Tag: AVB

SO – “What is all the fuss about TSN (Time Sensitive Networking)?

And now for a “way too broad” question.

This was originally entitled “Time Sensitive Networking” by Praveen here, and phrased as this:

I am aware of current Ethernet Technology and it’s non-deterministic behavior, due to CSMA-/CA/CD. I also see a lot of news around Time Sensitive Networking.

Could anyone briefly explain how TSN could change or enhance timing, synchronization, how is it related to IEEE 1588(PTP) etc ?

Since indeed this is “way too broad”, I’d rephrase it as “what is all the fuss about TSN (Time Sensitive Networking)?”

First, to put that aside:

All Ethernet link these days are full duplex, so collision avoidance such as CSMA-/CA/CD are a thing of the past since about 15 years I would say: Ethernet is not a shared media (like is air for Wi-Fi), and there simply isn’t any collision, so no need to avoid it. Did you get that “non-deterministic because of CSMA-/CA/CD” from a book or teacher? Then those would need a serious update.

(And so no, the collision risk and its avoidance mechanism is not the cause of “current Ethernet Technology and it’s non-deterministic behavior”, especially not with the word “current”.)

And this being done, here is my – way too broad and light – answer introduction pointers to this AVB/TSN topic:

About TSN (Time Sensitive Networking):

TSN is just the new name for an IEEE 802 task sub-group that was first called AVB for “Audio Video Bridging”, as you can see from here (2005 or 2008 to 2012):


Note: The Audio/Video Bridging Task Group was renamed the
“Time-Sensitive Networking Task Group” in November, 2012. Please refer
to that page for further information. The rest of this page has been
preserved it existed at that time, without some obsolete meeting

The change was made to reflect its now broader perspective: not only for Pro Audio/Video distribution use, but also to automotive, and latter industrial applications as well. So the work continues here:


(yes, I know, the look an feel of IEEE web pages really  really sucks, but that is good content though)

As a result, you’ll actually find most information about the fundamentals of TSN by googling “Ethernet AVB” rather than “Ethernet TSN”. The wikipedia page, carefully maintained by people directly involved with the technology, is a good start:


Also, as with every technology, there is a technical side, that’s the IEEE AVB->TSN group, and there is a marketing side, taking care of branding, use-cases, and (very important) certification programs to label and guarantee the interoperability of products, to have a healthy ecosystem. For AVB/TSN, this marketing side is handled by the AVnu Alliance SIG (Special Interest Group), founded in 2009:


There too, you can find a lot of information in the knowledge base section of the web site (technologies, whitepapers, specifications, FAQs): why was it made (what is the problem to solve), how does it work, what are the use cases in the various fields it targets.

Some final words:

AVB/TSN it is not a single protocol, but rather a set of protocols, put together with possible variants according to the use case. Example: originally designed with auto-configuration/plug and play’ built in (geared towards sound engineers, without the need for network engineers), its automotive profile rather use static configuration (because of reduced boot and configuration time, lesser code/hardware for reduced cost embedded devices, and you’re not going to change a car networking topology nor roles of the nodes everyday anyway).

And that makes a BIG pile of standards: the base IEEE AVB standards put together, the last one published in 2013 IIRC, where already about 1,500 pages, and TSN is now expanding that. Distribution of a common wall-clock to participants, which is a prior need to synchronization, with sub-microsecond range of precision, is a big, complex problem in itself to start with . Be it with a static clock device reference (“PTP master”) in IEEE 1588, and even more with a elected, and then constantly monitored and possibly re-elected GM (“Grand Master) via a BMCA (Best master clock algorithm) as in IEEE 802.1AS.

Also, all this require implementation not only in the end nodes, but also in the switches (bridges), which takes an active part in it at pretty much every level (clocking, but also bandwidth reservation, then admission and traffic shaping). So part of the standards are relevant to nodes, others to the bridges.

