1. CCNA Tími 1

2. Network Icons

3. SOHO network SOHO network (small office/home office)

4. Overview of the TCP/IP Networking Model

5. Transport Layer Protocols TCP is considered connection oriented protocol and it has a build in error correction and sequencing Similar to making a phone call, example:

6. Transport Layer Protocols UDP is considered connection less protocal, it has no error connection so the application must have using the it must have it. Similar to posting a letter, exchample:

7. Internet layer Protocols IP defines logical addresses used to communicate over networks Each TCP/IP host—needs a unique address so that it can be identified in the network Example of IP addresses: 1.1.1.1, 2.2.2.2, 192.168.10.1 …………. This format is called dotted-decimal notation (DDN)

8. Example of a routed IP network

9. IP Routing Basic

10. Network Access Layer The TCP/IP model’s network access layer defines the protocols and hardware required to deliver data across some physical network.

11. Network Access Versus Data Link and Physical Layers

12. TCP/IP model step by step Step 1 Create and encapsulate the application data with any required application layer headers. For example, the HTTP OK message can be returned in an HTTP header, followed by part of the contents of a web page. Step 2 Encapsulate the data supplied by the application layer inside a transport layer header. For end-user applications, a TCP or UDP header is typically used. Step 3 Encapsulate the data supplied by the transport layer inside an Internet layer (IP) header. IP defines the IP addresses that uniquely identify each computer. Step 4 Encapsulate the data supplied by the Internet layer inside a data link layer header and trailer. This is the only layer that uses both a header and a trailer. Step 5 Transmit the bits. The physical layer encodes a signal onto the medium to transmit the frame.

13. Names of TCP/IP Messages You must know this!!!!!!! Transport layer SEGMENT Network layer PACET Data link layer FRAME Network layer BITS

14. Comparing OSI and TCP/IP

15. OSI Layers and Their Functions LayerFunctional Description 7Layer 7 provides an interface between the communications software and any applications that need to communicate outside the computer on which the application resides. It also defines processes for user authentication. 6This layer’s main purpose is to define and negotiate data formats, such as ASCII text, EBCDIC text, binary, BCD, and JPEG. Encryption is also defined by OSI as a presentation layer service. 5The session layer defines how to start, control, and end conversations (called sessions). This includes the control and management of multiple bidirectional messages so that the application can be notified if only some of a series of messages are completed. This allows the presentation layer to have a seamless view of an incoming stream of data.

16. OSI Layers and Their Functions LayerFunctional Description 4Layer 4 protocols provide a large number of services, as described in Chapter 6, “Fundamentals of TCP/IP Transport, Applications, and Security.” Although OSI Layers 5 through 7 focus on issues related to the application, Layer 4 focuses on issues related to data delivery to another computer (for instance, error recovery and flow control). 3The network layer defines three main features: logical addressing, routing (forwarding), and path determination. Routing defines how devices (typically routers) forward packets to their final destination. Logical addressing defines how each device can have an address that can be used by the routing process. Path determination refers to the work done by routing protocols to learn all possible routes, and choose the best route.

17. OSI Layers and Their Functions LayerFunctional Description 2The data link layer defines the rules that determine when a device can send data over a particular medium. Data link protocols also define the format of a header and trailer that allows devices attached to the medium to successfully send and receive data. 1This layer typically refers to standards from other organizations. These standards deal with the physical characteristics of the transmission medium, including connectors, pins, use of pins, electrical currents, encoding, light modulation, and the rules for how to activate and deactivate the use of the physical medium.

18. OSI Layering Benefits Less complex: Compared to not using a layered model, network models break the concepts into smaller parts. Standard interfaces: The standard interface definitions between each layer allow for multiple vendors to create products that fill a particular role, with all the benefits of open competition.

19. OSI Layering Benefits Easier to learn: Humans can more easily discuss and learn about the many details of a protocol specification. Easier to develop: Reduced complexity allows easier program changes and faster product development.

