lan protocols chapter 5. learning objectives explain the following lan protocols and how they work...
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LAN Protocols
Chapter 5
Learning ObjectivesExplain the following LAN protocols and how they work with network operating systems: IPX/SPX, NetBEUI, AppleTalk, TCP/IP, SNA, DLC, DNA
Discuss and implement techniques to improve LAN performance
How LAN Protocols Work with Network Operating SystemsGive meaning to simple electrical signal that are carried on network communications cables
Can be transported individually or in combinations of two, three, or more
Multiple LAN ProtocolsAdvantage
Network can perform many different functions on same LAN
DisadvantageSome protocols operate in broadcast mode, causing a significant amount of redundant network traffic
Properties of a LAN ProtocolReliable network links
Relatively high speeds
Source and destination node address handling
Adherence to network standards (particularly IEEE 802)
LAN Protocols and Network Operating Systems
IPX/SPX and Novell NetWareIPX (Internetwork Packet Exchange)
Use with NetWare file server operating system
Routable, but chatty
SPX (Sequenced Packet Exchange)Enables exchange of application-specific data with greater reliability than IPX
Often used for exchange of database data
Deployment of IPX/SPXDOS-based computers
DOS shell drivers created by NetWare
Windows-based computersNovell Client32
Open Datalink Interface (ODI)
Network Driver Interface Specification (NDIS)
Microsoft’s NetWare Link (NWLink)
NDIS Network Architecture
IPX/SPX and Novell NetWareEmulation of IPX/SPX
Binding via NDIS
Other Protocols Used with NetWare
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Other Protocols Used with NetWare
NetBEUI and Microsoft Windows Servers
NetBEUI (NetBIOS Extended User Interface)
Developed by IBM in mid-1980sIncorporates NetBIOS for communications across a networkNative protocol for Windows NT ServerNot routable; most suited for small LANs using older Microsoft or IBM operating systemsCorresponds with several layers of OSI model
Why NetBEUI Works Well on Microsoft Networks
Simple to install
Handles large number of communication sessions on one network
Low memory requirements; can be quickly transported over small networks
Solid error detection and recovery
Disadvantages of NetBEUIInability to route medium-sized and large networks; not enough information in NetBEUI frame to identify specific networks
Few network analysis tools
AppleTalk and Mac OSAppleTalk
Peer-to-peer protocol used on networks for communications between Macintosh computers
Connectivity supported by Windows NT, Windows 2000, Windows .NET, and NetWare Server
AppleTalk Peer-to-Peer Networking
Comparison of AppleTalk Phase I and Phase II
Phase 1 Phase IINo internetworking; allows only one zone
Permits internetworking; up to 255 zones
Maximum number of stations: 254
Maximum number of stations: several million
Addressing accomplished by providing a node ID
Addressing uses combination of node ID and network identification
Functions only on a network in which it is the sole protocol
Can work on a network that uses multiple protocols
Services of AppleTalkRemote access to network files via AppleShare File Server Application
Printing services through AppleShare Print Server application
File services to DOS- and Windows-based systems via AppleShare PC application
Protocols Associated with AppleTalk
AARP
ADSP
AFP
ASP
ATP
DDP
ELAP
LLAP
NBP
PAP
RTMP
TLAP
ZIP
TCP/IP and Multiple Server Systems
TCP/IP (Transmission Control Protocol/ Internet Protocol)
Most widely used protocol
Offers a suite of protocols
Protocol of the Internet
Supported by most network server and workstation operating systems
Advantages of TCP/IPInternational language of network communicationsDesigned for use with wide range of network devicesMain protocol of most computer operating systemsMany troubleshooting and network analysis toolsUnderstood by a large body of network professionals
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Protocols and Applications of the TCP/IP Suite
SNA and IBM Operating Systems
SNA (Systems Network Architecture)Layered communications protocol used by IBM for communications between IBM mainframes and devices
Uses token ring as the access method
Advantages and Disadvantages of SNA
AdvantagesAvailable for over 25 years
Provide reliable and tested communications with IBM systems
DisadvantageProprietary; requires special devices and complex training to configure, manage, and troubleshoot
Physical Units on an SNA Network
Protocols and Applications That Work Through SNA
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DLC for Accessing IBM Operating Systems
DLC (Data Link Control) protocolEmulates SNA on Microsoft Windows operating systems
Not routable
Not truly designed for peer-to-peer communications between workstations, but only for connectivity to older IBM mainframe
DNA for Digital (Compaq) Computer Operating Systems
DNA (Digital Network Architecture)Developed for use on networks using DEC computers
AdvantageClosely follows OSI Reference model
DisadvantagesProprietary implementation
No longer widely used
Improving LAN PerformanceMinimize number of LAN protocols that must cross each router
Decreases the work routers must perform
Enables routers to process traffic faster
Does not create unnecessary traffic on network
Which Protocol?Do packets need to be routed?Size of network?Types of servers in use and the protocols they use?Are there mainframe host computers; what protocols do they use?Direct access to Internet or Web-based intranet applications?Speeds needed for WAN connections?Mission-critical applications?
Improving LAN PerformanceConnectivity issues
Eliminate unnecessary protocols configured on workstations
Chapter SummaryCommonly used LAN protocols and the network operating systems with which they are usedAdvantages and disadvantages of LAN protocolsImproving LAN performance by using only the protocols necessary in a particular situation