Section 5.1 Explain why standards are necessary for networking Explain how an Ethernet network functions List Ethernet classifications Section 5.2 Explain how a token-passing network functions List wireless network classifications Explain how wireless transmissions are sent

Section 5.3 Section 5.4 Map TCP/IP protocols to the OSI model Define TCP and IP Explain IP addressing Section 5.4 Describe the AppleTalk protocols Explain the protocols NetBIOS and NetBEUI Demonstrate knowledge of the NetWare protocols

Common LAN Models Guide to Reading 5.1 Main Ideas pp. 136-141 Common LAN Models 5.1 Guide to Reading Main Ideas Manufacturers need standards so their devices can communicate with each other. The IEEE 802.x standards define what happens at the Physical and Data Link Layers. 802.3 standards are for Ethernet networks. Ethernet networks use a contentious means of accessing the network called CSMA/CD. Key Terms Logical Link Control (LLC) Ethernet contention frame device driver

Common LAN Models IEEE 802.x 5.1 pp. 136-141 Common LAN Models 5.1 IEEE 802.x In the 1970s, the Institute of Electrical and Electronics Engineers (IEEE) established Project 802. It defined network standards for the physical components of a network.

Common LAN Models IEEE 802.x 5.1 pp. 136-141 Common LAN Models 5.1 IEEE 802.x Project 802 standards fit into the OSI reference model with two differences: 802 is limited to the Physical and Data Link Layers of the OSI model. 802 divides the Data Link Layer into two sublayers Logical Link Control (LLC) Media Access Control (MAC) Logical Link Control (LLC) A sublayer of the Data Link Layer that is responsible for establishing and terminating links to other computers and sequencing and acknowledging frames and controlling frame traffic. (p. 136)

Common LAN Models IEEE 802.x 5.1 pp. 136-141 Common LAN Models 5.1 IEEE 802.x The IEEE 802 committee defines the specifications for LAN architectures, including: Ethernet Token bus Wireless personal area networks

Common LAN Models IEEE 802.3: Ethernet Standard 5.1 pp. 136-141 Common LAN Models 5.1 IEEE 802.3: Ethernet Standard Ethernet could be considered the parent of LAN technology. An earlier network, named ALOHA, was the first to use CSMA/CD as its means of controlling network access and contention. Ethernet A LAN architecture that uses a bus topology and relies on CSMA/CD to regulate traffic on the main communication line. It uses a bus topology and is based on the IEEE 802.3 standard. (p. 137) contention The competition among stations on a network for the opportunity to use a communication line or network resource. (p. 137)

Common LAN Models IEEE 802.3 5.1 Many LANs rely on CSMA/CD to: pp. 136-141 Common LAN Models 5.1 IEEE 802.3 Many LANs rely on CSMA/CD to: Gain access to the network when they have packets to transmit. Ensure that two nodes do not try to transmit at the same time. A collision occurs if two computers put data on the cable at the same time.

pp. 136-141 Common LAN Models 5.1 IEEE 802.3 One drawback of Ethernet networks is the limited number of nodes a network can support. The 5-4-3 rule was created to help maintain network efficiency. It specifies that there can be no more than 5 cable segments, 4 repeaters, and 3 populated segments that can exist in any collision domain.

pp. 136-141 Common LAN Models 5.1 IEEE 802.3 Ethernet networks vary in topology, speed, and cabling but have the following elements in common: Use CSMA/CD as the means of gaining access to the network. Are all defined in the IEEE 802.3 specifications. Rely on broadcast transmissions that deliver signals to all nodes at the same time. Are primarily baseband networks.

pp. 136-141 Common LAN Models 5.1 IEEE 802.3 Ethernet networks use a frame to transmit information. The frame ranges from 64 bytes to 1,518 bytes but are made of the same pieces. frame A format that Ethernet networks use for transmitting data packets. The frame contains the preamble, source and destination addresses, data, type of protocol used to send the frame, and the CRC. (p. 139)

Common LAN Models Drivers and the NIC 5.1 pp. 136-141 Common LAN Models 5.1 Drivers and the NIC Network devices use device drivers to allow hardware components to communicate to each other. NIC drivers provide a virtual communication channel between the computer and the NIC. device driver Software that helps a computer work with a particular device. (p. 140)

Common LAN Models You Try It 5.1 pp. 136-141 Common LAN Models 5.1 You Try It Activity 5A – Locating NIC Drivers (p. 140)

Other LAN Models Guide to Reading 5.2 Main Ideas pp. 142-147 Other LAN Models 5.2 Guide to Reading Main Ideas Token-passing networks take turns to gain access to the network. Token-passing networks can reliably determine when each computer will be able to transmit. Wireless networks rely on a type of contentious access known as CSMA/CA. Key Terms Attached Resource Computer Network (ARCnet) Token Ring Multistation Access Unit (MAU) Integrated Services LAN (ISLAN) Integrated Services Digital Network (ISDN) carrier sense multiple access with collision avoidance (CSMA/CA) Wi Fi

Other LAN Models Tokens and Token Passing 5.2 pp. 142-147 Other LAN Models 5.2 Tokens and Token Passing Token-passing networks work like a relay race, passing the token in a predetermined order through the network. Only the node that currently holds the token is allowed to transmit and it can only transmit a single packet.

