IP Networking. Overview. Networks Impact Daily Life. IP Networking - Part 1. How Networks Impact Daily Life. How Networks Impact Daily Life

Transcription

1 Overview Dipl.-Ing. Peter Schrotter Institute of Communication Networks and Satellite Communications Graz University of Technology, Austria Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planning and Cabling Networks Configuring and Testing the Network - Part 1 Networks Impact Daily Life Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planning and Cabling Networks Configuring and Testing the Network Instantaneous communication supports and improves our lives. How Networks Impact Daily Life How Networks Impact Daily Life Popular communication media such as IM, Wikis, Blogs, Podcasting, and Collaboration Tools Instant messaging Real time communication between 2 or more people based on typed text Weblogs (Blogs) Web pages created by an individual Podcasting Website that contains audio files available for downloading Information networks can be used in different ways of sharing and collaborating Improvement for teaching and learning ERASMUS IP Summer Course 2009: WiCoNet Page 1

2 How Networks Impact Daily Life How Networks Impact Daily Life Communication over a network changes the way we work Communication over a network supports the way we play Data Networking: Role, Components, and Challenges Data Networking: Role, Components, and Challenges Basic characteristics of communication Rules or agreements are 1 st established Important information may need to be repeated Various modes of communication may impact the effectiveness of getting the message across. Various elements make up a network Devices These are used to communicate w ith one another Medium This is how the devices are connected together Messages Rules Information that travels over the medium Governs how messages flow across netw ork Data Networking: Role, Components, and Challenges Network Architecture Characteristics Converged networks in communications A type of network that can carry voice, video & data over the same network Characteristics that are addressed by network architecture design Fault tolerance Scalability Quality of service Security ERASMUS IP Summer Course 2009: WiCoNet Page 2

3 Network Architecture Characteristics Network Architecture Characteristics Packet switching helps to improve the resiliency and fault tolerance of the Internet architecture Characteristics of the Internet Easy scaling to meet user demand Hierarchical Common standards Common protocols Network Architecture Characteristics Network Architecture Characteristics Need for Quality of Service Mechanisms to ensure it QoS mechanisms ensure quality of service for applications that require it Network Architecture Characteristics Network Architecture Characteristics For each type of traffic the appropriate QoS strategy has to be chosen Some networks must be secure ERASMUS IP Summer Course 2009: WiCoNet Page 3

4 Network Architecture Characteristics - Part 2 Basic measures to secure data networks Ensure confidentiality through use of User authentication Data encryption Maintain communication integrity through use of Digital signatures Ensure availability through use of Firewalls Redundant network architecture Hardware without a single point of failure Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planning and Cabling Networks Configuring and Testing the Network Network Structure Network Structure 3 common elements of communication message source the channel message destination Data is sent across a network in small chunks called segments Network definition data or information networks capable of carrying many different types of communications Network Structure Network Structure Definition of the components of a network Hardware Software End devices are the interface between human network and communications network Role of end devices: client server both client and server ERASMUS IP Summer Course 2009: WiCoNet Page 4

5 Network Structure Network Structure Role of an intermediary device in a data network is different to the role of an end device Role of an intermediary device provides connectivity and ensures data flows across network Network media and criteria for making a network media choice Network media is the channel over which a message travels Network Types Network Types Local Area Networks (LANs) A network serving a home, building or campus is considered a Local Area Network (LAN) Wide Area Networks (WANs) LANs separated by geographic distance are connected by a network known as a Wide Area Network (WAN) Metropolitan Area Networks (MANs) Interconnection of urban LANs, distances betw. LANs & MANs Network Types Network Types Internet The internet is defined as a global mesh of interconnected networks Network representations ERASMUS IP Summer Course 2009: WiCoNet Page 5