20. OSI Layering Benefits Multivendor interoperability: Creating products to meet the same networking standards means that computers and networking gear from multiple vendors can work in the same network. Modular engineering: One vendor can write software that implements higher layers—for example, a web browser—and another vendor can write software thatimplements the lower layers—for example, Microsoft’s built-in TCP/IP software in its OSs.

21. OSI Encapsulation and Protocol Data Units SEGMENT PACKED FRAM BITS PDU = Protocol Data Unit

22. Fundamentals of LANs The term Ethernet refers to a family of standards that together define the physical and data link layers of the world’s most popular type of LAN. speeds of 10 megabits per second (Mbps), 100 Mbps, 1000 Mbps (1 gigabit per second, or Gbps) or even 10Gbps being common today

23. Fundamentals of LANs The most commonly used Ethernet standards allow the use of inexpensive unshielded twisted-pair (UTP) cables. Fiber-optic cabling might be worth the cost in some cases, because the cabling is more secure and allows for much longer distances between devices

24. The Data Link Layer The data link layer is divided into two sub layers – The 802.3 Media Access Control (MAC) sub layer – The 802.2 Logical Link Control (LLC) sub layer Each new physical layer standard from the IEEE requires many differences at the physical layer. However, each of these physical layer standards uses the exact same 802.3 header, and each uses the upper LLC sublayer as well. Table 3-2 lists the most commonly used IEEE Ethernet physical layer standards.

25. Common Types of Ethernet

26. Typical Small Modern LAN This diagram applies to all the common types of Ethernet. The same basic design and topology are used regardless of speed or cabling type. The term LAN = Local Aria Network

27. Functions of Local Aria Networks File sharing Printer sharing File transfers Gaming Connection to the Web And many more …………………….

28. Ethernet in the early days The two first Ethernet standard where: – 10BASE2 also known as cheapernet, thin Ethernet, thinnet, and thinwire. The caballing used is coaxical connected in a bus. Maximum length 185 meters with impedance of 50 Ω – 10BASE5 also known as thick ethernet or thicknet. The caballing used is coaxical connected in a bus. Maximum length 500 meters with impedance of 50 Ω

29. Ethernet 10BASE2 Network Because the network uses a single bus, if two or more electrical signals were sent at the same time, they would overlap and collide, making both signals unintelligible.

30. The CSMA/CD algorithm A device that wants to send a frame waits until the LAN is silent—in other words, no frames are currently being sent—before attempting to send an electrical signal. If a collision still occurs, the devices that caused the collision wait a random amount of time and then try again.

31. 10BASE-T LAN Network With a Hub Hubs are essentially repeaters with multiple physical ports. That means that the hub simply regenerates the electrical signal that comes in one port and sends the same signal out every other port. Al ports on a Hub are in a single collision domain. Using Hubs solved a lot of the reliability problems that exists in bus networks.

32. UTP RJ-45 Connectors and Ports

33. Gigabit Interface Converters (GBIC) Cisco manufactures a wide range of GBICs and SFPs, for every Ethernet standard, the switch can use a variety of cable connectors and types of cabling and support different cable lengths 1000BASE-T GBIC with an RJ-45 Connector

34. TIA Standard Ethernet Cabling Pinouts The Telecommunications Industry Association (TIA) defines standards for UTP cabling, color coding for wires, and standard pinouts on the cables The picture shows two pinout standards from the TIA, with the color coding and pair numbers listed

35. Ethernet Straight-Through Cable Concept A straight-through cable is used when the devices on the ends of the cable use opposite pins when they transmit data.

