Week 02_CLO1 – Explaining Network Protocols and Standards Principles.pptx

CNS 2103: Networking Fundamentals Week 2: CLO1 – Explaining Network Protocols and Standards Principles Delivery Outline 2 Computer Networks W...

CNS 2103: Networking Fundamentals Week 2: CLO1 – Explaining Network Protocols and Standards Principles Delivery Outline 2 Computer Networks W1: CLO1 - Explaining modern network technologies principles W2: CLO1 - Explaining network protocols and standards principles W3: CLO2 – Classifying network physical connectivity W4: CLO2 – Implementing media access control, and data link communication W5: CLO2 – Implementing Ethernets, and switched networks W6: CLO3 – Implementing Network layer IP protocols W7-8: CLO3 – Implementing IPv4 subnetting for network segmentation W9: CLO3 – Implementing IPv6 addressing W10: CLO4 – Classifying transport layer protocols operation for end-to-end communication W11: CLO4 – Classifying application layer protocols operation in end-user applications W12: CLO4 – Implementing network hardening features to enhance security W13-14: CLO2-4 – Designing and simulating a small network W15: CLO2-4 – Troubleshooting internetworking Devices Week 2 CLO1 – Protocols and Models  Protocols and Models 4 Objectives Upon completing this chapter, the learner should be able to: The Rules and Communication Fundamentals Protocols and Services. (Chapter 9 of Textbook) Understanding the purpose of network models. (Chapter 9 of Textbook) Understanding the OSI Model. (Chapter 9 of Textbook) Layers 1 to 7 of the OSI model. (Chapter 9 of Textbook) Understanding the TCP/IP model. (Chapter 10 of Textbook) Overview of the TCP/IP layers. (Chapter 10 of Textbook) Understanding the Application, Transport, Internet and Network Access layers of the TCP/IP model. (Chapter 10 of Textbook) Data encapsulation. (Chapter 9 of Textbook) Local Addressing. (Chapter 2 of Textbook)  Protocols and Models 5 The Rules The following video will explain how devices use networking protocols to see themselves and how they use those protocols in communicating with other devices. Devices in a Bubble (Video)  Protocols and Models 6 Communication Fundamentals Networks can vary in size and complexity. It is not enough to have a connection; devices must agree on “how” to communicate. There are three elements to any communication: Message source (sender) - Message sources are people, or electronic devices, that need to send a message to other individuals or devices. Message Destination (receiver) - The destination receives the message and interprets it. Channel - This consists of the media that provides the pathway over which the message travels from source to destination  Protocols and Models 7 Network Protocol Requirements Common computer protocols must be in agreement and include the following requirements: Message encoding Message formatting and encapsulation Message size Message timing Message delivery options Watch this video on Network Protocols Check Your Understanding 1. Login to NetAcad: https://Netacad.com2. Quiz link: https://contenthub.netacad.com/itn-dl/3.1.12  Protocols and Models 9 Network Protocol Functions Network protocols define a common set of rules. Can be implemented on devices in: Software Hardware Both Protocols have their own: Function Format Rules  Protocols and Models 10 Network Protocol Functions Devices use agreed-upon protocols to communicate. Protocols may have one or functions.  Protocols and Models 11 Network Protocol Functions Networks require the use of several protocols. Each protocol has its own function and format  Protocols and Models 12 Understanding the purpose of network models Organizations need to communicate with systems owned by other organizations. There is no guarantee that all organizations use the same equipment hardware and software. If systems utilized proprietary software and protocols, then this would only allow communication with other devices from the same manufacturer or those manufacturers that had access to those protocols. The solution is to create a standard model which is made publicly available for all to use Check Your Understanding 1. Login to NetAcad: https://Netacad.com2. Quiz link: https://contenthub.netacad.com/itn-dl/3.2.4  Protocols and Models 14 TCP/IP Protocol Example TCP/IP protocols operate at the application, transport, and internet layers. The most common network access layer LAN protocols are Ethernet and WLAN (wireless LAN).  Protocols and Models 15 TCP/IP Protocol Suite TCP/IP is the protocol suite used by the internet and includes many protocols.  