So all this is really quite big and complex, and going from 1,500 pages (which I once read from cover to cover) – and it’s now more than that – to “briefly explain how TSN could change or enhance timing, synchronization, how is it related to IEEE 1588 (PTP) etc ?” is a bit challenging… especially the “etc” part… :-)

Hope these few pointers help though.

SO – how about multicast/broadcast Audio/Video streaming over 802.11 aka Wi-Fi?

Ahhhhh… now that’s a really, really good question, originally titled as “Wi-Fi Monitor mode listening to traffic”, from pratiklodha, here.

Actually, it may have been titled as this: “how about multicast/broadcast Audio/Video streaming over 802.11 aka Wi-Fi?”, and so will I.

And now that’s an interesting topic by itself. A real, industry-wide question about the state of technology.

And here was my answer, as 802.11 state of the Art in March of 2016: – warning: as presumption as it may sound, this is a bit more than educated guess:

Are you talking about this Wifibroadcast , here?

If so: well yes, monitor mode is the underlying technology, as can be seen here.

Now, if this is about doing a commercial product, sadly, you cannot expect any kind of interoperability from this.

Streaming audio/video over Wi-Fi is a business, and the the power in charge (Wi-Fi Alliance aka WFA) as some view on it, including certification programs. Have a look at Miracast, using Wi-Fi Direct.

As for multicast / broadcast, it is even more of a business and the realm of proprietary technologies for now (example here – and no, this is not limited to automobile). This is quite complicated, to start with because of the synchronization problem across receivers: you don’t want 2 radio receivers in the same room to play with a 1 seconds delay, this would be cacophony.


Meaning, be it with the Wifibroadcast OSS project or with the proprietary industry about it, since there is not yet an open protocol for this (as “publicly available standard specification”, I don’t even go about implementation, FLOSS or not), you will have to provide a specific application for every receiver to match your broadcaster protocol, and vice versa. And that is the state of the industry today. That is what the company I mentioned above, or this other one more well know, or these are doing. And so, they do not interoperate. This will be your problem: provide a receiver app for Windows, Mac OS, Android and iOS (where you may not even have access to sub-layer 3 API) that will match your radio broadcaster protocol. And Linux too, please.

Though, this is the direction of history because this is what the user wants: stream A/V to/from device/application X from brand A to device/application Y from brand B.

And so people have been working on this, on layer 2, because layer 3 and above have unsolvable challenges with it, at IEEE since 2004 with Ethernet AVB, which is a set of protocols. You can download some of its standards for free, others for a moderate fee depending on how old they are. There is a SIG taking care of certification(http://avnu.org/certified-products/) to guarantee interoperability.

It is for 802.3 (aka wired Ethernet), but there is some work done to bring this to 802.11 Wi-Fi. Because again, that’s what the user wants, the market is here, no question about that. It will take a long time. Even more to get consumer electronic grade devices or applications of the shelves. But they will interoperate out of the box, that’s the goal.

There’s even been work done on moving this to layer 3/IP as well BTW, with some performance sacrifice.

So come back in a few years, and all should be setup. Or, if you have lots of time and money and no urge to deliver, implement a solution based on these standards?


Link to AVnu (Ethernet AVB SIG) page about use cases for consumer electronics audio streaming, wired or wireless:


…and its 10 pages white paper at the bottom of the page.


Because terminology is important in engineering, because one can easily get drowned by acronyms when delving in a new tech area, and because I cannot read (even less use) an acronym without knowing what it stands for, I developed a tendency to collect tech terms – a bit like some do collecting stamps.

I started this jargon file circa the end of 2012, when digging into Ethernet AVB (now renamed TSN), so this list is heavily geared towards layer 2 networking technology, as well as automotive since this is my application domain.

I plan / hope to feed this list with other techs as well – actually, I just found two other “jargon files” in my Dropbox: one for Wi-Fi, and a small one with bits of audio stuff.


