FC protocol predominantly is the implementation of SCSI over an FC network. SCSI data is encapsulated and transported within FC frames. SCSI over FC overcomes the distance and the scalability limitations associated with traditional direct-attached storage.
Full Answer
What is the FC protocol architecture?
The FC architecture represents true channel and network integration and captures some of the benefits of both channel and network technology. FC protocol provides both the channel speed for data transfer with low protocol overhead and the scalability of network technology.
What is FC (Fibre Channel)?
What is Fibre Channel? FC (Fibre Channel) is a network technology, predominantly used within storage area networks, to provide high-speed, loss-less delivery of raw block data between computer data storage and server devices.
What is FC-2 signaling protocol?
FC-2 – Signaling Protocol, defined by the Fibre Channel Framing and Signaling 4 (FC-FS-5) standard, consists of the low level Fibre Channel network protocols; port to port connections; FC-0 – physical layer, includes cabling, connectors etc.; This diagram from FC-FS-4 defines the layers.
What is the difference between FC and FCP switches?
FC Switches - High-speed Fibre Channel switches. The FCP (Fibre Channel Protocol) operates over the FC fabric. Predominantly FCP is the implementation of SCSI over an FC network, or in other words, SCSI data is encapsulated and transported within FC frames.
What is the FCP protocol?
What is FC frame?
How many bits are in FC?
How many words are allowed in FC?
What does SOF mean?
What is routing control?
Is Fibre Channel a replacement for SCSI?
See 2 more
How does FC work?
How FC Works on the Switch. The switch connects devices that support FC and Ethernet (such as FCoE servers on an Ethernet network) to an FC SAN, thus converging the Ethernet and FC networks on a single physical network infrastructure.
Is FC a protocol?
Fibre Channel (FC) is a high-speed data transfer protocol providing in-order, lossless delivery of raw block data. Fibre Channel is primarily used to connect computer data storage to servers in storage area networks (SAN) in commercial data centers.
What protocol does Fibre Channel use?
Fibre Channel Protocol (FCP)Fibre Channel is a gigabit-speed network technology used for block-based storage. The Fibre Channel Protocol (FCP) is the interface protocol used to transmit SCSI on this network technology.
What is FC in networking?
Fibre Channel (FC) is a serial I/O interconnect network technology capable of supporting multiple protocols. It is used primarily for storage area networks (SANs). The committee standardizing FC is the International Committee for Information Technology Standards (INCITS).
What is FC architecture?
Fibre Channel architecture provides various communication protocols on the storage system. The storage systems that are interconnected are referred to as nodes . Each node has one or more ports . A storage system is a node in a Fibre Channel network.
Why is FC lossless?
Fibre Channel switches operate lossless without dropping a single frame, and all the data frames are transmitted in order. This is because FC switches will stop sending frames lest they are dropped when congesting to other devices.
What is FC port?
A Fibre Channel port is a port on the storage system that connects it to hosts, switches, or another storage system either directly or through a switch. Fibre Channel ports are also referred to as I/O ports.
How fast is FC?
Fibre Channel is a high-speed networking technology primarily used for transmitting data among data centers, computer servers, switches and storage at data rates of up to 128 Gbps.
What is FC drive?
Fibre Attached Technology Adapted (FATA) or FC-ATA is a type of computer hard disk drive. FATA is simply a low cost ATA or SATA disk drive equipped with a small external converter, that bridges the interface to Fibre Channel (FC).
Which networks are included in FC topologies?
Fibre Channel Topologies. One of Fibre Channels most admired features is its' flexible topology. Fibre Channel includes three connection methods; Point-to-Point, Arbitrated Loop, and Switched Fabric.
How does Fibre Channel storage work?
Fibre Channel typically runs on optical fiber cables within and between data centers but can also run on copper cabling. Fibre Channel is a high-speed data transfer protocol that provides in-order, lossless delivery of raw block data to connect data storage to host servers.
Who determines the WWN of FC End Point *?
WWNs provide a method for identifying FC devices across the network. Each WWN conforms to one of several formats defined by the Institute of Electrical and Electronic Engineers (IEEE).
Which protocol used for IP storage replication?
If you use IP replication, TCP ports 3260 and 3265 must be available for IP partnership communications. Port 3260 is used by systems to initially discover each other. Port 3265 is used for IP replication sessions that are used to transmit data.
Which protocol does Fibre channel protocol encapsulate on a FC SAN?
