1. Chapter Three
Network
Protocols

2. Objectives
Identify characteristics of TCP/IP, IPX/SPX, NetBIOS, and AppleTalk
Understand position of network protocols in OSI Model
Identify core protocols of each protocol suite and its functions
Understand each protocol’s addressing scheme
Install protocols on Windows 98 and Windows 2000 clients

3. Introduction to Protocols
Rules network uses to transfer data
Protocols that can span more than one LAN segment are routable
Multiprotocol network
Network using more than one protocol

4. TCP/IP Transmission Control Protocol/Internet Protocol (TCP/IP)
OSI Model
TCP/IP
Transmission Control Protocol/Internet Protocol (TCP/IP)
Suite of small, specialized protocols called subprotocols
Figure 3-1: TCP/IP compared to the OSI Model

5. TCP/IP Compared to the OSI Model
Application layer roughly corresponds to Session, Application, and Presentation layers of OSI Model
Transport layer roughly corresponds to Transport layers of OSI Model
Internet layer is equivalent to Network layer of OSI Model
Network Interface layer roughly corresponds to Data Link and Physical layers of OSI Model

6. The TCP/IP Core Protocols
Certain subprotocols of TCP/IP suite
Operate in Transport or Network layers of OSI Model
Provide basic services to protocols in other layers of TCP/IP
TCP and IP are most significant core protocols in TCP/IP suite

7. Internet Protocol (IP)
Provides information about how and where data should be delivered
Subprotocol that enables TCP/IP to internetwork
To internetwork is to traverse more than one LAN segment and more than one type of network through a router
In an internetwork, the individual networks that are joined together are called subnetworks

8. Internet Protocol (IP)
IP datagram
IP portion of TCP/IP frame that acts as an envelope for data
Contains information necessary for routers to transfer data between subnets
Figure 3-2: Components of an IP datagram

9. Internet Protocol (IP)
IP is an unreliable, connectionless protocol, which means it does not guarantee delivery of data
Connectionless
Allows protocol to service a request without requesting verified session and without guaranteeing delivery of data

10. Transport Control Protocol (TCP)
Provides reliable data delivery services
Connection-oriented subprotocol
Requires establishment of connection between communicating nodes before protocol will transmit data
TCP segment
Holds TCP data fields
Becomes encapsulated by IP datagram

11. Transport Control Protocol (TCP)
Address on host where application makes itself available to incoming data
Figure 3-3: A TCP segment

12. Additional Core Protocols of the TCP/IP Suite
User Datagram Protocol (UDP)
Connectionless transport service
Internet Control Message Protocol (ICMP)
Notifies sender of an error in transmission process and that packets were not delivered
Address Resolution Protocol (ARP)
Obtains MAC address of host or node
Creates local database mapping MAC address to host’s IP address

13. TCP/IP Application Layer Protocols
Telnet
Used to log on to remote hosts using TCP/IP protocol suite
File Transfer Protocol (FTP)
Used to send and receive files via TCP/IP
Simple Mail Transfer Protocol (SMTP)
Responsible for moving messages from one server to another, using the Internet and other TCP/IP-based networks
Simple Network Management Protocol (SNMP)
Manages devices on a TCP/IP network

14. Addressing in TCP/IP IP Address
Logical address used in TCP/IP networking
Unique 32-bit number
Divided into four groups of octets (8-bit bytes) that are separated by periods
IP addresses are assigned and used according to very specific parameters

15. Addressing in TCP/IP
Table 3-1: Commonly used TCP/IP classes
Though 8 bits have 256 possible combinations, only the numbers 1 through 254 are used to identify networks and hosts
Numbers 0 and 255 are reserved for broadcasts
Broadcast are transmissions to all stations on a network

16. Addressing in TCP/IP Loopback address
IP address reserved for communicating from a node to itself
Value of the loopback address is always
Internet Corporation for Assigned Names and Numbers (ICANN)
Non-profit organization currently designated by U.S. government to maintain and assign IP addresses

17. Addressing in TCP/IP Firewall Host
Specialized device (typically a router)
Selectively filters or blocks traffic between networks
May be strictly hardware-based or may involve a combination of hardware and software
Host
Computer connected to a network using the TCP/IP protocol

18. Addressing in TCP/IP
In IP address , to convert the first octet (131) to a binary number:
On Windows 2000, click Start, point to Programs, point to Accessories, then click Calculator
Click View, then click Scientific (make sure Dec option button is selected)
Type 131, then click Bin option button
The binary equivalent of number 131, , appears in the display window

19. Addressing in TCP/IP Static IP address
IP address manually assigned to a device
Dynamic Host Configuration Protocol (DHCP)
Application layer protocol
Manages dynamic distribution of IP addresses on a network

20. Viewing Current IP Information
Figure 3-4: Example of an IP configuration window

21. Viewing Current IP Information
Figure 3-5: IP address information on a Windows 2000 workstation

22. Addresses and Names
In addition to using IP addresses, TCP/IP networks use names for networks and hosts
Each host requires a host name
Each network requires a network name, also called a domain name
Together, host name and domain name constitute the fully qualified domain name (FQDN)

