Overview of OSI Model

The Session Layer (Layer 5) manages and controls the dialogues (connections) between computers, establishes, manages, and terminates connections between applications.

The main components of the Presentation Layer (Layer 6) are encryption, compression, and translation services. Its role is to ensure that the data is in a usable format and to transform data into a format that the Application Layer can accept.

The main components of the Application Layer (Layer 7) are web browsers, email clients, and other applications that require network access. Its role is to provide services directly to user applications and facilitate communication between software applications and lower-level network services.

<p>The two main purposes and benefits of NAT are address conservation and security. NAT helps conserve the limited number of IPv4 addresses by allowing private IP networks to use a single public IP address for all external communications. It also adds a layer of security by hiding internal IP addresses, making it harder for attackers to directly access internal devices.</p> Signup and view all the answers

<p>For outgoing packets, the NAT device translates the internal source IP address into a public IP address. For incoming packets, the NAT device maps the destination public IP address back to the corresponding internal private IP address.</p> Signup and view all the answers

<p>The three main types of NAT are: 1) Static NAT, which maps one internal IP address to one external IP address, often used for web hosting; 2) Dynamic NAT, which maps an unregistered IP address to a registered one from a pool of available addresses, changing with each session; and 3) Port Address Translation (PAT), also known as NAT overload, which maps multiple private IP addresses to a single public IP address (or a few addresses) using different port numbers.</p> Signup and view all the answers

<p>The primary function of the Physical Layer is to handle the physical connection between devices, including the electrical, mechanical, and procedural aspects of connecting to the network.</p> Signup and view all the answers

<p>Bridges, switches, and Network Interface Cards (NICs) operate at the Data Link Layer. Their role is to detect and possibly correct errors that may occur in the Physical layer during node-to-node data transfer.</p> Signup and view all the answers

<p>The Network Layer determines the best path for data transmission using logical addressing, such as IP addresses.</p> Signup and view all the answers

<p>The two main protocols that operate at the Transport Layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol). Their function is to provide reliable, transparent transfer of data between end systems.</p> Signup and view all the answers

<p>The OSI model is a conceptual framework used to understand and standardize the functions of a telecommunications or computing system without regard to its underlying internal structure and technology.</p> Signup and view all the answers

<p>The primary function of the Network Layer is to handle the routing of data across the network, including deciding how to route packets from the source to the destination.</p> Signup and view all the answers