The FCP (Fibre Channel Protocol) operates over the FC fabric. Predominantly FCP is the implementation of SCSI over an FC network, or in other words, SCSI data is encapsulated and transported within FC frames.
What is iSCSI protocol?
iSCSI is a block protocol for storage networking and runs the very common SCSI storage protocol across a network connection which is usually Ethernet. iSCSI, like Fibre Channel, can be used to create a Storage Area Network (SAN). iSCSI traffic can be run over a shared network or a dedicated storage network.
What is FCIP FCIP protocol stack?
Fibre Channel over IP, or FCIP, is a tunnelling protocol used to connect Fibre Channel (FC) switches over an IP network, enabling interconnection of remote locations. From the fabric view, an FCIP link is an inter-switch link (ISL) that transports FC control and data frames between switches.
Figure 558 Fibre Channel Frame Header Format - Network Layer
• Data field— The data field consists of the actual upper-layer protocol data. It can range from 0 to 2112 bytes. • CRC— The Cyclical Redundancy Check is a 4-byte field used to verify the frame's integrity.
Fibre Channel Specifications - CERN
ANSI Fibre Channel specifications The ANSI working group X3T11 defines the Fibre Channel specifications. The Fibre Channel Association has a complete list of the ANSI X3T11 Fibre Channel Standards and draft Standards You can find those via the FCA Fibre Channel Technology pages (click on Standards at the top of that page).
Fibre Channel Protocol - an overview | ScienceDirect Topics
Caesar Wu, Rajkumar Buyya, in Cloud Data Centers and Cost Modeling, 2015. 12.4.2.7 Internet Fibre Channel Protocol (iFCP). Along with FCIP development, the IETF also developed anther protocol called the Internet Fibre Channel Protocol (iFCP). The initial goal of iFCP was to replace both FC-SW and SAN with Fibre Channel (FC) over IP network, or simply an IP network.
What is the FCP protocol?
Fibre Channel Protocol (FCP) is a protocol that transports SCSI commands over Fibre Channel networks. FICON is a protocol that transports ESCON commands, used by IBM mainframe computers, over Fibre Channel. Fibre Channel can be used to transport data from storage systems that use solid-state flash memory storage medium by transporting NVMe protocol commands.
Why do fiber channels form a switched fabric?
Fibre Channel networks form a switched fabric because the switches in a network operate in unison as one big switch. Fibre Channel typically runs on optical fiber cables within and between data centers, but can also run on copper cabling.
What is QSFP in a switch?
The quad small form-factor pluggable (QSFP) module began being used for switch inter-connectivity and was later adopted for use in 4-lane implementations of Gen 6 Fibre Channel supporting 128GFC. The QSFP uses either the LC connector for 128GFC-CWDM4 or an MPO connector for 128GFC-SW4 or 128GFC-PSM4. The MPO cabling uses 8- or 12-fiber cabling infrastructure that connects to another 128GFC port or may be broken out into four duplex LC connections to 32GFC SFP+ ports. Fibre Channel switches use either SFP or QSFP modules.
What type of connector is used in 128GFC?
Fibre Channel predominantly uses the SFP module with the LC connector and duplex cabling, but 128GFC uses the QSFP28 module and the MPO connectors and ribbon cabling.
What is SFP+?
The small form-factor pluggable transceiver (SFP) module and its enhanced version SFP+, SFP28 and SFP56 are common form factors for Fibre Channel ports. SFP modules support a variety of distances via multi-mode and single-mode optical fiber as shown in the table below. The SFP module uses duplex fiber cabling that has LC connectors.
What is open fabric mode?
This is called the "open fabric" mode as each vendor's switch may have to disable its proprietary features to comply with the Fibre Channel standard.
How many layers does the fibre channel have?
Fibre Channel does not follow the OSI model layering, and is split into five layers:
What is the FCP protocol?
The term FCP, Fibre Channel Protocol, refers to the interface protocol for SCSI, or the FC-4 mapping. We’re talking about the inner-workings of FC here, not FCP. FC data units are called Frames. FC is mostly a layer 2 protocol, even though it has its own layers. The maximum size for an FC frame is 2148 bytes, and the header FC frame itself is ...
What is FC frame?
FC frames begin with a start-of-frame (SOF) marker followed by frame the header, which will be described in a moment. The data, or FC content, comes next, followed by an EOF. The reason for the encapsulation is so that FC can be carried over other protocols, such as TCP if desired.
How many bytes are in a FC frame?