6 Function of Protocol in Network Communication Function of Protocol in Network Communication The importance of protocols and how they are used to facilitate communication over data networks A protocol is a set of predetermined rules Network protocols are used to allow devices to communicate successfully Function of Protocol in Network Communication Function of Protocol in Network Communication Protocol suites and industry standards Interaction of different protocols A standard is a process or protocol that has been endorsed by the networking industry and ratified by a standards organization Function of Protocol in Network Communication Layers with TCP/IP and OSI Model Technology independent Protocols Many diverse types of devices can communicate using the same sets of protocols This is because protocols specify network functionality, not the underlying technology to support this functionality Benefits of using a layered model include assists in protocol design fosters competition changes in one layer do not affect other layers provides a common language ERASMUS IP Summer Course 2009: WiCoNet Page 6

7 Layers with TCP/IP and OSI Model Layers with TCP/IP and OSI Model Describe TCP/IP Mode The Communication Process Layers with TCP/IP and OSI Model Layers with TCP/IP and OSI Model Protocol Data Units (PDU) and Encapsulation Process of sending and receiving messages Layers with TCP/IP and OSI Model Layers with TCP/IP and OSI Model Protocol and reference models A protocol model provides a model that closely matches the structure of a particular protocol suite Open Systems Interconnection Model (OSI) of ISO A reference model provides a common reference for maintaining consistency within all types of network protocols and services ERASMUS IP Summer Course 2009: WiCoNet Page 7

8 Layers with TCP/IP and OSI Model Addressing and Naming Schemes Comparison of OSI and TCP/IP model Labels in encapsulation headers are used to manage communication in data networks Addressing and Naming Schemes Addressing and Naming Schemes Examples for addressing in different layers: Layer 2: Ethernet MAC Addresses Layer 3: IP Addresses Layer 4: TCP/UDP Port numbers Labels in encapsulation headers are used to manage communication in data networks Addressing and Naming Schemes - Part 3 Information in the encapsulation header is used to identify the source and destination processes for data communication Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planning and Cabling Networks Configuring and Testing the Network ERASMUS IP Summer Course 2009: WiCoNet Page 8

9 Applications The Interface between Human and Data Networks Applications provide the means for generating and receiving data that can be transported on the network Applications The Interface between Human and Data Networks Applications, services and protocols work together in converting communication to data that can be transferred across the data network Applications The Interface between Human and Data Networks Applications, services and protocols play different roles in transporting data through networks Applications The Interface between Human and Data Networks Networking Protocols are able to identify several message properties that can be defined by a protocol The Role of Protocols in Supporting Communication Client and server processes have different tasks in data networks The Role of Protocols in Supporting Communication Examples of Application Layers services and protocols ERASMUS IP Summer Course 2009: WiCoNet Page 9

10 The Role of Protocols in Supporting Communication Different behaviors of client server networking compared with peerto-peer networking and peer-to-peer applications Features, Operation, and Use of TCP/IP Application Layer Services DNS protocol Support of DNS services Features, Operation, and Use of TCP/IP Application Layer Services HTTP protocol Supports delivery of w eb pages to the client Features, Operation, and Use of TCP/IP Application Layer Services POP and SMTP protocols Support of services Features, Operation, and Use of TCP/IP Application Layer Services Telnet protocol used for examining and managing netw orks Features, Operation, and Use of TCP/IP Application Layer Services SMB protocol File sharing in Microsoft-based netw orks ERASMUS IP Summer Course 2009: WiCoNet Page 10

11 Features, Operation, and Use of TCP/IP Application Layer Services - Part 4 Gnutella protocol supporting P2P services Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planning and Cabling Networks Configuring and Testing the Network Transport Layer Role and Services Transport Layer Role and Services Transport layer Major functions of the transport layer and the role it plays in data networks Transport Layer Role and Services Transport Layer Role and Services Supporting Reliable Communication Basic characteristics of the UDP and TCP protocols ERASMUS IP Summer Course 2009: WiCoNet Page 11

