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VA Technical Reference Model v 21.8

Carrier Sense Multiple Access with Collision Detection (CSMA/CD)
Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Standard or Specification

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Technologies must be operated and maintained in accordance with Federal and Department security and privacy policies and guidelines. More information on the proper use of the TRM can be found on the TRM Proper Use Tab/Section.

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Description: Carrier sense multiple access with collision detection (CSMA/CD), is a network multiple access method in which carrier sensing is used, but nodes attempt to avoid collisions by transmitting only when the channel is sensed to be `idle`. When they do transmit, nodes transmit their packet data in its entirety.

Institute of Electrical and Electronics Engineers (IEEE) 802.3: Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method and Physical Layer Specifications:
Ethernet Local Area Network (LAN) operation is specified for selected speeds of operation from 1 Mb/s to 10 Gb/s using a common media access control (MAC) specification and management information base (MIB). The CSMA/CD MAC protocol specifies shared medium (half duplex) operation, as well as full duplex operation. Speed specific Media Independent Interfaces (MIIs) allow use of selected Physical Layer devices (PHY) for operation over coaxial, twisted pair or fiber optic cables. System considerations for multi-segment shared access networks describe the use of Repeaters, which are defined for operational speeds up to 1000 Mb/s. LAN operation is supported at all speeds. This specification includes:
  • 100 Mb/s baseband network, type 100BASE-T (any of several Fast Ethernet standards for twisted pair cables)
  • 1000 megabyte (Mb)/s baseband network
  • 10 gigabyte (Gb)/s baseband network
  • Ethernet for subscriber access networks
Technology/Standard Usage Requirements: Users must ensure their use of this technology/standard is consistent with VA policies and standards, including, but not limited to, VA Handbooks 6102 and 6500; VA Directives 6004, 6513, and 6517; and National Institute of Standards and Technology (NIST) standards, including Federal Information Processing Standards (FIPS). Users must ensure sensitive data is properly protected in compliance with all VA regulations. Prior to use of this technology, users should check with their supervisor, Information Security Officer (ISO), Facility Chief Information Officer (CIO), or local Office of Information and Technology (OI&T) representative to ensure that all actions are consistent with current VA policies and procedures prior to implementation.
Section 508 Information:
Decision: View Decisions

Decision Source: TRM Mgmt Group
Decision Process: One-VA TRM v21.3
Decision Date: 03/26/2021
Introduced By: TRMSP
Standards Body: IEEE
- The information contained on this page is accurate as of the Decision Date (03/26/2021).