23. Figure 3-6: IPX/SPX compared to the OSI Model
Internetwork Packet Exchange/Sequenced Packet Exchange (IPX/SPX)
Protocol originally developed by Xerox
Modified and adopted by Novell in the 1980s for the NetWare network operating system
Figure 3-6: IPX/SPX compared to the OSI Model

24. IPX/SPX Core Protocols
Internetwork Packet Exchange (IPX)
Operates at Network layer of OSI Model
Provides routing and internetworking services
Similar to IP in TCP/IP suite
Figure 3-7: Components of an IPX datagram

25. IPX/SPX Core Protocols
Sequenced Packet Exchange (SPX)
Belongs to Transport layer of OSI Model
Works in tandem with IPX to ensure data are received:
Whole
In sequence
Error free

26. IPX/SPX Core Protocols
Figure 3-8: SPX packet encapsulated by an IPX datagram

27. IPX/SPX Core Protocols
Service Advertising Protocol (SAP)
Works in Application, Presentation, Session, and Transport layers of OSI Model
Runs directly over IPX
Used by NetWare servers and routers to advertise to entire network which services they can provide

28. IPX/SPX Core Protocols
NetWare Core Protocol (NCP)
Works within Presentation and Sessions layers of OSI Model
Works over IPX
Handles requests for services between clients and servers

29. Addressing in SPX/IPX IPX address
Address assigned to a device on an IPX/SPX network
Contains two parts:
Network address (external network number)
Node address

30. NetBIOS and NetBEUI Network Basic Input Output System (NetBIOS)
Originally designed by IBM to provide Transport and Session layer services
Adopted by Microsoft as its foundation protocol
Microsoft added Application layer component called NetBEUI

31. NetBIOS and NetBEUI NetBIOS Enhanced User Interface
Fast and efficient protocol
Consumes few network resources
Provides excellent error correction
Requires little configuration
Can handle only 254 connections
Does not allow for good security

32. NetBIOS and NetBEUI Compared to the OSI Model
Figure 3-9: NetBIOS/NetBEUI compared to the OSI Model

33. Figure 3-10: Identification tab in Network properties
NetBIOS Addressing
Figure 3-10: Identification tab in Network properties

34. AppleTalk Protocol suite used to interconnect Macintosh computers
Originally designed to support peer-to-peer networking among Macintoshes
Can now be routed between network segments and integrated with NetWare- and Microsoft-based networks
AppleTalk networks are separated into logical groups of computers called AppleTalk zones

35. AppleTalk and OSI Model
Figure 3-11: AppleTalk protocol compared to OSI Model

36. AppleTalk Subprotocols
AppleShare
AppleTalk Filing Protocol (AFP)
AppleTalk Session Protocol (ASP)
AppleTalk Transaction Protocol (ATP)

37. AppleTalk Subprotocols
Name Binding Protocol (NBP)
Routing Table Maintenance Protocol (RTMP)
Zone Information Protocol (ZIP)
Datagram Delivery Protocol (DDP)

38. Addressing in AppleTalk
AppleTalk node ID
Unique 8-bit or 16-bit number identifying a computer on an AppleTalk network
AppleTalk network number
Unique 16-bit number identifying the network to which a node is connected

39. Installing Protocols
After installing protocols, they must be binded to NICs and services they run on or with
Binding
Process of assigning one network component to work with another

40. Chapter Summary
Protocols define standards for communication between nodes on a network
Protocols vary in speed, transmission efficiency, utilization of resources, ease of setup, compatibility, and ability to travel between one LAN segments
TCP/IP is becoming most popular network protocol

41. Chapter Summary
TCP/IP suite of protocols can be divided into four layers roughly corresponding to seven layers of OSI Model
Operating in Transport or Network layers of OSI Model, TCP/IP core protocols provide communications between hosts on a network
Each IP address is a unique 32-bit number, divided into four groups of octets separated by periods

42. Chapter Summary Every host on a network must have a unique number
Internetworking Packet Exchange/Sequenced Packet Exchange (IPX/SPX) is a protocol originally developed by Xerox then modified and adopted by Novell in the 1980s for its NetWare network operating system
Core protocols of IPX/SPX provide services at Transport and Network layers of OSI Model

43. Chapter Summary
Addresses on an IPX/SPX network are called IPX addresses
Network Basic Input Output System (NetBIOS) was originally developed by IBM to provide Transport and Session layer services
Microsoft adopted NetBIOS as its foundation protocol, then added an Application layer component called NetBIOS Enhanced User Interface (NetBEUI)

44. Chapter Summary
To transmit data between network nodes, NetBIOS needs to know how to reach each workstation
Each workstation must have a NetBIOS name
AppleTalk is the the protocol suite used to interconnect Macintosh computers
An AppleTalk network is separated into logical groups of computers called AppleTalk zones

45. Chapter Summary
Though Apple has improved AppleTalk’s ability to use different network models and span network segments, it remains unsuited to large LANs or WANs
In addition to zone names, AppleTalk uses node IDs and network numbers to identify computers on a network
Though some protocols (such as NetBIOS) require no configuration after installation, others (such as TCP/IP) do require configuration