Network+ Exam Prep: Ethernet Networking Standards
As discussed in Chapter 1, "Introduction to Networking," a topology defines the structure of a network, and network standards define how it works. As early as the 1970s, it was apparent that networks were going to play a large role in future corporate environments. Many manufacturers saw the computing and network trend and became increasingly active in network component development. These companies realized that for their products to work together, standards would be necessary to ensure compatibility. The task of producing the standards fell to an international body called the Institute of Electrical and Electronics Engineers (IEEE).
The IEEE developed a set of standards called the 802 project. These standards are still used today, although there have been many changes and additions along the way. By using the standards defined by the IEEE, manufacturers can be sure that their products will work with products from other companies that adhere to the standards.
Some of the IEEE 802 standards define only certain technologies, whereas others, such as the 802.3 standard, define entire networking systems. The following are some of the most important IEEE 802 standards:
- 802.1, bridging and management—Defines the systems for managing networks. 802.1 specifies technologies for making sure that the network is available to users and responding to requests. It defines internetwork communications standards between devices and includes specifications for routing and bridging.
- 802.2, the LLC sublayer—Defines specifications for the Logical Link Control (LLC) sublayer in the 802 standard series.
- 802.3, CSMA/CD—Defines the carrier-sense multiple-access with collision detection (CSMA/CD) media access method used in ethernet networks. This is the most popular networking standard used today.
- 802.4, a token passing bus (rarely used)—Defines the use of a token-passing system on a linear bus topology.
- 802.5, token ring networks—Defines token ring networking, also known as token ring access.
- 802.6, metropolitan area network (MAN)—Defines a data transmission method called distributed queue dual bus (DQDB), which is designed to carry voice and data on a single link.
- 802.7, Broadband Technical Advisory—Defines the standards and specifications of broadband communications methods.
- 802.8, Fiber-Optic Technical Advisory—Provides assistance to other IEEE 802 committees on subjects related to the use of fiber optics.
- 802.9, integrated voice and data networks—Defines the advancement of integrated voice and data networks.
- 802.10, network security—Defines security standards that make it possible to safely and securely transmit and exchange data.
- 802.11, wireless networks—Defines standards for wireless LAN communication.
- 802.12, 100BaseVG-AnyLAN—Defines standards for high-speed LAN technologies.
For the Network+ exam and day-to-day real-life networking, some of these standards are more important than others. This chapter primarily focuses on the 802.3 ethernet standards and their characteristics, such as access methods (CSMA/CD), signaling type (baseband/broadband), their speeds, and the distances they support. Chapter 7, "Wireless Networking," discusses 802.11 wireless standards.