12 Transport Layer Role and Services Transport Layer Role and Services Representation of port number Description of port numbers in the TCP and UDP protocols The role of segments in the transport layer two principle ways segments can be marked for reassembly Application and Operation of TCP Mechanisms Application and Operation of TCP Mechanisms TCP reliability mechanism working as part of a session Port numbers Establishment of TCP sessions and directing segments to server process Application and Operation of TCP Mechanisms Application and Operation of TCP Mechanisms Handshaking during establishment of TCP sessions Handshake in the termination of TCP sessions ERASMUS IP Summer Course 2009: WiCoNet Page 12

13 Managing TCP Sessions Managing TCP Sessions TCP sequence numbers are used to reconstruct the data stream with segments placed in the correct order Usage of TCP sequence and acknowledgement numbers for management of exchanges in a conversation Managing TCP Sessions Managing TCP Sessions Retransmission remedy for lost data employed by TCP Mechanisms in TCP are managing the interrelationship between window size, data loss and congestion during a session UDP Protocol UDP Protocol Characteristics of the UDP protocol types of communication for which it is best suited The process specified by the UDP protocol to reassemble PDUs at the destination device ERASMUS IP Summer Course 2009: WiCoNet Page 13

14 UDP Protocol UDP Protocol Servers are using port numbers to identify a specified application layer process directing segments to the proper service or application UDP protocol and port numbers are utilized in clientserver communication. - Part 5 Network Layer Protocols and Internet Protocol (IP) Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planning and Cabling Networks Configuring and Testing the Network Tasks of the Network Layer in data networks Network Layer Protocols and Internet Protocol (IP) Network Layer Protocols and Internet Protocol (IP) Basic characteristics and the role of the IPv4 protocol Implications for using the IP protocol: connectionless ERASMUS IP Summer Course 2009: WiCoNet Page 14

15 Network Layer Protocols and Internet Protocol (IP) Network Layer Protocols and Internet Protocol (IP) Implications for using the IP protocol: unreliable delivery Implications for using the IP protocol: media independence Network Layer Protocols and Internet Protocol (IP) Network Layer Protocols and Internet Protocol (IP) Framing in the Transport Layer segments are encapsulated as packets Major header fields in the IPv4 protocol Role of each field in transporting packets Grouping Devices into Networks and Hierarchical Addressing Grouping Devices into Networks and Hierarchical Addressing There can be different reasons for grouping devices into sub-networks Dividing a large network can increase network performance ERASMUS IP Summer Course 2009: WiCoNet Page 15

16 Grouping Devices into Networks and Hierarchical Addressing Grouping Devices into Networks and Hierarchical Addressing Dividing a large network can increase network security Communication problems can emerge when very large numbers of devices are included in one large network Grouping Devices into Networks and Hierarchical Addressing Grouping Devices into Networks and Hierarchical Addressing Hierarchical addressing solves the problem of devices communicating across networks of networks Further subdividing networks into smaller networks Fundamentals of Routes, Next Hop Addresses and Packet Forwarding Fundamentals of Routes, Next Hop Addresses and Packet Forwarding Intermediary gateway device allowing devices to communicate across sub-divided networks IP packets are traversing unchanged via routers from sub network to sub-network ERASMUS IP Summer Course 2009: WiCoNet Page 16

17 Fundamentals of Routes, Next Hop Addresses and Packet Forwarding Fundamentals of Routes, Next Hop Addresses and Packet Forwarding Gateway are using a simple route table in directing packets toward their ultimate destinations Definition of a route and its three key parts Fundamentals of Routes, Next Hop Addresses and Packet Forwarding Fundamentals of Routes, Next Hop Addresses and Packet Forwarding The purpose and use of the destination network in a route The purpose and use of the next hop in a route Fundamentals of Routes, Next Hop Addresses and Packet Forwarding Fundamentals of Routes, Next Hop Addresses and Packet Forwarding Example: several IP packets are routed through several gateways from devices on one sub network to devices on other sub networks Routing protocols needed for both static and dynamic routes ERASMUS IP Summer Course 2009: WiCoNet Page 17