The maximum size for an FC frame is 2148 bytes, and the header FC frame itself is a bit strange, at least when compared to Ethernet with IP and TCP. FC uses one frame format for many purposes, and at many layers.
How many bits are in FC?
The next important concept to grasp is the way FC assigns names. Notice that the D_ID and S_ID fields in the FC Frame Header only allow for 24 bits. Each HBA is assigned a WWN, and each port on it is assigned a Port WWN, or PWWN. These WWNs are 64-bits in length, which are larger than the 24 bits in FC. The ANSI T11 Address Identifier Format says that the FCID is made up of three parts, which are the Domain_ID, the Area_ID, and the Port_ID.
How many words are allowed in FC?
The strange part about FC headers is that they are word-oriented, and an FC word is 4 bytes. Up to 537 words are allowed, which gives us our 2148-byte capacity.
What does SOF mean?
SOF (1 word): The start of a frame.
What is routing control?
Routing Control (1 byte): The routing portion says if this is a data frame or a link-control frame (either an ACK or a Link_Response), and the information portion indicates the type of data.
What is a FCP switch?
FC Switches - High-speed Fibre Channel switches. The FCP (Fibre Channel Protocol) operates over the FC fabric. Predominantly FCP is the implementation of SCSI over an FC network, or in other words, SCSI data is encapsulated and transported within FC frames. [1]
What is FC addressing?
FC addressing is based upon WWN (World Wide Names). These addresses are unique to each of the FC devices (such as an FC HBA or SAN's) and are 64-bit addresses, consisting of 16 x Hexadecimal values, like so: 15:00:00:f0:8c:08:95:de.
What is Fibre Channel?
FC (Fibre Channel) is a network technology, predominantly used within storage area networks, to provide high-speed, loss-less delivery of raw block data between computer data storage and server devices.
What is a fibre channel name service?
The Fibre Channel Name Service (FCNS) is used to exchange the FLOGI database, between switches within the fabric. Allowing each switch to learn where each WWPN is, and how to route traffic there. [10]
What is a FLOGI request?
When a device is connected to the fabric, it sends a Fabric Login (FLOGI) request. The switch assigns a 24-bit FCID address, which is equivalent to an IP address.
What is FC-0 cable?
FC-0 - Defines the physical media used to link two Fibre Channel ports, including cabling types, optical and electrical parameters for a variety of data rates, maximum transfer distances, and noise limits. Fibre Channel supports two types of cables: Copper and optical. [2]
How many layers are there in the fibre channel?
Instead, it is broken down into 5 layers. As shown below:
What is FC protocol?
FC protocol forms the fundamental construct of the FC SAN infrastructure. FC protocol predominantly is the implementation of SCSI over an FC network. SCSI data is encapsulated and transported within FC frames.
How does FC work in fabric?
In a fabric, an FC frame is received and stored in a receive buffer where it is processed by the receiving FC port. If another frame arrives while the receiving port is processing the first frame, a second receive buffer is needed to hold the new frame. If all the receive buffers are filled up with received frames and the transmitting port sends another frame, then the receiving port would not have a receive buffer available to hold the new frame and the frame would be dropped. BB_Credit mechanism ensures that the FC ports do not run out of buffers and do not drop frames.
How to log in to Fabric Login?
Fabric login (FLOGI): It is performed between an N_Port and an F_Port. To log on to the fabric, a node sends a FLOGI frame with the WWNN and WWPN parameters to the login service at the predefined FC address FFFFFE (Fabric Login Server). In turn, the switch accepts the login and returns an Accept (ACC) frame with the assigned FC address for the node. Immediately after the FLOGI, the N_Port registers itself with the local Name Server on the switch, indicating its WWNN, WWPN, port type, class of service, assigned FC address, and so on. After the N_Port has logged in, it can query the name server database for information about all other logged in ports.
What is SCSI over FC?
SCSI over FC overcomes the distance and the scalability limitations associated with traditional direct-attached storage. Storage devices attached to the FC SAN appear as locally attached devices to the operating system (OS) or hypervisor running on the compute system.
How does BB_Credit work?
With BB_Credit mechanism, the transmitting and receiving ports agree on the number of buffers available or BB_Credits during the port login process. The credit value is decremented when a frame is transmitted and incremented upon receiving a response. A receiver ready (R_RDY) is sent from the receiving port to the transmitting port for every free buffer on the receiving side. The transmitting port increments the credit value per R_RDY it receives from the receiving port. The transmitting port maintains a count of available credits and continues to send frames if the count is greater than zero. If the available credits reaches zero, then further transmission of frames is suspended until the credit count becomes a nonzero value.
