1 6/22/ :39 Chapter 9Fiber Channel1 Rivier College CS575: Advanced LANs Chapter 9: Fibre Channel

2 6/22/ :39 Chapter 9Fiber Channel2 Fibre Channel Architecture, Media & Topologies 0 Fibre Channel Elements 0 Fibre Channel Protocol Architecture 0 Fibre Channel Transmission Media 0 Fibre Channel Topologies 0 Framing Protocol: * Classes of Service * Frames, Sequences, and Exchanges * Frame Control * Frame Format

3 6/22/ :39 Chapter 9Fiber Channel3 LAN Technology Comparison

4 6/22/ :39 Chapter 9Fiber Channel4 Fibre Channel Architecture: Requirements [FCA98] 0 Full-duplex links with two fibers per link 0 Performance from 100 Mbps to 3.2 Gbps on a single link results in 200 Mbps to 6.4 Gbps per link 0 Support for distance up to 10 km 0 Small connectors 0 High-capacity utilization with distance insensitivity 0 Greater connectivity than existing multidrop channels 0 Broad availability (i.e., standard components) 0 Support for multiple cost/performance levels, from small systems to supercomputers 0 Ability to carry multiple existing interface command sets for existing channel and network protocols

5 6/22/ :39 Chapter 9Fiber Channel5 Fibre Channel Terms

6 6/22/ :39 Chapter 9Fiber Channel6 Fibre Channel Terms (continued)

7 6/22/ :39 Chapter 9Fiber Channel7 Fibre Channel Elements: Port Types

8 6/22/ :39 Chapter 9Fiber Channel8 Fibre Channel Network

9 6/22/ :39 Chapter 9Fiber Channel9 Fibre Channel Protocol Architecture Levels

10 6/22/ :39 Chapter 9Fiber Channel10 Fibre Channel Levels Functionality

11 6/22/ :39 Chapter 9Fiber Channel11 Structure of Fiber Optic Cables Source: Decusatis: Handbook of Fiber Optic

12 6/22/ :39 Chapter 9Fiber Channel12 Structure of Fiber Optic Cables (concluded)

13 6/22/ :39 Chapter 9Fiber Channel13 Three Types of Fibers

14 6/22/ :39 Chapter 9Fiber Channel14 Multimode Fiber Source: Decusatis: Handbook of Fiber Optic

15 6/22/ :39 Chapter 9Fiber Channel15 Single Mode Fiber Source: Decusatis: Handbook of Fiber Optic

16 6/22/ :39 Chapter 9Fiber Channel16 Light Source Source: Decusatis: Handbook of Fiber Optic

17 6/22/ :39 Chapter 9Fiber Channel17 Fiber Optic Attenuation Source: Decusatis: Handbook of Fiber Optic

18 6/22/ :39 Chapter 9Fiber Channel18 Level FC-2: Framing Protocol 0 Transmission of data between N_Ports in terms of frames 0 Node and N_Port and their identifiers 0 Topologies 0 Classes of service provided by the fabric 0 Segmentation of data into frames and reassembly 0 Grouping of frames into logical entities called sequences and exchanges 0 Sequencing, flow control, and error control

19 6/22/ :39 Chapter 9Fiber Channel19 FC-3: Common Services 0 Common services across multiple N_Ports of a node. 0 Stripping Service makes use of multiple N_Ports in parallel to transmit a single information unit across multiple links simultaneously (i.e, transferring large data sets in real time, as video-imaging applications). 0 Hunt group is a set of associated N_Ports at a single node. This set is assigned an alias identifier that allows any frame sent to this alias to be routed to any available N_Port within the set. This may decrease latency by decreasing the chance of waiting for a busy N_Port. 0 Multicast delivers a transmission to multiple destinations. This includes sending to all N_Ports on a fabric (broadcast) or to a subset of the N_Ports on a fabric.

20 6/22/ :39 Chapter 9Fiber Channel20 FC-4: Mapping/ Interfaces 0 Mapping of various channel and network protocols to FC-PH. 0 Small computer system interface (SCSI) that is high-speed interface typically implemented on PCs, workstations, and servers. SCSI is used to support high-capacity and high-data-rate devices, such as disks and graphics and video equipment. 0 High-performance parallel interface (HIPPI) that is a high-speed channel standard used for mainframe/supercomputer environments. It was viewed as a possible general-purpose high-speed LAN solution, but HIPPI has been superseded by Fibre Channel. 0 Network IEEE 802 interface maps IEEE 802 MAC frames onto Fibre Channel frames. 0 Asynchronous Transfer Mode (ATM) network interface (Ch. 11). 0 Interface to Internet Protocol (Ch. 3). 0 Each FC-4 specification defines the formats and procedures for Upper-Level Protocol (ULP) level.

