Assignment 1

 How many visitors who have visited my website?

420 visitors

With reference to Chapter 2, answer the following questions

Briefly describe the function of the equipment at layers 1, 2 and 3.

1. Layer 1: the physical layer is consists of network equipment such as USB, Bluetooth and 802.11 Wi-Fi connection. Raw data are transmitted and received in the form of bits through communication mediums such as copper cable, signal waves or light. The content of the raw data are not concerned at this layer.
2. Layer 2: the data link layer is concerned with delivery of frames between two devices in a network. It can also detect and recover collisions where a medium is used simultaneously by a device and prevent it from happening again. some examples of data link layer is PPP and Ethernet MAC
3. Layer 3: the network layer is responsible for packet forwarding by routing it to its destination through the routers. The packets are data that contains the IP address. It has a few functions including connection model, host addressing, and message forwarding. Examples are routers.

Specify 7 criteria to consider when selecting a NOS.

• Reliability - stable performance in any condition
• Performance - serves client seamlessly
• Adaptability- adapt to all different platforms
• Affordability - the cost are affordable
• Security - ability to eliminate and repel threads
• Scalability - can continue to function with the expansion of its size
• Ease - ease of use and installation

 Explain the differences between Logical address and Physical address.

The physical address is a unique 48-bit MAC address encoded in NICs by manufacturers. It is unchangeable but can be spoofed. It is associated with the data link layer. The logical address is a 32-bit IP address assigned to NICs for routing purposes between networks. The logical address operates at the network layer in the OSI model.

Explain the differences between OS and NOS.

OS or simply operating system is a system installed in a computer mainly to manage applications, hardware and connection to networks by enabling the computer on a LAN to share resources. The resources are shared using p2p model or client/server model. NOS or network operating system are system installed on a server with the basic functions of OS but it can also be used to manage network resources including user accounts, printer and file sharing across the network.

In your opinion why IPv6 is still not fully implemented.

The IPv6 address have 128bits for the entire address. One of the reasons it is still unimplemented is that there are still plenty of devices that are designed only to hold 32-bit IP address. For example, IPv6 are only introduced after windows 7 while there are still plenty of users using older devices that cannot support the length of IPv6 address. This means with the full implementation of IPv6, older devices are unable to work. Therefore the full implementation of IPv6 will take years.