What is FC address?
The first field of the FC address contains the domain ID of the switch. A domain ID is a unique number provided to each switch in the fabric. Although this is an 8-bit field, there are only 239 available addresses for domain ID because some addresses are deemed special and reserved for fabric services. For example, FFFFFC is reserved for the name server, and FFFFFE is reserved for the fabric login service.
What is a fabric switch?
A fabric is a collection of connected FC switches that have a common set of services such as they can share a common name server, common zoning database and common FSPS routing table. You can also deploy dual redundant fabrics for resiliency. Each fabric is viewed and managed as a single logical entity and it is common across the fabric to update the zoning configuration from any switch in the fabric.
What is the IFCP protocol?
Along with FCIP development, the IETF also developed anther protocol called the Internet Fibre Channel Protocol (iFCP). The initial goal of iFCP was to replace both FC-SW and SAN with Fibre Channel (FC) over IP network, or simply an IP network. In essence, it is a specification that defines the communication protocol from one iFCP gateway to another iFCP gateway over the IP network for existing FC components. The protocol allows existing FC storage components to be directly attached to an IP network. From a protocol stack perspective, iFCP replaces the FC network’s transport layer (FC-2) with an IP network (or Ethernet) transport layer, but still supports upper layer information (see Figure 12.50 ).
What happens after the initiator issues a SCSI FCP write?
After the initiator issues an SCSI FCP write, an FCP_XFER_RDY is immediately returned to the initiator by the MDS switch (proxying as the target to the initiator).
What is FCIP write acceleration?
FCIP write acceleration is an SCSI protocol-spoofing mechanism that is designed to improve application performance by reducing the overall service time for SCSI write I/Os and replicated write I/Os over distance. The FCIP write acceleration spoofs XFER_RDY:
What is iFCP gateway?
The key component of this solution is the iFCP gateway, which connects existing FC devices, such as FC HBA, and an IP network (see Figure 12.53 ). By leveraging the iFCP gateway, we can eliminate the FC switch fabric network. Ultimately, this is a consolidation solution. The idea behind this initiative is to reduce the total cost of ownership (TOC) by integrating two different networks into one IP network.
What is the difference between the top and bottom diagrams of SCSI?
In Figure 7.18, the top diagram illustrates a normal SCSI write operation without write acceleration while the bottom diagram shows the SCSI write operation with write acceleration.
Why use SAN in Exchange?
This is the reason why almost all new infrastructures use the storage network to send data from the Exchange server to the backup library.
Does FCIP write acceleration reduce latency?
This issue is even more obvious for applications that limit the number of outstanding I/O operations, such as tape backup. The number of FCIP WAN round-trips per SCSI FCP write are reduced with FCIP write acceleration.
Which part of the antibody molecules interacts with a plethora of immune cells?
In contrast, it is the common Fc part of the antibody molecules that interacts with a plethora of immune cells (such as B lymphocytes, dendritic cells, monocytes, macrophages, NKs, neutrophils, eosinophils, human platelets, mast cells and basophils) responsible for the in vivo observed effector functions. These cells express a variety of Fc ...
Does fetal bovine serum block Fc receptors?
Note that fetal bovine serum commonly included in the staining buffer recipes has too low IgG content and will not block the Fc receptors. Isotype controls (labeled antibodies with irrelevant specificity) can be used to evaluate the effectiveness of the Fc blocking protocol.
Can antibodies be blocked by recombinant detection?
Fab fragments, REAfinity™ antibodies), or more commonly, be blocked by saturating the receptors prior to staining the cells with labeled antibodies.
What is a FCF switch?
FCoE Fibre Channel Forwarder (FCF) is a logical Fibre Channel switch within the F CoE switch. FCoE frames are forwarded, by the FCF, based on the FC Destination_ID (D_ID) field within the FCoE frame.
What is fiber channel?
Fibre Channel is a lossless protocol, that uses buffer-to-buffer credits to ensure that frames between the initiator and the target are not lost.
What is FCoE?
Fibre Channel over Ethernet ( FCoE) is a computer network technology that encapsulates Fibre Channel frames over Ethernet networks. This allows Fibre Channel to use 10 Gigabit Ethernet networks (or higher speeds) while preserving the Fibre Channel protocol. [1]
Why is FIP snooping required?
FIP snooping is required in order to prevent man in the middle types of attacks by allowing the lossless Ethernet switches to Dynamically update ACLs and only allow the ENode that performed FIP to transmit frames. [8]
What is QCN in traffic?