36. Ethernet Crossover Cable Because both switches send on the pair at pins 3,6, and receive on the pair at pins 1,2, the cable must swap or cross the pairs For the exam, you should be well prepared to choose which type of cable (straight-through or crossover) is needed in each part of the network

37. Straight-Through and Crossover Ethernet Cables

38. Ethernet Addressing Ethernet LAN addressing identifies either individual devices or groups of devices on a LAN. Each address is 6 bytes long. Example: – D0-67-E5-3C-46-A0 or D0:67:E5:3C:46:A0

39. Ethernet Addressing Unicast Ethernet addresses identify a single LAN card. Broadcast addresses: The most often used of the IEEE group MAC addresses, the broadcast address, has a value of FFFF.FFFF.FFFF (hexadecimal notation). Multicast addresses: Multicast addresses are used to allow a group of devices on a LAN to communicate. When using IP multicasts over an Ethernet, the multicast MAC addresses used follow this format: 0100.5exx.xxxx,

40. Ethernet Framing Framing defines how a string of binary numbers is interpreted. Framing defines the meaning behind the bits that are transmitted across a network. The physical layer helps you get a string of bits from one device to another Each frame must have a way to identify the upper layer protocol to hand the data do. To do that, most data-link protocol headers, including Ethernet, have a field with a code that defines the type of protocol header that follows. Generically speaking, these fields in data-link headers are called Type fields.

41. Sending IP packets when sending IP packets, the Ethernet frame has two additional headers: ■ An IEEE 802.2 Logical Link Control (LLC) header ■ An IEEE Subnetwork Access Protocol (SNAP) header

42. Ethernet Header and Trailer Fields

43. Fundamentals of WANs Point-to-point WAN links provide basic connectivity between two points.

44. Components and Terminology

45. Serial Cabling Options

46. WAN Speed Summary

47. OSI Layer 2 for Point-to-Point WANs Wan serial interface uses HDLC to encapsulate data. HDLC needs to determine if the data passed the link without any errors; HDLC discards the frame if errors occurred HDLC needs to identify the type of packet inside the HDLC frame so the receiving device knows the packet type

48. HDLC Framing

49. Point-to-Point Protocol PPP behaves much like HDLC. The framing looks identical to the Cisco proprietary HDLC framing. There is an Address field, but the a PPP has many additional features that had not been seen in WAN data link layer (security, passwords) PPP has become the most popular and feature- rich of WAN data link layer protocols Can be used to connect CISCO and third party devises

50. Frame Relay Frame Relay networks provide more features and benefits than simple point-to-point WAN Links Frame Relay networks are multi-access networks, which means that more than two devices can attach to the network The access links run at the same speed and use the same signaling standards as do point-to-point leased lines. However, instead of extending from one router to the other, each leased line runs from one router to a Frame Relay switch.

51. Frame Relay Components

52. Frame Relay VC Concepts The logical path that a frame travels between each pair of routers is called a Frame Relay VC. VCs are called permanent virtual circuits (PVC)

53. Fundamentals of IPv4 Addressing and Routing

54. Foundation Topics Routing: The process of forwarding packets (Layer 3 PDUs). Logical addressing: Addresses that can be used regardless of the type of physical networks used, providing each device (at least) one address. Logical addressing enables the routing process to identify a packet’s source and destination. Routing protocol: A protocol that aids routers by dynamically learning about the groups of addresses in the network, which in turn allows the routing (forwarding) process to work well. Other utilities: The network layer also relies on other utilities. For TCP/IP, these utilities include Domain Name System (DNS), Dynamic Host Configuration Protocol (DHCP), Address Resolution Protocol (ARP), and ping.

55. OSI layer 3 protocols Internet Protocol (IP) IPv4/IPv6 Novell Internetwork Packet Exchange (IPX) AppleTalk Datagram Delivery Protocol (DDP) Internet Control Message Protocol (ICMP) Internet Group Multicast Protocol (IGMP) Routing Information Protocol (RIP) Address Resolution Protocol (ARP).................................

56. IP Routing

57. IP Header

58. IPv4 Header Fields

59. Classes of Networks

60. All Possible Valid Network Numbers

61. A B C All A IP addresses start with 0 All B IP addresses start with 10 All C IP addresses start with 110

62. ARP