Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Internetworking Chapter 2 Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Technology Describe Network communications using layered models Compare and contrast key characteristics of LAN environments Describe the components of network devices Evaluate rules for packet control Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Agenda Internetworking Basics Internetworking Model The OSI Reference Model Ethernet Networking Wireless Networking Data Encapsulation Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Possible causes of LAN traffic congestion are Too many hosts in a broadcast domain Broadcast storms Multicasting Low bandwidth Adding hubs for connectivity to the network A large amount of ARP or IPX traffic (IPX is a Novell Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Network Segmentation Collision domain Broadcast domain Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Two advantages of using routers in your network are They don’t forward broadcasts by default. They can filter the network based on layer 3 (Network layer) information (i.e., IP address). Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Four router functions in your network can be listed as Packet switching Packet filtering Internetwork communication Path selection Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Internetworking Model The Layered Approach Advantages of Reference Models It divides the network communication process into smaller and simpler components, thus aiding component development, design, and troubleshooting. It allows multiple-vendor development through standardization of network components. It encourages industry standardization by defining what functions occur at each layer of the model. It allows various types of network hardware and software to communicate. It prevents changes in one layer from affecting other layers, so it does not hamper development. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

The OSI Reference Model The upper layers Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. The lower layers Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Layer functions Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Application Layer The Application layer of the OSI model marks the spot where users actually communicate to the computer. Sample -> World Wide Web (WWW) E-mail gateways Electronic data interchange (EDI) Special interest bulletin boards Internet navigation utilities Financial transaction services13 Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

The Presentation Layer It presents data to the Application layer and is responsible for data translation and code formatting. This layer is essentially a translator and provides coding and conversion functions. A successful data-transfer technique is to adapt the data into a standard format before transmission. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. The Session Layer The Session layer is responsible for setting up, managing, and then tearing down sessions between Presentation layer entities. This layer also provides dialogue control between devices, or nodes. It coordinates communication between systems, and serves to organize their communication by offering three different modes: simplex, half duplex, and full duplex. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. The Transport Layer The Transport layer segments and reassembles data into a data stream. Services located in the Transport layer both segment and reassemble data from upper-layer applications and unite it onto the same data stream. They provide end-to-end data transport services and can establish a logical connection between the sending host and destination host on an internetwork. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. The Transport layer is responsible for providing mechanisms for multiplexing upper-layer applications, establishing sessions, and tearing down virtual circuits. The Transport layer can be connectionless or connection-oriented. Some of you are probably familiar with TCP and UDP already. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Flow Control Data integrity is ensured at the Transport layer by maintaining flow control and by allowing users to request reliable data transport between systems. The segments delivered are acknowledged back to the sender upon their reception. Any segments not acknowledged are retransmitted. Segments are sequenced back into their proper order upon arrival at their destination. A manageable data flow is maintained in order to avoid congestion, overloading, and data loss. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Connection-Oriented Communication a call setup, or a three way handshake Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Transmitting segments with flow control Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Windowing Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Acknowledgments It guarantees that the data won’t be duplicated or lost. This is achieved through something called positive acknowledgment with retransmission a technique that requires a receiving machine to communicate with the transmitting source by sending an acknowledgment message back to the sender when it receives data. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Transport layer reliable delivery Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. The Network Layer The Network layer (also called layer 3) manages device addressing, tracks the location of devices on the network, and determines the best way to move data, which means that the Network layer must transport traffic between devices that aren’t locally attached. Two types of packets are used at the Network layer: Data packets : routed protocol Route update packets : routing protocol Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Routing table used in a router Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Here are some points about routers that you should really commit to memory: Routers, by default, will not forward any broadcast or multicast packets. Routers use the logical address in a Network layer header to determine the next hop router to forward the packet to. Routers can use access lists, created by an administrator, to control security on the types of packets that are allowed to enter or exit an interface. Routers can provide layer 2 bridging functions if needed and can simultaneously route through the same interface. Layer 3 devices (routers in this case) provide connections between virtual LANs (VLANs). Routers can provide quality of service (QoS) for specific types of network traffic. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. The Data Link Layer The Data Link layer provides the physical transmission of the data and handles error notification, network topology, and flow control. The Data Link layer formats the message into pieces, each called a data frame, and adds a customized header containing the hardware destination and source address. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Data Link layer with the Ethernet and IEEE specifications. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