Protocols and Models 16 TCP/IP Protocol Suite A web server encapsulating A client de-encapsulating the and sending a web page to a web page for the web client. browser Check Your Understanding 1. Login to NetAcad: https://Netacad.com2. Quiz link: https://contenthub.netacad.com/itn-dl/3.3.6  Protocols and Models 18 Open Standards Open standards encourage: interoperability competition innovation Standards organizations are: vendor-neutral non-profit organizations established to develop and promote the concept of open standards.  Protocols and Models 19 Open Standards Standards organizations involved with the development and support of TCP/IP include: IANA ICANN Check Your Understanding 1. Login to NetAcad: https://Netacad.com 2. Quiz Link: https://contenthub.netacad.com/itn-dl/3.4.5 Understanding the purpose of network models  Protocols and Models 22 Protocols and Services In legacy networks, most systems utilized proprietary software and protocols that would only allow communication with other devices from the same manufacturer or those manufacturers that had access to those protocols. Organizations purchased their equipment from the same manufacturer throughout, and there were no real means of communicating outside of your organization. With time, networks have evolved and there is a need for to communicate with systems owned by other organizations. Therefore, standards had to be created.  Protocols and Models 23 Models providing standard Protocols and Services There are two standard network reference (layered) models that help us to understand communication between network devices and how to identify these devices through the use of IPv4 and IPv6 addresses. Open System Interconnection (OSI) Model created by the International Organization of Standards (ISO) TCP/IP Model  Protocols and Models 24 OSI Model The OSI model is a network model comprising seven individual layers, as shown in the following diagram. Each of these layers communicates to the layers adjacent to it and its equivalent layer on the receiving device. The top three layers (Application, Presentation, and Session) are referred to as the upper layers. The bottom four layers (Transport, Network, Data-Link, Physical) are referred to as the lower layers  Protocols and Models 25 OSI Model  Protocols and Models 26 OSI Model As the data goes through the OSI model on the sending device, it goes through a process called encapsulation. Encapsulation is simply taking the data from the previous layer, adding a header (and sometimes a trailer) to it, and passing it on to the next layer where the process is repeated. The header (and trailer) and data that is being passed down to the next layer is referred to as a protocol data unit (PDU) On the receiving device, the headers (and trailer) are stripped away before passing the data up to the next layer. This process is referred to as de-encapsulation.  Protocols and Models 27 Encapsulation  Protocols and Models 28 TCP/IP Model As with the OSI model, it is important for network engineers to understand the constituent components of this model. Nowadays, TCP/IP is ubiquitous in nature. It is on pretty much all network devices. Understanding the TCP/IP model, will enable you to troubleshoot networking issues on a range of devices. The TCP/IP model also maps to the OSI model. This mapping will enrich our understanding of networks, protocols and services.  Protocols and Models 29 Overview of the TCP/IP Model layers TCP/IP model has many similarities with the OSI model. They both take on a layered approach, with each layer talking to the adjacent layers and their respective layer on the destination device. Both models are open or non-proprietary standard, which means any manufacturer can use it. Most experts argue that the TCP/IP model is a truer reflection of how networking works.  Protocols and Models 30 Overview of the TCP/IP Model layers The TCP/IP model has only four layers compared to the seven layers of the OSI model. Application Layer Transport Layer Internet Layer Network Layer  Protocols and Models 31 OSI and TCP/IP Model Comparison The TCP/IP model loosely maps against the OSI model in terms of functionality, but there is no defined mapping across the two, and the following diagram should only be used as a guide.  Protocols and Models 32 Segmenting Messages Segmenting is the process of breaking up messages into smaller units. Multiplexing is the processes of taking multiple streams of segmented data and interleaving them together. Segmenting messages has two primary benefits: Increases speed - Large amounts of data can be sent over the network without tying up a communications link. Increases efficiency - Only segments which fail to reach the destination need to be retransmitted, not the entire data stream.  