  • 1PoDL Ethernet 1-Pair Power over Data Lines, IEEE 802.3bu
  • 1TPCE 1 Twisted Pair 100 Mbit/s Ethernet, IEEE standard version of Broadcom’s BroadR’Reach
  • 5C 5 criteria (IEEE) 1/ broad market potential 2/ compatibility 3/ distinct identity 4/ technical feasibility 5/ economic feasibility


  • AAA2C AVnu sponsored Automotive AVB Gen 2 Council (aka AVB for automotive)
  • AABAC AVnu Alliance Broadcast Advisory Council (AVB for TV industry)
  • AAF AVTP Audio Format [AVTPa]
  • ABNF Augmented BNF as defined by RFC 5234
  • ACF Automotive Control Format (IEEE P1722a)
  • ACL Access Control List
  • ACM Association for Computing Machinery
  • ACMP AVDECC Connection Management Protocol
  • ACMPDU AVDECC Connection Management Protocol Data Unit
  • ADAS Advanced Driver Assistance Systems
  • ADASIS forum, Advanced Driver Assistance Systems Interface Specification forum
  • ADDTS Add Traffic Stream (Wi-Fi 802.11e)
  • ADEV Allan Deviation (802.1AS)
  • ADP AVDECC Discovery Protocol
  • ADPDU AVDECC Discovery Protocol Data Unit
  • ADU application data units
  • AEC Automotive Electronics Council
  • AECP AVDECC Enumeration and Control Protocol
  • AECPDU AVDECC Enumeration and Control Protocol Data Unit
  • AECQ 100 Automotive Electronics Council critical stress test qualification for automotive integrated circuits
  • AED Automotive Ethernet Device. An automotive device with Ethernet AVB functionality.
  • AED-A Automotive Ethernet Audio Device. An AED that provides support for transmission and/or receipt of uncompressed audio over an Ethernet AVB network.
  • AED-B Automotive Ethernet Bridge Device.
  • AED-C Automotive Ethernet Clock Device. An AED that provides support for transmission and/or receipt of a media clock reference over an Ethernet AVB network.
  • AED-E Automotive Ethernet Endpoint Device
  • AED-GM Automotive Ethernet Grand Master
  • AED-V Automotive Ethernet Video Device. An AED that provides support for transmission and/or receipt of compressed video over an Ethernet AVB network.
  • AEL Automotive Ethernet Listener.
  • AEM AVDECC Entity Model
  • AES3 aka AES/EBU standard for the exchange of digital audio signals betweenprofessional audio devices, see also S/PDIF
  • AET Automotive Ethernet Talker.
  • AFDX Avionics Full-Duplex Switched Ethernet, a data network for safety-critical applications that utilizes dedicated bandwidth while providing deterministic Quality of Service (Airbus)
  • ALF Application Level Framing (IETF, Clark and D. Tennenhouse, “Architectural Considerations for a New Generation of Network Protocols”)
  • AP Access Point (Wi-Fi)
  • APC AVDECC Proxy Client
  • APP AVDECC Proxy Protocol
  • APS AVDECC Proxy Server
  • AQM In Internet routers, active queue management is a technique that consists in dropping or ECN-marking packets before a router’s queue is full.
  • ASI AudioScience, Inc. (company)
  • ASIL Automotive Safety Integrity Level
  • ATIS Alliance for Telecommunications Industry Solutions (SDO)
  • ATU XXX? Marvell swcfg “Add ethernet address of the given enet interface to the switch ATU”, “ATU table access”
  • automotive domains: Powertrain (engine, transmission), chassis (steering, ABS, tire pressure), body (doors, lamps, seats, A/C), safety (air-bags, sensors, actuators, occupant safety system). Infotainment and driver assist have not been considered as domains until recently.
  • AUTOSAR AUTomotive Open System ARchitecture
  • AVB Audio Video Bridging, “provide the specifications that will allow time-synchronized low latency streaming services through IEEE 802 networks”
  • AVDECC AV Device discovery, Enumeration, Connection management and Control protocol (IEEE P1722.1)
  • AVR Audio Video Recorder (consumer electronic)
  • AVTP AVB Transport Protocol aka IEEE 1722
  • AWM Audio With Metadata (IEEE P1722a)


