may be configured for establishing facilitating establishment of a connection between the FC switch 102-1 and the FC switch 102-3. In said example, the gateway 104-1 and the gateway 104-N may be configured on a same virtual local area network (VLAN). The gateway 104-1 may 10 connect to the FC switch 102-1 through the TE_Port 108-3 and to the communication network 106 through the VE Port 110-3. Further, the gateway 104-N may connect to the FC switch 102-3 through the TE_Port 108-N and to the communication network 106 through the VE Port 110-N. Thus, the TE_Ports, 108-3 and 108-N, and the VE Ports, 110-3 and 110-N, are associated with the same VLAN as that of the gateways 15 104-1 and 104-N.
[0028] As may be understood, upon completion of the configuration, the gateway 104-1 and the gateway 104-N, respectively, may learn about each other's functionality via the FIP discovery mechanism.. Thus, upon completion of the FIP discovery mechanism, the gateway 104-1 and the gateway 104-2 are aware of each 20 other's capability to facilitate establishment of the connection between the FC switch 102-1 and the FC switch 102-3. Further, the gateway 104-1 may store a source Media Access Control (MAC) address of the gateway 104-N, and vice-versa, for future communication.
[0029] In an example, the TE_Port 108-3 of the gateway 104-1 may receive a 25 FC ELP frame from the FC switch 102-1 for establishing the connection with the FC switch 102-3. The gateway 104-1 may convert the FC ELP frame to an FIP ELP frame for transmission over the FCoE network 106. As may be understood, the FC
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ELP frame is in a format pertaining to FC technology. Thus, for enabling transmission over the FCoE network 106, the gateway 104-1 converts the FC ELP frame in a format, i.e., the FIP ELP frame, compatible for transmission over the FCoE network 106. Upon converting the FC ELP to the FIP ELP, the gateway 104-1 transmits the FIP ELP frame to the gateway 104-N over the FCoE network 106. For 5 example, the gateway 104-1 may transmit the FIP ELP through the VE Port 110-3. In an example, the VE Port 110-N of the gateway 104-N may receive the FIP ELP frame. Upon receiving the FIP ELP frame, the gateway 104-N may convert the FIP ELP frame in an FC compatible format. For the purpose, the gateway 104-N may decapsulate a header of the FIP ELP frame to obtain the FC ELP frame from the FIP 10 ELP frame. The gateway 104-N may then transmit the FC ELP frame to the FC switch 102-3.
[0030] Upon receiving the FC ELP frame, the FC switch 102-3 may transmit an acknowledgement message to the FC switch 102-1. For example, the FC switch 102-3 may transmit an ACK to the FC switch 102-1. As may be understood, the ACK 15 may be suitably converted to a compatible format by the gateways 104 when transmitting the ACK over the FCoE network 106. Upon sending the acknowledgement message, the FC switch 102-3 may choose to either accept or reject the FC ELP, thereby accepting or rejecting the request for establishing the connection with the FC switch 102-1. In an implementation, the FC switch 102-3 20 may transmit a connection establishment response message to the FC switch 102-1 to indicate the acceptance or rejection of the FC ELP. In said implementation, the FC switch 102-3 transmits the connection establishment response message to the gateway 104-N for transmission to the FC switch 102-1. The gateway 104-N may then transmit the connection establishment response message to the gateway 104-1 for 25 transmission to the FC switch 102-1. Upon receiving the connection establishment response message, the gateway 104-1 transmits the connection establishment response message to the FC switch 102-1.
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[0031] In a case where the FC switch 102-3 may concur to establish the connection, the connection establishment response message may be an SW_ACC message. In said case, upon receiving the connection establishment response message, the FC switch 102-1 transmits an acknowledgement message, similar to the acknowledgement message sent by the FC switch 102-3, to the FC switch 102-3 for 5 confirming establishment of the connection.
[0032] Thus, upon establishment of the connection, the gateway 104-1 may switch data traffic arriving from the FC switch 102-1 to the gateway 104-N for transmittal to the FC switch 102-3.
[0033] Figure 2 illustrates components of a first gateway and a second 10 gateway, such as the gateway 104-1 and the gateway 104-N, for establishing of a connection between FC switches, according to an embodiment of the present subject matter. In accordance with the present subject matter, the gateway 104-1 and the gateway 104-N are communicatively coupled to each other through the communication network 106 (as shown in Figure 1). 15
[0034] The gateway 104-1 and the gateway 104-N include processors 202-1, 202-2, collectively referred to as processor 202 hereinafter. The processor 202 may be implemented as one or more microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuitries, and/or any devices that manipulate signals based on operational instructions. Among 20 other capabilities, the processor(s) is configured to fetch and execute computer-readable instructions stored in a memory of the gateway 104-1 and the gateway 104-N.