Protocols and Models 33 Sequencing Sequencing messages is the process of numbering the segments so that the message may be reassembled at the destination. TCP is responsible for sequencing the individual segments.  Protocols and Models 34 Protocol Data Units Encapsulation is the process where protocols add their information to the data. At each stage of the process, a PDU has a different name to reflect its new functions. There is no universal naming convention for PDUs, in this course, the PDUs are named according to the protocols of the TCP/IP suite. PDUs passing down the stack are as follows: 1. Data (Data Stream) 2. Segment 3. Packet 4. Frame 5. Bits (Bit Stream) Check Your Understanding 1. Login to NetAcad: https://Netacad.com2. Quiz Link: https://contenthub.netacad.com/itn-dl/3.6.6  Protocols and Models 36 Local Addressing Identifying devices on a local network can be done using: Hostnames MAC addresses, and IP addresses. All of these must be unique within the LAN.  Protocols and Models 37 Hostnames A computer's hostname is an easy-to-read (for humans) method of identifying a device on the network. Each device's hostname is configured by the system administrator. The hostname may be reflective of the role that the device is performing; for example, MXServer for a mail exchange server, DC1 for a domain controller, and so on. When referring to a destination device by its hostname, the sending device will need to resolve it to an IP address. Find your hostname from Command Prompt: While on your desktop, press the Windows key + R to open the run command. Type cmd and press the Enter key. In the Command Prompt, type hostname and press the Enter key.  Protocols and Models 38 IP Addresses Hostnames are human-friendly, but they are not that friendly for devices since it will not tell us whether the device is on a local or remote network. On its own, a hostname would generally be thought of as being local, but this may not always be the case. Therefore, we need to resolve hostnames to an IP address. An IP address is the network layer (layers 3) or logical address. An IP address is used to deliver packets from source device to destination device. An IPv4 address is broken down into two sections: A network part (IPv4) or Prefix (IPv6) indicates the network group which the IP address is a member. Each LAN or WAN will have the same network part. A host part (IPv4) or Interface ID (IPv6) identifies a specific device within the group and is unique for each device on the network.  Protocols and Models 39 MAC Addresses A MAC address is a means of identifying a device on the local network. It is an address that has many names. It is also referred to as a physical address, a hardware address, or a burnt-in address (BIA). A MAC address is represented as a 48-bit hexadecimal number. Find your MAC address from Command Prompt: While on your desktop, press the Windows key + R to open the run command. Type cmd and press the Enter key. In the Command Prompt, type ipconfig /all and press the Enter key. The MAC address for your network card, listed as a physical address, will be shown.  Protocols and Models 40 Devices on a Remote Network When devices are on the same Ethernet network the data link frame will use the actual MAC address of the destination NIC MAC addresses are physically embedded into the Ethernet NIC and are local addressing. The Source MAC address will be that of the originator on the link. The Destination MAC address will always be on the same link as the source, even if the ultimate destination is remote.  Protocols and Models 41 Devices on a Remote Network When the final destination is remote, Layer 3 will provide Layer 2 with the local default gateway IP address, also known as the router address The default gateway (DGW) is the router interface IP address that is part of this LAN and will be the “door” or “gateway” to all other remote locations. All devices on the LAN must be told about this address or their traffic will be confined to the LAN only. Once Layer 2 on PC1 forwards to the default gateway (Router), the router then can start the routing process of getting the information to actual destination. Check Your Understanding 1. Login to NetAcad: https://Netacad.com2. Quiz Link: https://contenthub.netacad.com/itn-dl/3.7.11 Test my understanding 1. Login to NetAcad: https://Netacad.com2. Quiz Link: Module 3 Quiz Modules 1 - 3: Basic Network Connectivity and Communications Exam 1. Login to NetAcad: https://Netacad.com2. Exam Link: Module 1-3 Exam  Thank You 800 MyHCT (800 www.hct.ac.ae 69428)