  • B-MAC Backbone MAC
  • B-VID Backbone VLAN ID
  • B-VLAN Backbone VLAN
  • BC boundary clock (802.1AS)
  • BCB Backbone Core Bridge
  • BDP bandwidth-delay product, the product of a data link’s capacity (in bits per second) and its end-to-end delay (in seconds).
  • BEB Backbone Edge bridge
  • BER Bit Error Rate
  • BLCE Bridge Local Computation Engine (IEEE)
  • BLS Burst limiting Shapper
  • BMC Best Master Clock, IEEE 1588
  • BMCA Best Master Clock Algorithm, IEEE 1588
  • BNF Backus-Naur Form
  • BOG IEEE-SA Board Of Governors (IEEE)
  • BPDU Bridge Protocol Data Units, intervient dans le spanning tree protocol (STP)
  • BRR (Broadcom) Ethernet BroadR-Reach® aka UTP aka OABR aka BR
  • BSC Broadcom Serial Control
  • BoD Board of Director (AVnu)
  • bT bit-times (AVnu certification tests)
  • BroadSync HD, brand, commercial name of Broadcom’s custom implementation of AVB


  • C&C Command & Control
  • C&I Commercial & Industrial
  • C&I Conformance and Interoperability
  • C-ITS Cooperative Intelligent Transport Systems (see ITS)
  • C-MAC Customer MAC Address (IEEE)
  • C-TAG Customer TAG
  • C-VID Customer VLAN ID
  • C-VLAN Customer VLAN (IEEE Std 802.1Q)
  • C2C Car To Car communication
  • C2I Car To Infrastucture Communication
  • C2X Car To X = C2C + C2I
  • CAG Corporate Advisory Group (IEEE)
  • CAGR Compound Annual Growth Rate (business)
  • CALM Communications Access for Land Mobiles (ISO TC 204/Working Group 16)
  • CAM Table Content addressable memory table, or MAC table (Ethernet)
  • CAN Controller Area Network
  • CAN FD CAN Flexible Data-Rate: an extension of the CAN specification which allows for data rates higher than 1 MBit/s and payloads longer than 8 octets per frame. See CAN with Flexible Data-Rate, White Paper Version 1.1 from Bosch Semiconductors for more information
  • CBP Customer Backbone Port (IEEE)
  • CBQ Class Based Queueing (traffic control)
  • CBS Credit-Based Shaper
  • CCC Car Connectivity Consortium
  • CCF Congestion Controlled Flow (IEEE)
  • CCM Connectivity/Continuity Check Message (IEEE CFM)
  • CDCP Channel Discovery and Configuration Protocol (IEEE 802.1Qbg)
  • CDS Certification Development Subgroup (AVnu)
  • CDT Control Data Traffic
  • CE4A Consumer Electronics for Automotive SIG
  • CEDIA Custom Electronic Design & Installation Association (SIG)
  • CEO’s best effort see Excellent Effort (IEEE)
  • CESD Cable-Sourced Electrostatic Discharge
  • CFD Control Format Descriptor
  • CFI Call For Interest (IEEE process)
  • CFI canonical format indicator
  • CFM Connectivity Fault Management (IEEE)
  • CFP C Form-factor Pluggable (40 and 100 Gigabit Ethernet)
  • CFP Call For Paper (conference process)
  • CFP Call for Participation (IEEE)
  • CFP Compact Field Processor (Broadcom)
  • CIP common isochronous packet
  • CIST Colloquium in Information Science and Technology (IEEE)
  • CIST Common and Internal Spanning Tree (IEEE 802.1)
  • CM Clock Master
  • CN-TAG Congestion Notification Tag (IEEE)
  • CNAME canonical name (RTP)
  • CND Congestion Notification Domain (IEEE)
  • CNM Congestion Notification Message (IEEE)
  • CNPV Congestion Notification Priority Value (IEEE)
  • COE Checksum Offload Engine
  • CP Congestion Point (IEEE)
  • CPM Certification Logo Program Manager (AVnu)
  • CPS cyber-physical system (IoT)
  • CPTS Common Platform Time Stamp (Texas Instruments Linux)
  • CR Constrained Routing
  • CRF Clock Reference Format (IEEE P1722a)
  • CS Clock Slave
  • CSMA/CA Carrier Sense Multiple Access with Collision Avoidance (ex Wi-Fi)
  • CSMA/CD Carrier Sense Multiple Access / Collision Detection (ex Ethernet)
  • CSN Coordinated Shared Networks
  • CSRC contributing source (IEEE 1733)
  • CST Common Spanning Tree (IEEE)
  • CTC Channel Time Clock
  • CTG Common Timing Grid, IEEE P1722a
  • CVBS analog Color Video Blanking Signal, utilise par les cameras
  • CoS Class of Service, IEEE 802.1p (802.1A) (IETF)


