NetworkProtocols

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

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

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

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

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

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 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 In an internetwork, the individual networks that are joined together are called subnetworks

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

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

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

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

TCP/IP Application Layer Protocols Telnet Used to log on to remote hosts using TCP/IP protocol suite 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 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 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 Manages devices on a TCP/IP network

Addressing in TCP/IP IP Address Logical address used in TCP/IP networking Logical address used in TCP/IP networking Unique 32-bit number 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 IP addresses are assigned and used according to very specific parameters

Addressing in TCP/IP 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 Broadcast are transmissions to all stations on a network Table 3-1: Commonly used TCP/IP classes

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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)

Chapter Summary To transmit data between network nodes, NetBIOS needs to know how to reach each workstation Each workstation must have a NetBIOS name 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