[0035] The functions of the various elements shown in the figure, including any functional blocks labeled as “processor(s)”, may be provided through the use of 25 dedicated hardware as well as hardware capable of executing software in association with appropriate software. When provided by a processor, the functions may be
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provided by a single dedicated processor, by a single shared processor, or by a plurality of individual processors, some of which may be shared. Moreover, explicit use of the term “processor” should not be construed to refer exclusively to hardware capable of executing software, and may implicitly include, without limitation, digital signal processor (DSP) hardware, network processor, application specific integrated 5 circuit (ASIC), field programmable gate array (FPGA), read only memory (ROM) for storing software, random access memory (RAM), non-volatile storage. Other hardware, conventional and/or custom, may also be included.
[0036] Also, the gateway 104-1 and the gateway 104-N include I/O interface(s) 204-1, 204-2, collectively referred to as I/O interfaces 204. The I/O 10 interfaces 204 may include a variety of software and hardware interfaces that allow the gateway 104-1 and the gateway 104-N to interact with the FC switches 102, the communication network 106, and with each other. For example, as mentioned in the Figure 1, the gateways 104 include the TE_Ports 108 and the VE Ports 110. Further, the I/O interfaces 204 may enable the gateway 104-1 and the gateway 104-N to 15 communicate with other communication and computing devices, such as web servers and external repositories. The I/O interfaces 204 may facilitate multiple communications within a wide variety of networks and protocol types, including wire networks, for example, LAN, cable, etc., and wireless networks, for example, WLAN, cellular, satellite-based network, etc. 20
[0037] The gateway 104-1 and the gateway 104-N may include memory 206-1, and 206-2, respectively, collectively referred to as memory 206. The memory 206-1 and 206-2 may be coupled to the processor 202-1, and the processor 202-2, respectively. The memory 206 may include any computer-readable medium known in the art including, for example, volatile memory (e.g., RAM), and/or non-volatile 25 memory (e.g., EPROM, flash memory, etc.).
[0038] In one implementation, the gateway 104-1 and the gateway 104-N include modules 208-1, 208-2 and data 210-1, 210-2, respectively, collectively
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referred to as modules 208 and data 210, respectively. The module(s) 208, amongst other things, include routines, programs, objects, components, data structures, etc., which perform particular tasks or implement particular abstract data types. The module(s) 208 may also be implemented as, signal processor(s), state machine(s), logic circuitries, and/or any other device or component that manipulate signals based 5 on operational instructions.
[0039] Further, the modules 208 can be implemented in hardware, instructions executed by a processing unit, or by a combination thereof. The processing unit can comprise a computer, a processor, such as the processor 202, a state machine, a logic array or any other suitable devices capable of processing 10 instructions. The processing unit can be a general-purpose processor which executes instructions to cause the general-purpose processor to perform the required tasks or, the processing unit can be dedicated to perform the required functions.
[0040] In another aspect of the present subject matter, the modules 208 may be machine-readable instructions (software) which, when executed by a 15 processor/processing unit, perform any of the described functionalities. The machine-readable instructions may be stored on an electronic memory device, hard disk, optical disk or other machine-readable storage medium or non-transitory medium. In one implementation, the machine-readable instructions can be also be downloaded to the storage medium via a network connection. The data 210 serves, amongst other 20 things, as a repository for storing data that may be fetched, processed, received, or generated by one or more of the modules 208.
[0041] In an implementation, the modules 208-1 of the gateway 104-1 include a communication module 212-2, a frame conversion module 214-1 and other module(s) 216-1. In said implementation, the data 210-1 of the gateway 104-1 25 includes communication data 218-1, conversion data 220-1, and other data 224-1.
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[0042] Similarly, in an implementation, the modules 208-2 of the gateway 104-N include a communication module 212-2, a frame conversion module 214-2, and other module(s) 216-2. In said implementation, the data 210-2 of the gateway 104-N includes communication data 218-2, conversion data 220-2, and other data 224-2. The other module(s) 216-1 and 216-2 may include programs or coded 5 instructions that supplement applications and functions, for example, programs in the operating system of the gateway 104-1 and the gateway 104-2, respectively. The other data 224-1 and 224-2 comprise data corresponding to one or more other module(s) 216-1 and 216-2, respectively.