The IEEE Ethernet Data Link layer has two sublayers: Media Access Control (MAC) 802.3 Defines how packets are placed on the media. Contention media access is “first come/first served” access where everyone shares the same bandwidth—hence the name. Physical addressing is defined here, Logical Link Control (LLC) 802.2 Responsible for identifying Network layer protocols and then encapsulating them. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Switches and Bridges at the Data Link Layer Layer 2 switching is considered hardware-based bridging because it uses specialized hardware called an application-specific integrated circuit (ASIC). Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. The Physical Layer we find that the Physical layer does two things: It sends bits and receives bits. Bits come only in values of 1 or 0—a Morse code with numerical values. The Physical layer specifies the electrical, mechanical, procedural, and functional requirements for activating, maintaining, and deactivating a physical link between end systems. This layer is also where you identify the interface between the data terminal equipment (DTE) and the data communication equipment (DCE). Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Hubs at the Physical Layer A hub is really a multiple-port repeater. A repeater receives a digital signal and reamplifies or regenerates that signal, and then forwards the digital signal out all active ports without looking at any data. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Ethernet Networking Lecture 2-2 Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

The success of Ethernet is due to the following factors: Simplicity and ease of maintenance Ability to incorporate new technologies Reliability Low cost of installation and upgrade Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

802.3 Ethernet in Relation to The OSI Model Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. IEEE 802.x Standards Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Ethernet Technologies Mapped to the OSI model Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Ethernet Addressing We get into how Ethernet addressing works. It uses the Media Access Control (MAC) address burned into each and every Ethernet Network Interface Card (NIC). Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. MAC Address Format Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Generic Frame Format Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. IEEE 802.3 Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Ethernet II Frame Format Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Ethernet II and IEEE 802.3 Frame Format Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Media Access Control (MAC) Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

MAC Rules and Collision Detection/Backoff Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

MAC Rules and Collision Detection/Backoff Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Ethernet Timing Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Interframe Spacing Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Backoff Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Error Handling Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Types of Collisions Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. The effects of having a CSMA/CD network sustaining heavy collisions include Delay Low throughput Congestion Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Ethernet Errors Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Ethernet Errors Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. FCS Errors Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Parameters for 10 Mbps Ethernet Operation Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Manchester Encoding Examples Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Parameters for 100-Mbps Ethernet Operation Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

MLT-3 Encoding Example (100Base-TX) Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

NRZI Encoding Examples (100Base-FX) Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Parameters for Gigabit Ethernet Operation Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Actual 1000Base-T Signal Transmission Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Gigabit Ethernet Layers Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Gigabit Ethernet Media Comparison Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Parameters for 10-Gbps Ethernet Operation Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

10GBASE LX-4 Signal Multiplexing Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Wireless Networking Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Benefits of WLANs Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Evolution of Wireless LANs Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Unlicensed Frequency Bands Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Wireless Technologies Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Distance Versus Speed Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Wireless Technologies Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. In-Building WLANs Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. The IEEE 802 Standards Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. IEEE 802.11 Protocols Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. IEEE 802.11 Standards Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Data Encapsulation Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Data Encapsulation Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT.

Computer Network by P.It-arun Computer Engineering Dept, RMUTT. Summary OSI model—the seven-layer model used to help application developers design applications that can run on any type of system or network. Each layer has its special jobs and select responsibilities within the model to ensure that solid, effective communications do, in fact, occur. Remember that hubs are Physical layer devices and repeat the digital signal to all segments except the one it was received from. Switches segment the network using hardware addresses and break up collision domains. Routers break up broadcast domains (and collision domains) and use logical addressing to send packets through an internetwork. Computer Network by P.It-arun Computer Engineering Dept, RMUTT.