The final stage of the standardization process in which a solution is adopted as a standard.
Acknowledgement message sent by the receiving computer in a connection-oriented transmission.
American National Standards Institute. The coordinating organization for the U.S. national system of technical and non-technical standards. ANSI accepts standards developed by other organizations and publishes them as American standards and coordinates development of voluntary national standards that comply with international recommendations.
Application layer (DoD and Internet)
Combines the OSI model Application, Presentation, and Session layers.
Application layer (OSI)
The network layer that houses the applications that allow users to access the network.
Transmissions in which no response from the receiver is required.
Transmissions that require an acknowledgement of receipt from the receiving computer.
Resizing the data to speed transmission.
Security measure to prevent data from being read by unintended recipients.
Data Link layer (Internet Model)
Internet model layer equivalent to the OSI model Data Link layer. Also known as the Network Interface layer.
Data Link layer (OSI model)
The layer of the OSI model responsible for transmitting data over the network cable. Also called the Network Interface layer.
Formatting data so that it is readable by the recipient.
The process of “bookmarking” packets to allow for sessions to be recovered.
Reliable transport method
A transmission that ensures the error-free receipt of packets.
Request for Comment. The documents in which formal standards are published.
The process of determining the path required to deliver packets to their destination.
The protocol used by routers to define how the routing path is chosen.
A table stored in memory on a router that keeps track of known networks and the appropriate port to use to reach each network.
The process that handles billing for sessions.
The process that sets up the parameters of the connection between computers.
Session layer (OSI)
The network layer that controls the communication.
The process that closes down the connection between computers.
Simple Mail Transfer Protocol. A communication protocol used to define how e-mail is sent and received.
Data flows in only one direction.
A routing technique in which the routing information is included in the packet being routed.
The formal process by which standards are developed.
Transmission Control Protocol/Internet Protocol, the protocol used by the Internet. Also technically known as the Department of Defense (DoD) model.
Information that is added to the end of a data packet.
The physical conduit over which data travels within a network.
Transmission Control Protocol. The protocol used to create connection-oriented services in the TCP/IP model.
Transport layer (DoD and Internet)
The network layer responsible for moving data, ensuring that it is received without errors. DoD and Internet model layer equivalent to the OSI Transport layer.
Transport layer (OSI)
The network layer responsible for moving data, ensuring that it is received without errors.
User Datagram Protocol. The protocol used to create connectionless services in the TCP/IP model.
Communication from one layer to the layer above or below on the same device.
2.1.1. Compare formal and de facto standards.
A formal standard is one that has been defined by one of the standards organizations, and they take several years to develop. De facto standards are standards that are supported by several vendors but have no official standing. De facto standards often become formal standards after they have been widely accepted.
2.1.2. Why are standards important to an industry segment like networking?
Standards help to ensure compatibility between different vendors’ products, spur competition, and keep prices reasonable.
2.1.3. List the major standards organizations relating to data communications, networking, and the Internet.
American National Standards Institute (ANSI)
Institute of Electrical and Electronics Engineers (IEEE)
Institution of Electrical Engineers (IEE)
International Organization for Standardization (ISO)
International Telecommunications Union (ITU)
International Telecommunications Union-Telecommunications Group (ITU-T)
Internet Engineering Task Force (IETF)
2.2.1. List and describe the seven OSI model layers.
Application: End-user and application access to the network.
Presentation: Formats data for presentation to the use or for transmission on the network.
Session: Initiates, maintains, and terminates logical sessions, also manages dialog control and data separation.
Transport: Deals with end-to-end issues and establishes, maintains, and terminates connections.
Network: Manages logical addresses and routing.
Data Link: Manages physical transmission circuit, responsible for physical addressing, and translates packets into frames.
Physical: Responsible for physical connection and data communication.
2.2.2. List and describe common IEEE Physical layer standards.
Ethernet 802.3, common wired network standard supporting speeds up to 10 Gbps.
Token Ring 802.5, standard initially developed by IBM and no longer in common use.
WiFi 802.11, wireless standard that includes several detailed standards such as 802.11b and 802.11g.
2.3.1. Compare the OSI, TCP/IP (or DoD), and Internet models.
The Process (DoD) and Application (Internet) layers are equivalent to the OSI Application, Process, and Session layers.
The Host-to-Host (DoD) and Transport (Internet) layers are equivalent to the OSI Transport layer.
The Internet (DoD) and Network (Internet) layers are equivalent to the OSI Network layer.
The Network Interface (DoD) and Data Link (Internet) layers are equivalent to the OSI Data Link layer.
The Physical (Internet) layer is equivalent to the OSI Physical layer. The DoD model does not have an equivalent layer.
2.3.2. How are Internet layers organized into groups?
When designing a network, layers are often closely coupled and can be thought of in three groups: the Hardware layers (Physical and Data Link), the Internetwork layers (Network and Transport), and the Application layer. These groupings apply to the OSI model and Internet model but apply less to the TCP/IP model since it doesn’t have a Physical layer.
1. A de facto standard is one that emerges in the marketplace but has no official standing. True or false?
2. What standards body developed the OSI model?
3. Which of the following is used to develop and publish Internet standards?
4. ANSI is a U.S. standards-making body. True or false?
5. Which layer of the OSI model is responsible for routing?
(A) Network layer
6. Which of the following terms is used to describe a connection where both ends are able to communicate simultaneously?
7. The connectors that are used to attach a NIC to a network cable are defined at what layer of the OSI model?
(D) Physical layer
8. What is a MAC address?
(A) the globally unique address hard-coded on a network adapter
9. The Internet network model consists of how many layers?
10. What is the most commonly used network physical standard?
11. Which of the following are associated most closely with the OSI model Application layer?
(A) Email services
12. Which OSI model layer is NOT represented in the DoD network model?
13. Which protocol is most closely associated with the Internet model Internet layer?
14. Which Host-to-Host layer protocol provides connection-oriented service?