[0043] According to an implementation, the gateway 104-1 and the gateway 10 104-N may facilitate establishment of a connection between two FC switches, say a first FC switch and a second FC switch over a FCoE network. As described earlier in the Figure 1, prior to the establishment of the connection, the gateway 104-1 and the gateway 104-N may learn about each other's functionality of supporting establishment of the connection via FIP discovery mechanism. In said 15 implementation, the gateway 104-1 may store a source MAC address of the gateway 104-N in the communication data 218-1. Similarly, the gateway 104-N may store a source MAC address of the gateway 104-1 in the communication data 218-2.
[0044] In an implementation, the communication module 212-1 may receive an FC ELP frame from the first FC switch for establishing the connection with the 20 second FC switch. In said implementation, the frame conversion module 214-1 may then convert the FC ELP frame to a FIP ELP frame. For instance, the frame conversion module 214-1 may encapsulate the first FC ELP frame into a FIP ELP frame having a FIP header. Upon conversion of the FC ELP frame to the FIP ELP frame, the communication module 212-1 may transmit the FIP ELP frame to the 25 gateway 104-N over the FCoE network 106 for establishment of the connection with the second FC switch. The FIP ELP frame may be received by the communication module 212-2 in the gateway 104-N.
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[0045] Upon receiving the FIP ELP frame, the communication module 212-2 may store the FIP ELP frame in the communication data 218-2. The frame conversion module 214-2 may then convert the FIP ELP frame back to an FC technology compatible format prior to being sent to the second FC switch. In an example, the frame conversion module 214-2 may decapsulate the FIP header to obtain the FC 5 ELP frame. Further, the frame conversion module 214-2 may modify at least one port parameter of the FC ELP frame to obtain a new port parameter corresponding to the at least port parameter. As may be understood, the at least one port parameter may pertain to the first FC switch. Further, the new port parameter may correspond to the gateway 104-N. The communication module 212-2 may then transmit the FC ELP 10 frame to the second FC switch.
[0046] Upon receiving the FC ELP frame, the second FC switch may acknowledge the receipt of the FC ELP frame to the first FC switch. As may be understood, the acknowledgement may be suitably converted into compatible formats by the gateway 104 depending upon the media through which the acknowledgement 15 is to be transmitted. In an example, the second FC switch may either choose to accept or reject the FC ELP frame thereby accepting or rejecting the establishment of the connection with the first FC switch. In response to the FC ELP frame, the second FC switch may transmit a connection establishment response message indicative of an acceptance or rejection of the FC ELP frame to the communication module 212-2 for 20 transmittal to the first FC switch. In a case where the second FC switch ascertains to establish the connection, the connection establishment response message may include a SW_ACC frame. In another case where the second FC switch ascertains not to establish the connection, the connection establishment response message may include a SW_RJT frame. In an example, upon receiving the connection establishment 25 response message, the frame conversion module 214-2 may convert the connection establishment response message to the FCoE compatible format. For instance, in the case where the connection establishment response message includes the SW_ACC
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frame, the frame conversion module 214-2 may convert the SW_ACC frame to a FIP SW_ACC frame. Similarly, in the case where the connection establishment response message includes the SW_RJT frame, the frame conversion module 214-2 converts the SW_RJT frame to a FIP SW_RJT frame. Upon completion of the conversion, the communication module 212-2 may transmit the connection establishment response 5 message with the FIP SW_ACC/REJECT frame to the communication module 212-1.
[0047] Upon receiving the connection establishment response message, the communication module 212-1 may store the FIP SW_ACC/RJT in the conversion data 220-1. In an implementation, the frame conversion module 214-1 may then convert the FIP SW_ACC/REJECT frame to the FC technology compatible format. 10 The communication module 212-1 may then transmit the connection establishment response message including the FC SW_ACC/REJECT to the first FC switch.
[0048] Upon receiving the connection establishment response message, the first FC switch transmits an acknowledgement, similar to the acknowledgement received from the second FC switch, to the communication module 212-1 for 15 transmittal to the second FC switch. In a case where the connection establishment response message includes the FC SW_ACC frame, the connection between the first FC switch and the second FC switch is established. Subsequently, data traffic between the first FC switch and the second FC switch is transmitted over the communication network 106. 20
[0049] Figure 3 illustrates a method 300 for establishing a connection between FC switches, in accordance with an embodiment of the present subject matter. The order in which the method 300 is described is not intended to be construed as a limitation, and any number of the described method blocks can be combined in any order to implement the method 300, or an alternative method. 25 Additionally, individual blocks may be deleted from the method without departing from the spirit and scope of the subject matter described herein. Furthermore, the
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method can be implemented in any suitable hardware, software, firmware, or combination thereof.