QCN (IEEE 802.1 Qau) allows for end-to-end congestion control. Congestion is measured at the congestion point, and if congestion is encountered, rate limiting, or back pressure, is imposed at the reaction point to shape traffic and reduce the effects of the congestion on the rest of the network. [5]
Is FCoE forwarding Ethernet?
Although FCoE frames are transported over Converged Enhanced Ethernet networks, the forwarding of FCoE frames is not the responsibility of Ethernet forwarding. Instead, FCoE forwarding is the responsibility of a function in the FCoE switch known as the FCoE Forwarder (FCF). [6]
What is HTTP protocol?
Hypertext Transfer Protocol provides a network protocol standard that web browsers and servers use to communicate. You see HTTP when you visit a website because the protocol appears in the URL (for example, http://www.lifewire.com). This protocol is similar to others, like file transfer protocol, in that it's used by a client program ...
How does HTTP work?
HTTP is an application layer protocol built on top of TCP that uses a client-server communication model. HTTP clients and servers communicate through request and response messages. The three main HTTP message types are GET, POST, and HEAD. HTTP GET: Messages sent to a server contain only a URL.
What happens after a session is established?
After a session is established, you trigger the sending and receiving of HTTP messages by visiting the web page. HTTP is what's called a stateless system. This means that, unlike other file transfer protocols such as FTP, the HTTP connection is dropped after the request completes.
What is HTTP in web browser?
In the case of HTTP, a web browser requests HTML files from a web server, which then display in the browser with text, images, hyperlinks, and related assets. Because browsers communicate using HTTP, you can usually drop the protocol from a URL when you type it in the browser's address bar.
Does HTTPS encrypt traffic?
It maintains backward compatibility with HTTP 1.1 but offers additional performance enhancements. While standard HTTP does not encrypt traffic sent over a network, the HTTPS standard adds encryption to HTTP through the use of Secure Sockets Layer or, later, Transport Layer Security.
What is the FCP protocol?
The term FCP, Fibre Channel Protocol, refers to the interface protocol for SCSI, or the FC-4 mapping. We’re talking about the inner-workings of FC here, not FCP. FC data units are called Frames. FC is mostly a layer 2 protocol, even though it has its own layers. The maximum size for a FC frame is 2148 bytes, and the header FC frame itself is ...
What is FC frame?
FC frames begin with a start-of-frame (SOF) marker followed by frame the header, which will be described in a moment. The data, or FC content, comes next, followed by an EOF. The reason for the encapsulation is so that FC can be carried over other protocols, such as TCP if desired.
How many bits are in FC?
The next important concept to grasp is the way FC assigns names. Notice that the D_ID and S_ID fields in the FC Frame Header only allow for 24 bits. Each HBA is assigned a WWN, and each port on it is assigned a Port WWN, or PWWN. These WWNs are 64-bits in length, which are larger than the 24 bits in FC. The ANSI T11 Address Identifier Format says that the FCID is made up of three parts, which are the Domain_ID, the Area_ID, and the Port_ID.
How many words are allowed in FC?
The strange part about FC headers is that they are word-oriented, and an FC word is 4 bytes. Up to 537 words are allowed, which gives us our 2148-byte capacity.
What does SOF mean?
SOF (1 word): The start of a frame.
What is routing control?
Routing Control (1 byte): The routing portion says if this is a data frame or a link-control frame (either an ACK or a Link_Response), and the information portion indicates the type of data.
Is Fibre Channel a replacement for SCSI?
To reiterate: Fibre Channel is not a replacement for SCSI; SCSI generally rides on top of Fibre Channel. Now that we have that out of the way, let us get to work. FC generally refers to the FC-PHY layers: FC0-FC2, which were briefly discussed in our last installment.
Overview
Fibre Channel (FC) is a high-speed data transfer protocol providing in-order, lossless delivery of raw block data. Fibre Channel is primarily used to connect computer data storage to servers in storage area networks (SAN) in commercial data centers.
Fibre Channel networks form a switched fabric because the switches in a network operate in unison as one big switch. Fibre Channel typically runs on optical fiber cables within and between …
Etymology
When the technology was originally devised, it ran over optical fiber cables only and, as such, was called "Fiber Channel". Later, the ability to run over copper cabling was added to the specification. In order to avoid confusion and to create a unique name, the industry decided to change the spelling and use the British English fibre for the name of the standard.