18 Fundamentals of Routes, Next Hop Addresses and Packet Forwarding Fundamentals of Routes, Next Hop Addresses and Packet Forwarding Routes can be manually configured to build routing table Routing protocols allow automatic learning of routes Continuous update of the routing table updated routes new networks (hosts) new (redundant) routes for already known networks (hosts) routes to be deleted Examples for routing protocols RIP (Routing Information Protocol) IGRP and EIGRP (CISCO proprietary) OSPF (Open Shortest Path First) BGP (Border Gateway Protocol) IS-IS (Intermediate System - Intermediate System) - Part 6 IP Addressing Structure Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planing and Cabling Networks Configuring and Testing the Network Dotted decimal structure of a binary IP address 8-bit binary in network addressing and Convertion to decimal IP Addressing Structure IP Addressing Structure Converting 8-bit binary to decimal Converting decimal to 8-bit binary ERASMUS IP Summer Course 2009: WiCoNet Page 18

19 Classification of IPv4 Addresses Types of Communication in the Network Layer 3 types of addresses in the network Characteristics of the 3 types of communication Reserved IPv4 Address Ranges Public and Private Addresses Historic IPv4 Address Assignment Assigning Addresses to Hosts End user devices can obtain addresses either statically through an administrator or dynamically through DHCP ERASMUS IP Summer Course 2009: WiCoNet Page 19

20 Assigning Addresses to Special Devices Assignment of Public IPv4 Addresses Regional agencies manage IP address registries via ISPs ISPs are further providing Internet connectivity IPv6 Addresses Subnetting (IPv4) Need for migration from IPv4 to IPv6 Testing the Network Layer with PING command Testing the Network Layer with TRACEROUTE Ping command is checking operability of IP protocol on a local host: ping between a local host and a gateway across a LAN between a local host and a gateway to a device in remote network Observation of the path between two talking devices ERASMUS IP Summer Course 2009: WiCoNet Page 20

21 - Part 7 Data Link Layer Services Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planing and Cabling Networks Configuring and Testing the Network Preparing communication for transmission on specific media Data Link Layer Protocols Control of Media Access Data Link Layer Framing Preparing a packet for transmission on a given media Hardware and Software Layers Protocols and Standards used ERASMUS IP Summer Course 2009: WiCoNet Page 21

22 Media Access Control (MAC) Techniques for Shared Media Media Access Control (MAC) Techniques for Non-shared Media Necessary to avoid collisions added overhead should be minimized Two media access control methods for shared media controlled access vs. contention-based access Full Duplex and Half Duplex Logical Topology MAC Addressing and Framing Packets are encapsulating into frames to facilitate the entry and exit of data on media MAC Addressing: Header and Trailer MAC Addressing not always needed Trailer is very important on "non-reliable" media ERASMUS IP Summer Course 2009: WiCoNet Page 22

23 - Part 8 Physical Layer Protocols & Services Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planing and Cabling Networks Configuring and Testing the Network Frames are represented by Bits Signals on Physical Layer during transport across the local media Physical Layer Standardization Physical Layer Signaling and Encoding ERASMUS IP Summer Course 2009: WiCoNet Page 23

24 Physical Layer Encoding Bandwidth, Throughput, and Goodput Transmission of bits, treating a collection of bits as a code Characteristics of Ethernet Media Impact of Interference Proper cabling reduces interference Characteristics of Network Media Wireless Network Media Basic characteristics of UTP cable Security in wireless communications ERASMUS IP Summer Course 2009: WiCoNet Page 24