[0050] The method(s) may be described in the general context of computer executable instructions. Generally, computer executable instructions can include routines, programs, objects, components, data structures, procedures, modules, 5 functions, etc., that perform particular functions or implement particular abstract data types. The method may also be practiced in a distributed computing environment where functions are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, computer executable instructions may be located in both local and remote computer storage 10 media, including memory storage devices.
[0051] A person skilled in the art will readily recognize that steps of the method 300 can be performed by programmed computers. Herein, some embodiments are also intended to cover program storage devices, for example, digital data storage media, which are machine or computer readable and encode machine-15 executable or computer-executable programs of instructions, wherein said instructions perform some or all of the steps of the described method. The program storage devices may be, for example, digital memories, magnetic storage media, such as a magnetic disks and magnetic tapes, hard drives, or optically readable digital data storage media. The embodiments are also intended to cover all the communication 20 networks and communication devices configured to perform said steps of the exemplary method.
[0052] At block 302, an FC ELP frame is received, by a gateway, from a first FC switch for establishing a connection with a second FC switch. In an example, the FC ELP frame may be received via an FC Port of the gateway. In said example, the 25 FC port of the gateway may be configured as a TE_Port. In an implementation, the gateway 104-1 may receive the FC ELP frame from the FC switch 102-1.
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[0053] At block 304, the FC ELP frame is converted to a FIP ELP frame for transmitting over a communication network. Upon receiving the FC ELP frame, the gateway may encapsulate the FC ELP frame in a FIP ELP header to obtain the FIP ELP frame. As may be understood, the conversion of the FC ELP to FIP ELP is performed to ensure that the FC ELP is in compliance with FCoE technology 5 supported by the communication network. In an example, the gateway 104-1 may convert the FC ELP frame to the FIP ELP frame.
[0054] At block 306, the FIP ELP frame is transmitted to the second FC switch. In an example, the gateway may send the FIP ELP packet through an Ethernet port of the gateway to another gateway. In said example, the Ethernet port may be 10 configured as a VE Port. In an example, the gateway and the other gateway may be configured on a same VLAN. Upon receiving the FIP ELP frame, the other gateway connected to the second FC switch may decapsulate the FIP ELP header of the FIP ELP frame to obtain the FC ELP frame. The other gateway may then transmit the FC ELP to the second FC switch. In an implementation, the gateway 104-1 may transmit 15 the FC ELP to the gateway 104-N for transmittal to the second FC switch.
[0055] At block 308, a connection establishment response message is received, by the gateway, from the second FC switch for establishing the connection. Upon receiving the FC ELP, the second FC switch may agree to establish the connection and may subsequently transmit the connection establishment response 20 message including an SW_ACC frame to the first FC switch. The connection establishment response message is suitably converted by the gateway connected to the second FC switch and the gateway connected to the first FC switch in a manner as described in the Figure 2 description. Upon receiving the connection establishment response message, the connection between the first FC switch and the second FC 25 switch is established. Thereafter, data traffic between the first FC switch and the second FC switch is transmitted.
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[0056] Although implementations for communication between FC switches have been described in a language specific to structural features and/or methods, it is to be understood that the appended claims are not necessarily limited to the specific features or methods described. Rather, the specific features and methods are disclosed as exemplary implementations for communication between FC switches.

I/We claim:
1. A method for establishing a connection between two Fibre Channel (FC) switches (102), the method comprising:
converting, by a first gateway (104), an FC Exchange Link Parameters (ELP) frame received from a first FC switch (102) to a Fibre Channel over 5 Ethernet (FCoE) Initialization Protocol (FIP) ELP frame, wherein the FC ELP frame is indicative of a request to establish a connection with a second FC switch (102);
transmitting, by the first gateway (104), the FIP ELP frame to a second gateway (104) over a communication network (106), wherein the second 10 gateway (104) is connected to the second FC switch (102); and
receiving, by the first gateway (104), a connection establishment response message from the second gateway (104) for establishing the connection between the first FC switch (102) and the second FC switch (102).
2. The method as claimed in claim 1, wherein the converting further comprises 15 encapsulating the FC ELP frame in a FIP ELP header to obtain the FIP ELP frame.
