1. What is the Network ? Two or more connected computers that can Share resources such as : Data Printer Application

2. Network types ( LAN, MAN, WAN ) –Three main networking technologies are used to connect computers and networks together: Local area network (LAN) Metropolitan area network (MAN) Wide area network (WAN)

3. LAN Used to network computers located in a limited geographical area such as a room, floor, or building. Speed : 1Mbps, 100Mbps, 1Gbps, 10Gbps

4. MAN A MAN is used to interconnect networks that are larger than a LAN but smaller than a WAN.

5. EXAMPLE OF A MAN

6. WAN Spans a large geographic area Defined as an internetwork that connects many LANs using service provider. Examples of WANs –The Internet

7. EXAMPLE OF A WAN

8. Topologies Bus : physical Star : physical Ring : logical Mesh : physical

10. Cable 10BASE-T/ 100BASE-TX Straight-Through Pin Label 1234567812345678 TX+ TX- RX+ NC RX- NC 1234567812345678 TX+ TX- RX+ NC RX- NC Straight-Through Cable Wires on cable ends are in same order. UTP Implementation (Straight- Through)

11. Cable 10BASE-T or 100BASE-TX Straight-Through Crossover Cable Some wires on cable ends are crossed. Pin Label 1234567812345678 TX+ TX- RX+ NC RX- NC 1234567812345678 TX+ TX- RX+ NC RX- NC EIA/TIA T568AEIA/TIA T568B UTP Implementation (Crossover)

12. Repeater

13. A repeater is a device that regenerates and amplifies a signal, to counteract the effects of attenuation

14. HUB

15. is a device used to connect all of the computers on a star network. From the outside, a hub looks like nothing more than a box with a series of cable connectors and LEDs in it Two Types: Active and Passive Active :amplifies the signals and immediately transmits them through all of the other ports. Passive: transmits the signals through all of the other ports.

16. Bridges Operate at Layer 2 of the OSI model Forward, filter, or flood frames Few ports Slow

17. Layer 2 devices A layer 2 device is a device that understand MAC, for example: NIC (Network Interface Card) Bridge : - address learning - forwarding decisions are based on software - bridge is used for LAN segmentation - max. 16 port. Switch: - a multi-port bridge up to 567 port - forwarding decisions are based on hardware ASIC (faster than bridge)

18. functions of a switch - Address learning - Forward/filter decision - Loop avoidance ( Loop free )

19. –Redundant topology eliminates single points of failure. –Redundant topology causes broadcast storms, multiple frame copies, and MAC address table instability problems. Redundant Topology

20. Provides a loop-free (Loop Avoidance) redundant network topology by placing certain ports in the blocking state Spanning Tree Protocol Block

21. Router

22. functions of a router - connect between networks - Select best path - Divide broadcast domain - Packet forwarding

23. Identify Collision and Broadcast Domains Collision domain =3 and Broadcast Domains=3

24. Identifying Collision and Broadcast Domains Collision domain =8 and Broadcast Domains=5

25. Comparison Connectionless Connection-oriented Fast deliverySequencing Limited error checkingAcknowledgement Unreliable deliveryReliable delivery Session establishment Data recovery UDPTCP

26. Comparison ServersClients Any device that provides access to resources ((offer services Any device that requests services from a remote application

27. Static Routing –Uses a route that a network administrator enters into the router manually Dynamic Routing –Uses a route that a network routing protocol adjusts automatically for topology or traffic changes Identifying Static and Dynamic Routing

28. Comparison BRIPRI 2B+D 23B+D 128Kbps1.544Mbps PSTNT1 Lines

29. OSI 7 layer OSI Open System Interconnection We want the system to be standard to can any one use it ISO International Standard Organization Make standarization to main task for operation ( IEEE)

30. 30 OSI Model Overview Data Flow Layers Transport Layer Data Link Network Layer Physical Application (Upper) Layers Session Presentation Application

31. Layer 7 - The Application Layer It’s the S\w on our pcs that is used to represent a user interface to the network & so aids the user to make applications. 7 Application 6 Presentation 5 Session 4 Transport 3 Network 2 Data Link 1 Physical

32. 7- Application Layer HTTP : Browsing protocol FTP : File Transfer Protocol TFTP : Trivial FTP Telnet : Remote access protocol SMTP : Simple Mail Transfer protocol SNMP : Simple Network Management Protocol DNS : Domain Name System DHCP : Dynamic Host Configuration Protocol

33. Layer 6 - The Presentation Layer This layer is responsible for presenting the data in the proper format. - Compression & decompression of data Examples: AVI,JPG,…. 7 Application 6 Presentation 5 Session 4 Transport 3 Network 2 Data Link 1 Physical

