Lesson 15

You are now equipped with basic knowledge about the foundation of the Internet. This module discussed network architecture essentials such as the different network diagnostic tools and their functions and connectivity hardware such as bridges, firewalls, gateways, hubs, repeaters, routers, and switches.
Key terms and concepts included OSI and Internet bandwidth technologies.
You should now be able to:

1. Explain the OSI model
2. Describe the core components of the Internet infrastructure and how they relate to each other
3. Describe the uses of hardware and software network connection devices
4. Describe the various Internet bandwidth technologies
5. Describe the purposes, functions, and features of various types of servers
6. Troubleshoot problems with Internet connectivity using various diagnostic tools

1. backbone High-speed WAN connections, servers, and ISPs that carry Internet traffic over very high-bandwidth lines.
2. OSIL: A seven-layer network model for implementing protocols and developed by the International Standards Organization (ISO).
3. Network operating system (NOS):Software that facilitates hardware and software working together as a network. Examples include Linux and Windows NT.
4. Bridge: A network connection device that isolates traffic into segments but lets the segments appear to be a single network.
5. Firewall: Network security device that blocks a specific type of data or prevents data from specified sources from entering the network.
6. Hub: Interconnects multiple devices (in a minimum of three) in a network. Enables distribution of information among connected devices.
7. Repeater: Physical layer device that extends the length of a network segment. A repeater receives and transmits signals and duplicates them onto another network segment.
8. Router: A device that forwards packets and filters traffic, based on protocol-specific software address, source and destination port numbers.
9. Switch: A device used to connect network segments with high usage percentages. A switch offers higher performance than bridges or routers and is used to create virtual LANS.
10. Pipe: A transmission wire that passes data through a network. The size of a pipe is measured in how many bits, or binary digits, it can transmit per second.
11. ATM: Asynchronous Transfer Mode (ATM) is a pipe protocol that uses fixed-size, very high-speed, high-capacity packet relay technology.
12. Frame Relay: A high-speed networking protocol for connecting multiple LANs across remote distances. Frame Relay is a packet switching protocol.
13. ISDN: Integrated Services Digital Network is a pipe protocol that operates basic communication service over regular phone lines and provides 128 kbps. ISDN uses special switching techniques to obtain higher bandwidth from telephone lines.
14. Point-to-Point Protocol (PPP): Point-to-Point protocol provides dial-up access over serial lines.
15. X.25: A pipe protocol that provides connection-oriented technology for transmission over error-prone facilities.
16. PING: A network diagnostic tool used to test whether a remote host can be reached from a specific computer.
17. Winipcfg: A Windows specific utility used to provide information about IP address, network connections, and Internet resources.
18. TRACERT: A trace route utility that shows routing and delay times. Tracert tools are available as either command line tools or as graphical tools.
19. NETSTAT: A utility that displays a list of server-side TCP/IP connections. Netstat is also used to obtain network statistics; display the contents of the local routing table; and obtain statistics on a particular protocol such as UDP.

In the next module, you will learn about Internet protocols.

Click the link below to read about estimating Web server transfer load and bandwidth technologies.
Estimating Server Transfer Load

Click the link below to learn about evaluating the DARPA and OSI models of a network.
Network Model Layers

Click the Quiz link below to check your knowledge of network hardware and software and troubleshooting solutions.
Network Devices - Quiz