  • DA Destination MAC Address
  • DAB Digital Audio Broadcasting
  • DBC data block count
  • DBS data block size
  • DCB Data Center Bridging, a sub-group from IEEE 802
  • DCBX Data Center Bridging eXchange
  • DCCP Datagram Congestion Control Protocol (RFC 4340, RFC 4336)
  • DCN Data Center Network
  • DCP Digital Content Protection LLC (HDCP SIG)
  • DDCFM data-driven and data-dependent connectivity fault management (IEEE)
  • DDF data-driven and data-dependent fault (IEEE)
  • DECC device Discovery, Enumeration, Connection management and Control
  • DEI Drop Eligible Indicator
  • DFE Decision Feedback Equalization (IEEE 802.3)
  • DLPI Data Link Provider Interface, an interface that a network device driver implements. It corresponds to the Data Link Layer (aka layer 2).
  • DLS Direct Link Setup (Wi-Fi STA-STA, 802.11)
  • DMN Designated MSRP Node (IEEE)
  • DMP Digital Media Player
  • DMS Digital Media Server
  • DON Decoding Order Number (RTP H.264)
  • DONB Decoding Order Number Base (RTP H.264)
  • DOND Decoding Order Number Difference (RTP H.264)
  • EPD EtherType Protocol Discrimination
  • DR Decapsulator Responder (IEEE)
  • DR designated representative (IEEE)
  • DRA designated representative alternate (IEEE)
  • DRM digital rights management
  • DRNI Distributed Resilient Network Interconnect (IEEE, not AVB)
  • DRR Distributed Round Robin(scheduling)
  • DSA Marvell, Distributed Switch Architecture, a protocol for managing hardware switch chips
  • DSCP Differentiated Services Code Point (QoS IETF)
  • DSDT ?? Marvell switch – Distributed Switch Driver Technology?
  • DSRC Dedicated Short Range Communications
  • DSoNets Dynamic Social Networks
  • DTCP Digital Transmission Content Protection, see also DTLA (DRM, (www.dctp.org)
  • DTLA Digital Transmission Licensing Administrator, see also DTCP
  • DVCR digital videocassette recorder
  • DVI Digital visual interface
  • DVMRP Distance Vector Multicast Routing Protocol (IP)
  • DWRR Deficit Weighted Round Robin
  • DiffServ Differentiated Services (IETF)
  • DoIP Diagnostics over Internet Protocol, ISO 13400
  • DoSAP Domain Service Access Point (IEEE)