34. Layer 5 - The Session Layer Give orders for: establishment, management, and termination of the session between different application. Specifies communication mode ( Half duplex – full duplex ) 7 Application 6 Presentation 5 Session 4 Transport 3 Network 2 Data Link 1 Physical

35. Layer 4 - The Transport Layer Responsible for actual mechanism of: 1.Establishment of connection. 2.Management of connection: 2.1) segmentation. 2.2) sequencing. 2.4) error detection &correction. 2.5) flow control. 3.Termination of connection. Examples: TCP (transmission control protocol). UDP (User Datagram Protocol). 7 Application 6 Presentation 5 Session 4 Transport 3 Network 2 Data Link 1 Physical

36. Flow control Pc1 Pc2 stop Go on Buffering Congestion avoidence

37. Layer 3 - The Network Layer Responsible for: 1.End-to-end delivery. 2.Logical addressing. EX: IPv4,IPv6,IPX,APPLETALK 3. Routing (choose the best path to destination.) 7 Application 6 Presentation 5 Session 4 Transport 3 Network 2 Data Link 1 Physical

38. Layer 2 - The Data Link Layer Responsible for: 1.Arbitration : find the best time to send the data ( CSMA/CD & taken) 2.Hop-to hop data delivery. 3.Hop-to-hop addressing (MAC Address in Ethernet). 4. error detection 4.1- parity check : but very week 4.2-CRC : Depend on mathematical equation 7 Application 6 Presentation 5 Session 4 Transport 3 Network 2 Data Link 1 Physical

39. Layer 2 - The Data Link Layer Data link sub-layers : LLC : (logical link control) places information in the frame that identifies which Network layer protocol is being used for the frame. MAC : (media access control) provide physical addressing and and delimiting of data according to the type of Data Link layer protocol in use. IEEE version ( IEEE 802.3 (MAC sub-layer) “Interact with physical layer” + IEEE 802.2 (LLC sub-layer) “Interact with Internet layer” ) Physical Layer IEEE 802.2 Logical Link Control sub-layer IEEE 802.3 Media Access Control sub-layer IEEE 802.3 Physical Layer Data-Link Layer Ethernet II

40. Layer 1 - The Physical Layer It’s responsible for all Physical properties of the network : 1. Cable length. 2. Cable type. 3. Bit rate. 4. Voltage levels. 5. H/W interface types. 7 Application 6 Presentation 5 Session 4 Transport 3 Network 2 Data Link 1 Physical

41. Encapsulating Data Transport Data Link Physical Network Upper Layer Data TCP Header DataIP Header DataLLC Header 0101110101001000010 DataMAC Header Presentation Application Session Segment Packet Bits Frame FCS Protocol Data Unit (PDU )

42. Upper Layer Data De-encapsulating Data LLC Hdr + IP + TCP + Upper Layer Data MAC Header IP + TCP + Upper Layer Data LLC Header TCP+ Upper Layer Data IP Header Upper Layer Data TCP Header 0101110101001000010 Transport Data Link Physical Network Presentation Application Session

43. Protocols Ethernet IP IPX TCP UDP TFTP FTP TELNET SNMP DHCP DNS SMTP PPP Frame relay ATM HDLC X.25

44. Commands Ipconfig/all Ipconfig/release Ipconfig/renew Ping Tracert nslookup

45. Port Numbers TCP Port Numbers FTPFTP Transport Layer TELNETTELNET DNSDNS SNMPSNMP TFTPTFTP SMTPSMTP UDP Application Layer 21 23 25 53 69 161 RIPRIP 520

46. Send SYN (seq=100 ctl=SYN) SYN received Send SYN, ACK (seq=300 ack=101 ctl=syn,ack) Established (seq=101 ack=301 ctl=ack) Host AHost B 1 2 3 SYN received TCP Three Way Handshake/Open Connection

47. Address Resolution Protocol Map IP Ethernet Local ARP 172.16.3.1 IP: 172.16.3.2 Ethernet: 0800.0020.1111 IP: 172.16.3.2 Ethernet: 0800.0020.1111 172.16.3.2 IP: 172.16.3.2 = ??? I heard that broadcast. The message is for me. Here is my Ethernet address. I need the Ethernet address of 176.16.3.2.

48. Reverse ARP Map Ethernet IP Ethernet: 0800.0020.1111 IP: 172.16.3.25 Ethernet: 0800.0020.1111 IP: 172.16.3.25 Ethernet: 0800.0020.1111 IP = ??? What is my IP address? I heard that broadcast. Your IP address is 172.16.3.25.