Other LAN Models IEEE 802.4 and ARCNet 5.2 pp. 142-147 Other LAN Models 5.2 IEEE 802.4 and ARCNet ARCNet was established before the IEEE developed the specifications for networks. It is popular for smaller networks because it is flexible and easy to set up. Attached Resource Computer Network (ARCnet) A PC-based LAN architecture that corresponds to the IEEE 802.4 specification. An ARCnet is built using either a bus or a star topology. (p. 143)

Other LAN Models IEEE 802.5 and Token Ring 5.2 pp. 142-147 Other LAN Models 5.2 IEEE 802.5 and Token Ring Token Ring is an IBM architecture separate from the IEEE token ring. Token Ring relies on nodes that are connected to one of more hubs called multistation access units (MAU). Token Ring An IBM-designed architecture created to connect PC’s with IBM’s larger midrange and mainframe computers. (p. 144) Multistation Access Unit (MAU) The connection or hub that forms a logical ring. A Token Ring has a logical ring topology. (p. 144)

Other LAN Models IEEE 802.5 and Token Ring 5.2 A Token Ring network: pp. 142-147 Other LAN Models 5.2 IEEE 802.5 and Token Ring A Token Ring network: Typically transfers information at 1 Mbps or 4 Mbps per second (IEEE version) or at 4 Mbps or 16 Mbps (IBM version) Uses baseband transmission Is based on twisted-pair or fiber optic cable

Other LAN Models Other IEEE LAN Specifications 5.2 pp. 142-147 Other LAN Models 5.2 Other IEEE LAN Specifications Other wired IEEE 802 specifications include: Isochronous LAN Integrated Services LAN (ISLAN) Integrated Services Digital Network (ISDN) Integrated Services LAN (ISLAN) Isochronous LANs aimed at enabling multimedia capabilities on a network. (p. 145) Integrated Services Digital Network (ISDN) A technology that delivers different types of information—voice, data, video—in digital form over standard telephone cabling. (p. 145)

Other LAN Models Other IEEE LAN Specifications 5.2 pp. 142-147 Other LAN Models 5.2 Other IEEE LAN Specifications IEEE 802.11 set standards for wireless LAN communications. These networks are used where: Nodes must move around freely. Network connections are needed in a busy area. Connections are unreliable or dependent on external factors. It is difficult or impossible to wire the building.

Other LAN Models Other IEEE LAN Specifications 5.2 pp. 142-147 Other LAN Models 5.2 Other IEEE LAN Specifications Wireless networks use CSMA/CA to transmit data through the network. The three major variations of wireless networking, 802.11a, 802.11b, and 802.11g are commonly referred to as Wi Fi. carrier sense multiple access with collision avoidance (CSMA/CA) These nodes “listen” to the transmission medium for a chance to transmit. (p. 145) Wi Fi In wireless network technology, the three standards 802.11a, 802.11b, and 802.11g are commonly referred to as this. (p. 145)

Other LAN Models Other IEEE LAN Specifications 5.2 pp. 142-147 Other LAN Models 5.2 Other IEEE LAN Specifications At the Physical Layer, wireless LANs rely on two different methods of transmission: Diffused infrared light signal Radio signals

Other LAN Models Guide to Reading 5.3 Main Ideas pp. 149-153 Other LAN Models 5.3 Guide to Reading Main Ideas TCP establishes a connection between hosts in order to reliably transmit data. IP relies on a system of addresses to locate individual hosts on the network. IP packets can be routed from one network to another. Key Terms Transmission Control Protocol (TCP) Internet Protocol (IP) Domain Name System (DNS) User Datagram Protocol (UDP)

Other LAN Models Introduction to TCP/IP 5.3 pp. 149-153 Other LAN Models 5.3 Introduction to TCP/IP As more and more companies found it essential to “internetwork” with other networks, Transmission Control Protocol/Internet Protocol (TCP/IP) emerged as a standard. Transmission Control Protocol (TCP) A protocol that creates a connection between the sending and receiving computers, and then makes sure that all the data arrive safely. (p. 149) Internet Protocol (IP) A protocol responsible for routing packets, sometimes through many different networks. (p. 149)