  • E-LAN Ethernet LAN (multipoint) service
  • E-LINE Ethernet Line (point-to-point) service
  • E-LMI Ethernet Local Management Interface (Metro Ethernet Forum)
  • E-TREE Ethernet Tree (rooted multipoint) service
  • E2E TC End to End Transparent Clock (IEEE 1588)
  • EAP Extensible Authentication Protocol
  • EAPS Ethernet Automatic Protection Switching (proprietary, Extreme Networks)
  • EAV End of Active Video, byte sequence defined by ITU-R BT.656
  • EB Edge Bridge
  • EBU European Broadcasting Union
  • EC (IEEE) Executive Comitee
  • ECC Elliptic curve cryptography
  • ECMP Equal Cost Multiple Path (IEEE P802.1Qbp, amendment to VLAN)
  • ECN Engineering Change Notice (process)
  • ECN Explicit Congestion Notification (2001)
  • ECR Efficient Consumer Response?
  • EDCA Enhanced Distributed Channel Access (Wi-Fi QoS 802.11e)
  • EDCA-AC Enhanced Distributed Channel Access – Access Categories (802.11)
  • EDCF Enhanced Distributed Coordination Function (Wi-Fi QoS)
  • EF Expedited Forwarding (IETF)
  • EFM Ethernet in the First Mile, aka ETTH Ethernet to the Home (IT)
  • EISS Extended Internal Sublayer Service (IEEE Std 802.1Q)
  • EISS-SAP EISS Service Access Point (IEEE)
  • eMAC express MAC (802.1Qbu, frame preemption)
  • EMC ElectroMagnetic Compatibility
  • EMI ElectroMagnetic Interference
  • EPD EtherType Protocol Discrimination
  • EPON Ethernet Passive Optical Network
  • ESP Ethernet Switched Path (IEEE)
  • ESS extended service set
  • ETS Enhanced Transmission Selection (IEEE 802.1Qaz)
  • ETTH Ethernet to the Home, aka EFM Ethernet in the First Mile
  • EUI IEEE Extended Unique Identifier
  • EUI-48 Extended Unique Identifier (IEEE), 48 bit MAC address “the distinction between EUI-48 and MAC-48 identifiers is purely nominal: MAC-48 is used for network hardware; EUI-48 is used to identify other devices and software.”
  • EV Electric Vehicles
  • EVB Edge Virtual Bridging (IEEE 802.1Qbg)
  • Excellent Effort or “CEO’s best effort”, the best-effort type services that an information services organization would deliver to its most important customers (IEEE)


  • FCS Frame Check Sequence
  • FD Full-Duplex
  • FDB Forwarding (or Filtering?) Data Base (switch layer 2)
  • FDDI Fiber Distributed Data Interface
  • FDF format dependent field
  • FEC Forward Error Correction (RTP H.264)
  • FID Filtering Identifier (VLAN)
  • FIPS Federal Information Processing Standards (itl.nist.gov/fipspubs)
  • FLP Fast Link Pulse (autonegotiation)
  • FMT stream format
  • FOTA Firmware Over-The-Air
  • FP Fixed Priority (scheduling)
  • FPT forward path test (IEEE)
  • FQTSS Forwarding and Queuing for Time-Sensitive Streams, IEEE 802.1Qav
  • FR Forwarding Rate (RFC 2889)
  • FRMOL Forwarding Rate at Maximum Offered Load (RFC 2889)
  • FRR Fast Re-Route
  • FTP Foiled Twisted Pair
  • FU Fragmentation Units (H.264)
  • Firewire see IEEE 1394, IEC 61883
  • FttDP Fiber to the Distribution Point (fibre optique)


  • GARP Generic Attribution Registration Protocol, replaced by MRP
  • GASP global asynchronous stream packet
  • GCM Galois/Counter Mode, exemple AES-GCM
  • GENA General Event Notification Architecture (Microsoft crap)
  • glass to glass latency, from camera lens to display
  • GM grandmaster
  • GMT Greenwich mean time
  • GPON Gigabit Passive Optical Network
  • gPTP Generalized Precision Time Protocol (IEEE 802.1AS)
  • GRE Generic Routing Encapsulation
  • GSO generic segmentation offload
  • GUID Globally Unique IDentifier
  • GVRP GARP VLAN Registration Protocol or Generic VLAN Registration Protocol