3. The method as claimed in claim 2, wherein the method further comprises:
receiving, by the second gateway (104), the FIP ELP frame from the first gateway (104) over the communication network (106); 20
decapsulating, by the second gateway (104), the FIP ELP header of the FIP ELP frame to obtain the FC ELP frame; and
transmitting, by the second gateway (104), the FC ELP frame to the second FC switch (102) for establishment of the connection.
4. The method as claimed in claim 1, wherein the first gateway (104) and the 25 second gateway (104) are configured on a same Virtual Local Area Network (VLAN).
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5. The method as claimed in claim 1, wherein the communication network (106) is an Ethernet based communication network (106) implementing Fibre Channel over Ethernet (FCoE) technology.
6. The method as claimed in claim 3, wherein the method further comprises
generating, by the second FC switch (102), the connection establishment 5 response message, wherein the connection establishment response message is at least one of a SW_ACC and a SW_RJT; and
transmitting the connection establishment response message to the second gateway (104) for transmittal to the first FC switch (102).
7. The method as claimed in claim 3, wherein the method further comprises 10 modifying, by the second gateway (104), at least one port parameter of the FC ELP frame to obtain a corresponding new port parameter, wherein the at least one port parameter pertains to the first FC switch (102) and the new port parameter pertains to the second gateway (104).
8. A gateway (104) comprising: 15
a processor (202);
a frame conversion module (214) coupled to the processor (202) to convert an FC Exchange Link Parameters (ELP) frame received from a first FC switch (102) to a Fibre Channel over Ethernet (FCoE) Initialization Protocol (FIP) ELP frame, wherein the FC ELP frame is indicative of a 20 request to establish a connection with a second FC switch (102); and
a communication module (212) coupled to the processor (202) to,
transmit the FIP ELP frame to another gateway (104) over a communication network (106), wherein the other gateway (104) is connected to the second FC switch (102); and 25
receive a connection establishment response message from the other gateway (104) for establishing the connection between the first FC switch (102) and the second FC switch (102).
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9. The gateway (104) as claimed in claim 8, wherein the frame conversion module (214) further is to encapsulate the FC ELP frame in a FIP ELP header to obtain the FIP ELP frame.
10. The gateway (104) as claimed in claim 8, wherein the gateway (104) and the other gateway (104) are configured on a same Virtual Local Area Network 5 (VLAN).
11. A gateway (104) comprising:
a processor (202);
a frame conversion module (214) coupled to the processor (202) to convert a Fibre Channel over Ethernet (FCoE) Initialization Protocol (FIP) 10 ELP frame received from another gateway (104) to an FC Exchange Link Parameters (ELP) frame, wherein the other gateway (104) is connected to a first FC switch, and wherein the FC ELP frame is indicative of a request to establish a connection with a second FC switch (102) connected to the gateway (104); and 15
a communication module (212) coupled to the processor (202) to transmit a connection establishment response message received from the second FC switch (102) to the other gateway (104) for transmission to the first FC switch (102), wherein the connection response message indicates one of an acceptance and a rejection to establish the connection with the first FC 20 switch (102).
12. The gateway (104) as claimed in claim 11, wherein the communication module (212) further is to transmit the FIP ELP frame to the second FC switch (102).
13. The gateway as claimed in claim 11, wherein the frame conversion module 25 (214) further is to,
decapsulate a FIP ELP header of the FIP ELP frame to obtain the FC ELP frame; and
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modify at least one port parameter of the FC ELP frame to obtain a corresponding new port parameter, wherein the at least one port parameter pertains to the first FC switch (102) and the new port parameter pertains to the gateway (104).
14. The gateway (104) as claimed in claim 11, wherein the gateway (104) and the 5 other gateway (104) are configured on a same Virtual Local Area Network (VLAN).
15. A non-transitory computer-readable medium having embodied thereon a computer program for executing a method comprising:
converting, by a first gateway (104), an FC Exchange Link Parameters 10 (ELP) frame received from a first FC switch (102) to a Fibre Channel over Ethernet (FCoE) Initialization Protocol (FIP) ELP frame, wherein the FC ELP frame is indicative of a request to establish a connection with a second FC switch (102); and
transmitting, by the first gateway (104), the FIP ELP frame to a second 15 gateway (104) over a communication network (106), wherein the second gateway (104) is connected to the second FC switch (102); and
receiving, by the first gateway (104), a connection establishment response message from the second gateway (104) for establishing the connection between the first FC switch (102) and the second FC switch (102).