Other LAN Models Introduction to TCP/IP 5.3 pp. 149-153 Other LAN Models 5.3 Introduction to TCP/IP Every time you use the Internet, you are working with numeric IP addresses. Your Web browser uses a Domain Name System (DNS) to connect the domain name to the 32-bit number of the IP address. Domain Name Server (DNS) Web browsers use this to locate the IP address of the domain name that the user entered in the address bar of the browser (p. 150)

Other LAN Models Introduction to TCP/IP 5.3 pp. 149-153 Other LAN Models 5.3 Introduction to TCP/IP Building on the TCP/IP stack are other protocols, including: File Transfer Protocol (FTP) Telnet Simple Mail Transfer Protocol (SMTP) Simple Network Management Protocol (SNMP) Hypertext Transfer Protocol (HTTP)

Other LAN Models TCP/IP and OSI 5.3 pp. 149-153 Other LAN Models 5.3 TCP/IP and OSI TCP/IP and the OSI do not exactly match up. But each of the TCP/IP layers correspond to one or more of the OSI layers.

Other LAN Models TCP/IP and OSI 5.3 pp. 149-153 Other LAN Models 5.3 TCP/IP and OSI The Transport Layer of the TCP/IP can use either TCP or User Datagram Protocol (UDP) depending on the requirements of the transmission. User Datagram Protocol (UDP) A connectionless transport protocol that is responsible for end-to-end transmission of data. It sends the data, but provides little in the way of error correction. (p. 151)

Other LAN Models Physical Address 5.3 pp. 149-153 Other LAN Models 5.3 Physical Address Every computer in the world is assigned a unique IP address. The address consists of two parts, a network address and an address that identifies the node or host. Depending on your network configuration, your IP address may be fixed, or assigned to your computer when you boot up.

Other LAN Models You Try It 5.3 pp. 149-153 Other LAN Models 5.3 You Try It Activity 5B – Finding Your IP Address and MAC Address Using Windows (p. 152) Activity 5C – Finding Your IP Address and MAC Address Using UNIX (p. 153)

Other Models and Protocols pp. 155-158 Other Models and Protocols 5.4 Guide to Reading Main Ideas Many protocol stacks provide services and communication on different types of networks. AppleTalk is used for Macintosh networks. Microsoft Windows-based computers use the NetBIOS interface. NetWare is hardware-independent network software that allows networks running on different architectures to be joined together. Key Terms AppleTalk Network Basic Input/ Output System (NetBIOS) NetBIOS Extended User Interface (NetBEUI) NetWare Internetwork Packet Exchange/Sequenced Packet Exchange (IPX/SPX)

Other Models and Protocols pp. 155-158 Other Models and Protocols 5.4 AppleTalk Apple Computer’s LAN hardware and software use a protocol stack called AppleTalk. AppleTalk corresponds to five of the seven layers of the OSI reference model. AppleTalk Transaction Protocol (ATP) A protocol in an AppleTalk network that transports packets. (p. 156)

Other Models and Protocols pp. 155-158 Other Models and Protocols 5.4 NetBIOS Most applications that run within Windows use NetBIOS. It has four primary functions. Name Recognition Datagram Service Session service NIC/session status Network Basic Input/Output System (NetBIOS) An interface that evolved into a standard method for applications to access protocols in the Transport Layer. (p. 156)

Other Models and Protocols pp. 155-158 Other Models and Protocols 5.4 NETBEUI Although NetBEUI is small and fast, it does not support routing. This restricts its usefulness to only a single segment of a LAN. NetBIOS Extended User Interface (NetBEUI) A protocol developed by IBM in the mid-1980s and was designed for LANs of up to 200 computers. (p. 157)

Other Models and Protocols pp. 155-158 Other Models and Protocols 5.4 NETBEUI NetBEUI was designed for small networks. On Microsoft Windows OS, it acts as a go-between for the lower and higher levels.

Other Models and Protocols pp. 155-158 Other Models and Protocols 5.4 Netware Protocols and IPX/SPX Novell Corporation introduced NetWare early in the development of networking. Internetwork Packet Exchange/Sequenced Packet Exchange (IPX/SPX) is a routable protocol developed by Novell that can be used for larger networks. NetWare A software networking product that runs on top of existing hardware, such as that used in the Ethernet and Token Ring networks. See also Novell Netware. (p. 158) Internetwork Packet Exchange/Sequenced Packet Exchange (IPX/SPX) A protocol stack that was designed by Novell for its NetWare networks. (p. 158)

Other Models and Protocols pp. 155-158 Other Models and Protocols 5.4 Netware Protocols and IPX/SPX Notice how some of the NetWare protocols operate at several OSI levels simultaneously.

Chapter 5 Resources For more resources on this chapter, go to the Introduction to Networks and Networking Web site at http://networking.glencoe.com.