  • HANC Horizontal Ancillary Data
  • HBM Himan Body Model (for electrical shock)
  • HCCA HCF Controlled Channel Access (802.11)
  • HCF Hybrid Coordination Function (802.11)
  • HD Half-Duplex
  • HDCP High-Bandwidth Digital Content Protection (DRM, HDMI)
  • HDCP IIA HDCP (High-bandwidth Digital Content Protection) IIA (Interface Independent Adaptation)
  • HDMI High-Definition Multimedia Interface
  • HEV Hybrid Electric Vehicles
  • HFSC Hierarchical Fair Service Curve (traffic control)
  • HRM hypothetical reference model (IEEE)
  • HSR High-availability Seamless Redundancy (IEC 62439-3)
  • HSRP Hot Standby Router Protocol (Cisco, RFC 2281)
  • HTB Hierarchy Token Bucket (traffic control)


  • I-SID Backbone Service Instance Identifier
  • I-tag Backbone Service Instance TAG
  • IAM Intelligent Antenna Module, with Ethernet as a remplacement for expensive coax cable
  • IBoE Infiniband over Ethernet
  • ICT Information and Communications Technology
  • IDR Instantaneous Decoding Refresh (RTP H.264)
  • IEC International Electrotechnical Commission
  • IEC 61883 Consumer audio/video equipment – Digital interface is a technical standard for a digital interface that is used by IEEE 1394 (FireWire) devices for audio and video equipment, see IEEE 1394, aka Firewire
  • IEC 61883-4 MPEG2-TS data transmission
  • IEC 61883-6 Audio and music data transmission protocol
  • IEC International Electrotechnical Commission (www.iec.ch)
  • IEEE 1394 Firewire (IEC 61883, IEEE 1722)
  • IEEE 1588 Precision Time Protocol (PTP), synchronise distributed clocks with an accuracy of less than 1 microsecond via Ethernet networks, designed to fill a niche not well served by either of the two dominant protocols, NTP and GPS
  • IEEE 1609 Dedicated Short Range Communication (for WAVE) (V2V, V2I)
  • IEEE 1722 Layer 2 Transport Protocol for Time-Sensitive Applications in Bridged Local Area Networks aka AVB Transport Protocol aka AVBTP aka AVTP, defines encapsulations for a variety of media formats and associated synchronization mechanisms, by “by leveraging concepts of IEC 61883-1 through IEC 61883-8 (FireWire)”
  • IEEE 1722.1 device Discovery, Enumeration, Connection management & Control protocol for AVTP devices, aka AVDECC
  • IEEE 1733 Layer 3 Transport Protocol for Time-Sensitive Applications in Local Area Networks
  • IEEE 802.11aa-2012 MAC Enhancements for Robust Audio Video Streaming, cl. 6 Reservations (ADDTSRESERVE, Higher Layer Stream ID)
  • IEEE 802.11ac-2013 5 GHz band
  • IEEE 802.11ad-2012 Wireless Gigabit aka WiGig
  • IEEE 802.11ah ultra-low power version of Wi-Fi, 1GHz, for home automation, under development (2014)
  • IEEE 802.11ak Enhancements For Transit Links Within Bridged Networks, see also 802.1Qbz/GLK General Link project
  • IEEE 802.11e-2005 MAC Quality of Service Enhancements
  • IEEE 802.11p Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications Amendment 6: Wireless Access in Vehicular Environments (V2V, V2I)
  • IEEE 802.11p wireless access in vehicular environments (WAVE), data exchange between high-speed vehicles and between the vehicles and the roadside infrastructure