25 - Part 9 Characteristics of Ethernet Network Media Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planing and Cabling Networks Configuring and Testing the Network The evolution of Ethernet: Topology and Standardization (IEEE 802.3) Hub / Repeater: electrical Signal Regeneration increased Distances Introduction of LAN Switches State-of-the-art Ethernet Key innovation for managing collisions on Ethernetbased networks Bridge / Switch: Point-to-Point links Reduction of the network load Deletion of corrupted frames Fiber optical and Twisted Pair cabling point-to-point topography large distances bandwidths up to 10 Gbit/s Standards and Implementation Characteristics of Ethernet in first 2 OSI Layers ERASMUS IP Summer Course 2009: WiCoNet Page 25

26 Media Access Control (MAC) and Logic Link Control (LLC) Sublayer Physical Implementations Logic Link Control Sublayer Media Access Control Method Ethernet Timing Function of MAC in Ethernet Layer 2 Addressing Layer 2 Addressing The Frame Encapsulating the Packet Comparing Layer 2 and Layer 3 Addressing ERASMUS IP Summer Course 2009: WiCoNet Page 26

27 Layer 2 Addressing Legacy Ethernet using Hubs Ethernet Unicast, Multicast and Broadcast Ethernet using Switches Address Resolution Protocol (ARP) Mapping IP to MAC Addresses Address Resolution Protocol (ARP) - Part 10 ARP process ARP entry enables a frame to be sent Destinations Outside the Local Network Removing Address Mappings Broadcast issues (overhead / flood on the media) Security issues (spoofing) Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planing and Cabling Networks Configuring and Testing the Network ERASMUS IP Summer Course 2009: WiCoNet Page 27

28 Requirements for LAN Planning Switches and Redundancy Selection of the appropriate hardware and LAN cabling Key aspects for devices cost ports speed expandable / modular managable type of cabling horizontal, backbone, patch cable for intermediate or end devices Pinout for Connectors Types of Connections in a LAN depending on straight-through or cross-over cabling WAN connections differ from LAN connections Device management connections Design an Addressing Scheme for an Inter-network Calculate the Address Ranges for Subnetworks Assign ranges for hosts, network devices and the router interface ERASMUS IP Summer Course 2009: WiCoNet Page 28

29 - Part 11 Internetwork Operating System (IOS) Fundamentals of Communicating over the Network Application Layer Functionality and Protocols OSI Transport Layer OSI Network Layer Addressing the Network (IPv4) OSI Data Link Layer OSI Physical Layer Ethernet Planing and Cabling Networks Configuring and Testing the Network wide usage for professional network devices providing Security Addressing Interfaces Routing QoS Managing Resources IOS Startup and Running Config IOS Mode Hierarchical Structure Identification of IOS Modes Basic IOS Command Structure Help, feedback and shortcuts are available in different IOS modes ERASMUS IP Summer Course 2009: WiCoNet Page 29

30 Variants of IOS Show command Command Line Interface (CLI) Accessing various IOS configuration modes using CLI Basic Device Configuration Restricted Access with Passwords Naming of devices is essential to avoid confusions Naming conventions Virtual Terminal Password Enable Password Enable Secret Password IOS Startup Config Router Interfaces Examine the startup config, make changes to config, and replace the startup config with the running config Multiple interfaces necessary (LAN, WAN) Assign interface descriptions ERASMUS IP Summer Course 2009: WiCoNet Page 30

31 Configuring Router Interfaces Host Addressing Parameters Master addressing scheme assigning IP parameters to a host Select, Apply, and Verify Appropriate Addressing Parameters to a Host Ipconfig Ping Show ip int Traceroute Verification of Connectivity Further Verification and Tests Ping command in the CLI to test: if IP protocol is operational if IP protocol is properly bound to a NIC if a host can actively communicate across the local network if the local host can communicate across the internetwork to a given remote host measure relative network performance by regularly checks Traceroute: step by step connectivity tests Address Resolution Protocol (ARP) verifying the knowledge of the physical addresses of the hosts End Thank you very much for your kind attention! Have an interesting ERASMUS IP Summer Course! ERASMUS IP Summer Course 2009: WiCoNet Page 31