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Chapter 3

Chapter 3: Planning Network Protocols and Compatibility

Learning Objectives Chapter 3

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Explain basic network concepts, including network terms, types of networks, and network cards Explain the NDIS and ODI network driver specifications Explain the communications protocols used in Windows 2000 Server, including TCP/IP, NWLink, NetBEUI, DLC, and AppleTalk

Learning Objectives (continued) Chapter 3

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Plan network binding order, change the binding order, and bind and unbind protocols Plan how to implement protocols on different types of networks

Protocol Chapter 3

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A protocol consists of guidelines for: ◆ How data

is formatted into discrete units called packets and frames ◆ How packets and frames are transmitted across one or more networks ◆ How packets and frames are interpreted at the receiving end

General Sections in Packets and Frames ■

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Header – contains routing information and controls how the packet is transmitted Data Trailer or footer – used mainly for error correction Used in much the same was as a postal address is used to mail a letter

Packet and Frame Format Chapter 3

Header with source, destination, and routing information

Variable-length data

Footer with error data

Figure 3-1 Basic packet and frame format

Wide Area Network Chapter 3

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Wide Area Network (WAN): A farreaching system of networks that can extend across state lines and across continents. WANs are usually connected by relatively slow speed communication links such as a T-1 or frame relay circuit.

Network Interface Card Communication Medium Options

Chapter 3

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Coaxial cable (thick and thinnet) Twisted-pair (shielded and unshielded) Fiber-optic Wireless (infrared, radio wave, microwave, satellite)

Ethernet and Token Ring Chapter 3

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Ethernet: A network transport system that uses a carrier sensing and collision detection method to regulate data transmissions Token ring: A network transport method that uses a token, which is passed from node to node, to coordinate data transmissions

NDIS Chapter 3

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Network Driver Interface Specification (NDIS): A set of standards developed by Microsoft and 3COM for network drivers that enables communication between a NIC and a protocol, and that enables the use of multiple protocols on the same network Using NDIS, any NIC adapter maker can write a driver that can communicate with any protocol stack program (such as TCP/IP).

NDIS Architecture Chapter 3

Network protocol (such as TCP/IP)

Windows 2000 with NDIS driver installed binding the protocol with the NIC

Network interface card

Figure 3-5 Binding a protocol to a NIC

ODI Chapter 3

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Open Datalink Interface (ODI): A driver interface that is used by Novell NetWare networks to transport multiple protocols on the same network

Microsoft-Supported Communication Protocols ■ ■ ■

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TCP/IP – universal, flexible, routable protocol NWLink – MS version of IPX/SPX protocol NetBEUI – Data transport protocol used on small MS based networks. DLC – IBM Mainframe, minicomputers, and printers AppleTalk NetBIOS – Not a protocol. Used as a method for interfacing software with network services. Also provides a naming convention on Windows networks.

TCP/IP Chapter 3

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Consists of two main components ◆ Transmission

Control Protocol (TCP) – Transports data and performs extensive error checking to ensure that data is delivered successfully ◆ Internet Protocol (IP) - rules for routing data between networks and ensuring that it reaches the correct destination address

TCP/IP Addressing Chapter 3

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Dotted Decimal Notation: Notation An addressing technique that uses four octets (134.22.101.125) Each server, workstation, or other network devices must have a unique IP address to communicate with other nodes. All dotted decimal notation is eventually converted to binary by the protocol stack: 100000110.00010110.01100101.01111101

Subnet Mask Chapter 3

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Subnet mask: used to indicate the class of addressing (A, B or C) used on a network and to divide a network into subnetworks as a way to control traffic and enforce security Class A – 255.0.0.0 Class B – 255.255.0.0 Class C – 255.255.255.0

Configuring the IP Address and Subnet Mask in Windows 2000

Figure 3-7 IP address and subnet mask setup

Chapter 3

Static and Dynamic Addressing Chapter 3

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Dynamic addressing: Involves automatically assigning an IP address to workstation or server, usually via a DHCP server. Static addressing: Involves manually assigning an IP address and subnet mask to a workstation or server.

