Mid Term Study Guide - CSchulz0618/Network-Fundamentals GitHub Wiki

OSI Model layers

  • The layers are Layer 1—Physical; Layer 2—Data Link; Layer 3—Network; Layer 4—Transport; Layer 5—Session; Layer 6—Presentation; Layer 7—Application.

4 common LAN Topologies

  • Bus
  • Star - Most Used
  • Ring
  • Mesh

Difference between a Network Hub and Network Switch

  • A Hub is a networking device that allows you to connect multiple PCs to a single network
  • A Switch connects various devices together on a single computer network.

Broadcast Domain

  • A logical division of a computer network, in which all nodes can reach each other by broadcast at the data link layer.

Default Gateway

  • A default gateway makes it possible for devices in one network to communicate with devices in another network.

Purpose and function of ARP

  • The job of ARP is essentially to translate 32-bit addresses to 48-bit addresses and vice versa. This is necessary because IP addresses in IP version 4 (IPv4) are 32 bits, but MAC addresses are 48 bits. ARP works between Layers 2 and 3

IPv4 Addresses

  • IPv4 addresses are 32-bit numbers that are typically displayed in dotted-decimal notation

IPv6 Addresses

  • An IPv6 address is a 128-bit alphanumeric value that identifies an endpoint device in an Internet Protocol Version 6 (IPv6) network.

Network Address Translation (NAT)

  • A process that enables one, unique IP address to represent an entire group of computers.

Role of subnet mask

  • A subnet mask is used to divide an IP address into two parts. One part identifies the host (computer), the other part identifies the network to which it belongs

Identifying the Network Address (all 0's in Host ID)

Identifying the Broadcast Address (all 1's in the Host ID)

Reserved "private" IP addresses