49. IPv4 : 32 bit in decimal format IPv6 : 128 bit in hexadecimal format DLCI:10 bit MAC address:48 bit

50. IP Address classes

51. Private IP Addresses

52. Subnetting What is the subnetwork address for a host with the IP address 200.10.5.68/28? A. 200.10.5.56 B. 200.10.5.32 C. 200.10.5.64 D. 200.10.5.0

53. Subnetting What is the broadcast address for a host with the IP address 192.168.221.37 255.255.255.248? A. 192.168.221.40 B. 192.168.221.33 C. 192.168.221.36 D. 192.168.221.39

54. VLAN = Broadcast Domain = Logical Network (Subnet) VLAN Overview Segmentation Flexibility Security

55. Each logical VLAN is like a separate physical bridge. VLANs can span across multiple switches. Trunks carry traffic for multiple VLANs. Trunks use special encapsulation to distinguish between different VLANs. VLAN Operation

56. 802.1Q Frame

57. WIRELESS LANS IEEE standard 802.11 defines the specifications for wireless LANs (WLANs). –Support ad hoc or infrastructure topologies

58. AD HOC WLAN consists of two or more wireless devices communicating directly with each other

59. INFRASTRUCTURE WIRELESS uses a wireless device called an access point between wireless devices and a standard cabled network.

60. FIREWALL SECURITY Firewalls protect a network from unauthorized access. Firewalls use several methods to examine network traffic for potential threats: –Packet filtering –Port filtering

61. NAT NAT is a routing technique that enables computers with private IP addresses to connect to the Internet. The NAT router maps private to public addresses and vice versa. Security feature of NAT –Hides hosts on private networks

62. NAT MAPPING METHODS NAT routers can map private and public addresses using one of three methods: –Static One-to-one mapping (registered to unregistered), requiring many registered IP addresses –Dynamic Many unregistered addresses mapped to one or more registered addresses –Overload Many unregistered addresses to one or more registered addresses using ports to differentiate connections

63. STATIC NAT

64. DYNAMIC NAT

65. Overload

66. PHYSICAL LAYER WAN CONNECTIONS Physical layer WAN connections use the following technologies: –Leased lines –Circuit switching –Packet/cell switching

67. WAN Connection Types  Point to Point or dedicated connection  Benefits: High speed up to 45 Mbps Secure  Disadvantages: High expensive Limited availability

68. WAN Connection Types  Dedicated circuit path must exist between sender and receiver for the duration of the call.  Examples: Dial up ISDN

69. Dial up  Benefits: Low cost  Disadvantages: Low speed (56Kpbs)

70. ISDN

71. The Integrated Services Digital Network (ISDN) uses the PSTN network. Uses circuit switching technology. Two main types of ISDN services: Basic Rate Interface (BRI) Primary Rate Interface (PRI)

72. BRI The ISDN BRI is referred to as 2B + 1D. BRI has –2 channels for data, known as B channels –1 channel for control (out-of-band signaling), known as a D channel Each 64-Kbps B channel can operate independently or can be combined to offer a 128-Kbps transmission rate.

73. PRI The ISDN PRI service consists of –23 channels for data, known as B channels –1 channel for control (out-of-band signaling), known as a D channel

74. PACKET SWITCHED WAN Benefits: High speed up to 45 Mbps Not Secured Disadvantages: Low cost High availability Examples: X.25 Frame relay

75. FRAME RELAY Frame relay is a data-link layer protocol that –Uses Permanent Virtual Circuit (PVC) and Switched Virtual Circuit (SVC) connections –Uses Data Link Control Identifier (DLCI) values to identify connections –Supports data rates from 56 Kbps up to 45Mbps

76. cell switching WAN technology Asynchronous Transfer Mode (ATM) is a cell switching WAN technology. It is designed to carry voice, data, and video traffic. ATM uses fixed 53-byte cells. It supports data rates from 56 Kbps up to 45Mbps

77. Broad band Technologies DSL CATV satellite

78. DSL Digital Subscriber Line (DSL) technology offers higher transfer rates over standard telephone lines. DSL achieves higher data rates by using higher frequency ranges. Two types:  ADSL :Asymmetric Digital Subscriber Line Download speed more faster than upload speed  SDSL:symmetric Digital Subscriber Line Download speed equal upload speed

79. CATV Cable television (CATV) networks use broadband signaling. Multiple channels occupy a single cable. CATV uses asymmetrical transmission.

80. CATV CONNECTION

81. Satellite Satellite uses asymmetrical transmission. Upload speed 512Kbps Download speed 2.048Mbps Two methods: One way Two way

82. WAN Encapsulation protocols Leased line: PPP, HDLC Circuit switched : PPP, HDLC Packet switched : X.25, Frame relay Cell switched : ATM