Unit 3 Assignment 1 Osi Model

Layer 3: Network - The way that the data will be sent to the recipient device is determined in this layer. Logical protocols, routing and addressing are handled here.

The fifth layer is the session layer this establishes a connection,this layer makes and sets up the connection using co ordinates and could terminate conversations links. the session layer produces services that make authentication after an interruption and not only that but it can reconnect.and as well as the transporting layer it can also have the TCP and the UDP can provide services for all most all applications.An application layer is an abstraction layer that specifies the shared protocols and interface methods used by hosts in a communications network. The application layer abstraction is used in both of the standard models of computer networking; the Internet Protocol Suite (TCP/IP) and the Open Systems Interconnection model (OSI model).Although both models use the same term for their respective highest level layer, the detailed definitions and purposes are different.In TCP/IP, the application layer contains the communications protocols and interface methods used in process-to-process communications

request to the network device to establish the connection, and then sends data to the device so it can be

4. Which of the following protocols is a connection-oriented protocol that operates at the transport layer of the OSI model and supports reliable connections?

IPv6 uses NDP (Neighbor Discovery Protocol) to find the MAC address. NDP manages interaction between nodes via message exchanges. These messages provide the data necessary for the processes of host auto configuration and packet transmission on a local link. Host auto configuration involves separate tasks of Parameter discovery, address auto configuration and duplicate address detection. Packet discovery is facilitated through router discovery process. It obtains the necessary parameters required for host configuration. Duplicate address detection is used to detect the presence of duplicate addresses on the same link. Packet transmission process requires data which can be obtained by router discovery, prefix discovery, address resolution, neighbor

Layer 3: Network Layer– This layer determines how the data will be transmitted between networks. Packets are routed to the unique network device addresses. At this layer, if large data is not able to be sent through the network, they are broken down into smaller pieces.

Network Layer: directs the source-to-destination delivery of a packet, possibly across multiple networks. It ensures that each packets gets from its point of origin to its destination.

In a nutshell, the OSI model is divided into seven layers that are responsible for moving data up and down the stack; from the user, all the way down to the physical layer where the cables reside and then back up again. Each layer uses its own protocols and is responsible for carrying out its assigned function. These layers include the Application Layer (layer 7), Presentation Layer (layer 6), Session Layer (layer 5), Transport Layer (layer 4), Network Layer (layer 3), Data Link Layer (layer 2) and the Physical Layer (layer 1). See Figure 3-3 for illustration of OSI model.

Physical layer : The Physical layer is the lowest layer of the internet model and is concerned with the transmission and reception of the unstructured raw bit stream. It describes the electrical/optical, mechanical, and functional interfaces to the physical medium, and carries the signals for all of

A)The packet number is 32 that contains the status code and phrase associated with the response to the HTTP GET request.

The third layer of the OSI model is the network layer and is where the routers and layer 3 switches would be. This layer is responsible for controlling subnets and deciding which path the data should take based on certain conditions. This layer is also responsible for IP (internet protocol) addresses, this includes both IPv4 and IPv6 addresses. Packets in this layer identify where the traffic originated (source IP address) and where it is going (destination IP address) (Gibson 166). In short, the OSI layer three network layer is responsible for connections, host addressing, and message forwarding. Protocols that operate on this layer are IPsec and ICMP.

Given the highly mobile aspects of the company's workforce, it is recommended that between the options of Dynamic Host Configuration Protocol (DHCP) using Secured Sockets Layer (SSL) or IPSec, that the former is much more aligned to their business strategies today and future growth. The intent of these recommendations is to provide guidance on how to best implement DHCP over a SSL so that Voice over Internet Protocol (VoIP) can also be used.

There are seven layers in the OSI Model, only four in the TCP/IP model. This is because TCP/IP assumes that applications will take care of everything beyond the Transport layer. The TCP/IP model also combines the OSI 's Physical and Data Link layers together into the Network Access Layer. Internet Protocol is not concerned about the hardware underneath, as long as the computer can send IP packets over the connection.

A given layer in the OSI model generally communicates with three other OSI layers: the layer directly above it, the layer directly below it, and its peer layer in other networked computer systems. The data link layer in System A, for example, communicates with the network layer of System A, the physical layer of System A, and the data link layer in System B. The following figure illustrates this example.

The network layer is capable of sending broadcast requests, manages routing, processing received messages. Outgoing frames will makes use of adequate key based on routing, if the key is available; otherwise, it uses the network key which will be used to protect the payload