History
Fibre Channel is standardized in the T11 Technical Committee of the International Committee for Information Technology Standards (INCITS), an American National Standards Institute (ANSI)-accredited standards committee. Fibre Channel started in 1988, with ANSI standard approval in 1994, to merge the benefits of multiple physical layer implementations including SCSI, HIPPI and ESCON.
Characteristics
Two major characteristics of Fibre Channel networks are in-order delivery and lossless delivery of raw block data. Lossless delivery of raw data block is achieved based on a credit mechanism.
Topologies
There are three major Fibre Channel topologies, describing how a number of ports are connected together. A port in Fibre Channel terminology is any entity that actively communicates over the network, not necessarily a hardware port. This port is usually implemented in a device such as disk storage, a Host Bus Adapter (HBA) network connection on a server or a Fibre Channel switch.
Layers
Fibre Channel does not follow the OSI model layering, and is split into five layers:
• FC-4 – Protocol-mapping layer, in which upper level protocols such as NVM Express (NVMe), SCSI, IP, and FICON are encapsulated into Information Units (IUs) for delivery to FC-2. Current FC-4s include FCP-4, FC-SB-5, and FC-NVMe.
• FC-3 – Common services layer, a thin layer that could eventually implement functions …
Ports
Fibre Channel ports come in a variety of logical configurations. The most common types of ports are:
• N_Port (Node port) An N_Port is typically an HBA port that connects to a switch's F_Port or another N_Port. Nx_Port communicating through a PN_Port that is not operating a Loop Port State Machine.
Media and modules
The Fibre Channel physical layer is based on serial connections that use fiber optics to copper between corresponding pluggable modules. The modules may have a single lane, dual lanes or quad lanes that correspond to the SFP, SFP-DD and QSFP form factors. Fibre Channel has not used 8 or 16 lane modules (like CFP8, QSFP-DD, or COBO) used in 400GbE and has no plans to use these expe…
What Is Fibre Channel?
FC Layers
- Fibre Channel is primarily used for transmitting data and is a high-speed networking technology. It transmits data between storage, computer servers, switches, and data centers. Information units and SCSI commands are transmitted by Fibre Channel Protocol (FCP) within the Fibre Channel. Point-to-Point, Switched Fabric and Arbitrated Loop interfaces...
FC Frames
Addressing/Naming
Security
- When it comes to learning the various layers of Fibre Channel it is important to understand that FC does not follow the traditional OSI 7 layer model. Instead, it is broken down into 5 layers. As shown below: FC-0- Defines the physical media used to link two Fibre Channel ports, including cabling types, optical and electrical parameters for a variety of data rates, maximum transfer dis…
Login Processes
- Fibre Channel defines a variable length frame consisting of 36 bytes of overhead and up to 2112 bytes of payload for a total maximum size of 2148 bytes. A Start of Frame (SOF) delimiter and End of Frame (EOF) delimiter mark the beginning and end of each Fibre Channel frame. The CRC is used to detect transmission errors. Figure 2: FC Layers.
Ports/Links
- Aliases
Aliases are used to aid in the configuration and troubleshooting, by mapping the World Wide name (from the FC switch or storage system) to a string. For example: the WWPN 15:00:00:f0:8c:08:95:de could be aliased to MAIL-SERVER. - Switch Domain IDs
Within the FC network, each switch is assigned a unique Domain ID. A principle switch is elected within the network which assigns the Domain IDs to the other switches. This Domain ID is then used to form part of the FCID, as per the FLOGI process (described later).
Classes of Service
- Zoning
Zoning is a security feature that allows the administrator to control which hosts can communicate with each other. This allows the administrator to create zones that prevent servers from communicating with each other over the fabric, ensuring that each server can only communicat… - LUN Masking
LUN masking is used to restrict which LUN is presented to which host or set of hosts. This prevents unauthorized hosts from accessing LUNs and also prevents situations of data corruption that could occur should a host access the wrong LUN.
Flow Control
- Fabric Login
When a device is connected to the fabric, it sends a Fabric Login (FLOGI) request. The switch assigns a 24-bit FCID address, which is equivalent to an IP address. The FCID is then used by the FC switches to route traffic across the fabric. In addition, as part of this process buffer credits ar… - Port Login
Once the FLOGI is complete, the initiator will send the PLOGI request to the switch, in order to inform the Fabric Name Server (FCNS) of its personality and capabilities. Such as: 1. WWNN, WWPN 2. Buffer credits for flow control 3. clock frequency ('speed capability') 4. Upper layer prot…