21 6/22/ :39 Chapter 9Fiber Channel21 Maximum Distance for Fibre Channel Media Types

22 6/22/ :39 Chapter 9Fiber Channel22 FC-0 Nomenclature

23 6/22/ :39 Chapter 9Fiber Channel23 Basic Fibre Channel Topologies

24 6/22/ :39 Chapter 9Fiber Channel24 Five Applications of Fibre Channel

25 6/22/ :39 Chapter 9Fiber Channel25 Framing Protocol: Classes of Service 0 FC-2 Framing Protocol 0 Defines the rules for exchange of higher-layer information between nodes. 0 Specifies types of frames, procedures for their exchange, and formats. 0 Is similar to the data link layer functions of the OSI model. 0 Classes are determine by the way communication is established between two ports and on the flow control and error control features of the communications channel. 0 Class 1: Acknowledged Connection Service 0 Class 2: Acknowledged Connectionless Service 0 Class 3: Unacknowledged Connectionless Service 0 Class 4: Fractional Bandwidth Connection-Oriented Service 0 Class 6: Unidirectional Connection Service

26 6/22/ :39 Chapter 9Fiber Channel26 Data Frames 0 Traffic between N_Ports over Fibre Channel is in the form of a stream of frames. 0 Two general categories of frames: Data frames transfer higher-level information between source and destination N-Ports; and link control frames are used to manage frame transfer and to provide some control for FC-2 Class 1 and Class 2 services. 0 FC-4 Device Data Frame is used to transfer higher-layer data units from supported FC-4 protocols, such as IEEE 802, SCSI, and IP. 0 FC-4 Video Data Frames are transferred by N_Port directly to or from a video buffer without first directing them to an intermediate storage location. 0 Link Data Frames are used to transfer link application information between N_Ports. This type of frame supports a control function of a higher level, such as the transmission of abort sequences, echo, and termination of Class 1 connections.

27 6/22/ :39 Chapter 9Fiber Channel27 Link Control Frames 0 Link Continue (Acknowledge) Frame is used in various Fibre Channel sliding-window flow control mechanisms to report successful delivery. 0 Fibre Response Frame is used in various Fibre Channel sliding- window flow control mechanisms to report unsuccessful delivery. 0 Link Command Frame is used as a reset command to reinitialize the sliding-window scheme.

28 6/22/ :39 Chapter 9Fiber Channel28 Common Protocols defined in Fibre Channel 0 Fabric Login Protocol is executed upon initialization of an N_Port. It enables the N_Port to exchange operational and configuration information with the fabric, such as the address assigned to the N_Port, classes of service supported, and credit for buffer-to-buffer flow control. 0 N-Port Login Protocol supports the N_Port interchange of its service parameters with another N_Port BEFORE performing data transfer. Service parameters include amount of buffer space available for data transfer, total number of concurrent sequences that N_Port can support as a recipient, and supported service classes. 0 Data Transfer Protocol defines the transfer of upper-layer protocol data between N_Ports. 0 N-Port Logout Protocol is used to terminate a connection to another N_Port. This request may be used to free resources at the two N_Ports.

29 6/22/ :39 Chapter 9Fiber Channel29 Flow Control Categories in Fibre Channel 0 End-to-End Flow Control is used between two communicating N_Ports. Each of the two N_Ports in communication provides credit for a certain number of frames. This is the only type of flow control available on dedicated connections after the first frame. 0 Buffer-to-Buffer Flow Control is used between two ports connected by a single point-to point link. This type of flow control regulates traffic between an N_Port and F_Port to which it is attached. 0 The concept of credit is critical for both flow control mechanisms. Prior to communication between two N_Ports (end-to-end) and between two adjacent ports (buffer-to-buffer), each communicating port is allocated a credit during the initialization procedure. 0 The transmitting port limits the number of outstanding unacknowledged frames to the allocated credit of each type and adjusts the credit according to the responses received. 0 The Credit_Count represents the number of outstanding data frames that have been NOT acknowledged and is not permitted to exceed the corresponding maximum credit negotiated at login.

30 6/22/ :39 Chapter 9Fiber Channel30 Flow Control Mechanism in Fibre Channel

31 6/22/ :39 Chapter 9Fiber Channel31 Frame Delimiters in Fibre Channel