TCP/IP Advantages Chapter 3

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Well-suited for medium and large networks Designed for routing between networks; has high degree of reliability and scalability Used worldwide for directly connecting to the Internet and by Web servers Used to connect to a wide variety of other computer systems such as IBM Mainframe and Unix. Compatible with Microsoft Windows Sockets

TCP/IP Disadvantages Chapter 3

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More difficult to set up and maintain than other protocols Somewhat slower than IPX/SPX and NetBEUI on networks with light to medium traffic

Routing via TCP/IP Chapter 3

E th e r n e t

E th e rn e t

F ra m e fo r w a r d e d to th e r ig h t n e tw o rk b y th e ro u te r

T r a n s m itte d fra m e T C P /IP - b a s e d in tr a n e t s e r v e r

R o u te r E th e r n e t

Figure 3-8 Router forwarding packets to a designated network

E th e rn e t

F ra m e re a c h e s th e d e s ig n a te d w o rk s ta tio n E th e rn e t

Protocols and Applications in the TCP/IP Suite ■

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TCP – A connection oriented protocol that is used with IP for reliable end-to-end communications UDP – Used as an alternative to TCP in situations where speed of delivery is more important than error checking IP – Handles all addressing and routing Telnet – application protocol that provides terminal emulation FTP – download files from remote hosts SMTP – transfer electronic mail messages

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Protocols and Applications in the TCP/IP Suite ■

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DNS – resolves host names to IP addresses on the internet or intranet. Windows 2000 offers dynamic DNS services. ARP – Resolves IP addresses to the physical (MAC) address of a destination host SNMP – Used to gather statistics on network performance and to locate network problems. IGMP – Multicasting ICMP – Network error reporting (ping and traceroute utilities)

Protocols and Applications in the TCP/IP Suite (continued) ■

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RIP – used by routers to share network information (route tables sent to every router every 30 seconds) OSPF – Similar to RIP, but more efficient. Uses multicasting to send updates to other routers. Only changes are sent, not the entire routing table. HTTP – transport for HTML documents

IPX/SPX and NWLink Chapter 3

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IPX: A connectionless protocol developed by Novell for use with its NetWare server operating system SPX: A connection-oriented protocol used on Novell networks when there is a particular need for reliable delivery NWLink - A network protocol that simulates the IPX/SPX protocol for Microsoft Windows communications with Novell NetWare file servers and compatible devices

Client Service for NetWare (CSNW) Components ■

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CSNW is used on Windows 2000 Server to enable communication with Novell Netware systems CSNW has three components: ◆ Client

Service for NetWare ◆ NWLink IPX/SPX ◆ NWLink NetBIOS

Chapter 3

CSNW Installed in Windows 2000

Chapter 3

Figure 3-9 Windows 2000 with CSNW components installed

Configuring NWLink Chapter 3

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Configure three elements: ◆ Frame

type ◆ Network number ◆ Internal network number

When to Use NWLink Chapter 3

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To enable a computer running Windows 2000 to access a NetWare IPX server To set up Windows 2000 as a gateway to a NetWare server To enable NetWare clients to access a Windows 2000 server

Planning Tip Chapter 3

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If your NetWare server is version 5.x or higher, convert from IPX/SPX to TCP/IP for better network communication options and better compatibility with Windows 2000 servers

NetBIOS and NetBEUI Chapter 3

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NetBIOS – Network Basic Input/Output System: A combination software interface and network naming convention (not a protocol) NetBEUI - NetBIOS Extended User Interface: A non-routable communications protocol native to early Microsoft network communications

When to Use NetBEUI Chapter 3

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For temporary backward compatibility when converting from Windows NT Server to Windows 2000 Server For small networks that do not have Internet access, that do not use the Active Directory, or require routing. For backward compatibility with particular applications

Binding Order Chapter 3

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Windows NT and Windows 2000 enable you to set a binding order which establishes the protocol that will be tried first in a network communication (or a communication with a network printer) You should put the most frequently used protocol or service first in your binding order.

Considerations in Selecting the Right Protocol(s) ■ ■ ■ ■

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Routing needs Size of the network in terms of connections Presence of Windows 2000 servers Presence of mainframes and other computers that use SNA Presence of NetWare servers Access to the Internet or intranets

Chapter Summary Chapter 3

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Protocols are the life blood of a network, thus plan their use carefully. The Microsoft NDIS driver enables using one or more protocols such as TCP/IP, IPX/SPX, NetBEUI, DLC, and AppleTalk. For modern networking TCP/IP implementations are preferred.

Chapter Summary Chapter 3

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Plan to use only the protocols necessary. Tune network binding order in Windows NT and Windows 2000 operating systems to enhance network performance.