  • IEEE 802.11s WLAN Mesh Networking
  • IEEE 802.11v-2011 wireless network management, with cl. 10 Timing Measurement (802.11-2012, cl. 6)
  • IEEE 802.1AE aka MACSec or MAC Security, provides connectionless user data confidentiality, frame data integrity, and data origin authenticity (802.1AE-2006)
  • IEEE 802.1AR Secure Device Identity, DevID
  • IEEE 802.1AS Timing and Synchronization, full title “Standard for Local and Metropolitan Area Networks – Timing and Synchronization for Time-Sensitive Applications in Bridged Local Area Networks”. IEEE 802.1AS-2011 is part of the IEEE Audio Video Bridging (AVB) group of standards. It specifies a profile for use of IEEE 1588-2008 for time synchronization over a virtual bridged local area network (as defined by IEEE 802.1Q). In particular, 802.1AS defines how IEEE 802.3 (Ethernet), IEEE 802.11 (Wi-Fi), and coordinated shared networks like MoCA (Multimedia over Coax Alliance) can all be parts of the same timing domain.
  • IEEE 802.1ASbt Timing and Synchronization: Enhancements and Performance Improvements (TSN)
  • IEEE 802.1AX Link Agregation
  • IEEE 802.1BA Audio Video Bridging Systems
  • IEEE 802.1D MAC Bridges, 802.1D-2004
  • IEEE 802.1Qa Stream Reservation Protocol aka SRP
  • IEEE 802.1Qau Congestion Notification (TSN) (incorporated into 802.1Q-2011)
  • IEEE 802.1Qav Forwarding and Queuing for Time-Sensitive Streams aka FQTSS
  • IEEE 802.1Qaz Enhanced Transmission Selection (TSN) (published 802.1Qaz-2011)
  • IEEE 802.1Qbb Priority-based Flow Control (TSN) (published 802.1Qbb-2011)
  • IEEE 802.1Qbg Edge Virtual Bridging (TSN) (published 802.1Qbg-2012)
  • IEEE 802.1Qbp ECMP (Equal Cost Multiple Paths)
  • IEEE 802.1Qbu Frame Preemption (TSN)
  • IEEE 802.1Qbv Enhancements for Scheduled Traffic (TSN)
  • IEEE 802.1Qbz Enhancements to Bridging of 802.11 Media
  • IEEE 802.1Qca Path Control and Reservation (flow management)
  • IEEE 802.1Qcb Frame Replication and Elimination for Reliability (flow management)
  • IEEE 802.1Qcc Stream Reservation Protocol (SRP) Enhancements and Performance Improvements (TSN)
  • IEEE 802.1Qch Cyclic Queuing and Forwarding
  • IEEE 802.1X “EAP over LAN” or EAPOL, Port Based Network Access Control (IEEE 802.1X-2010)
  • IEEE 802.1p QoS, incorporated into IEEE 802.1D-1998
  • IEEE 802.3 aka Ethernet, “physical layer and data link layer’s media access control (MAC) of wired Ethernet”
  • IEEE 802.3ad Link Aggregation Control Protocol (LACP), called ‘Etherchannel’ by Cisco, ‘trunking’ by Sun, and ‘bonding’ by Linux, superseded: moved to IEEE 802.1AX
  • IEEE 802.3af-2003 Power over Ethernet (PoE) 12.95 W ( IEEE 802.3af-2003), superseded by IEEE 802.3at
  • IEEE 802.3at PoE+, PoE plus, 600 mA, 25.5W, 2009
  • IEEE 802.3bd MAC Control Frame for Priority-based Flow Control (TSN) (802.3bd-2011, superseded)
  • IEEE 802.3bp RTPGE Reduced Twisted Pair Gigabit Ethernet
  • IEEE Institute of Electrical and Electronics Engineers
  • IEEE P1722a – IEEE Standard for “Layer 2 Transport Protocol for Time Sensitive Applications in a Bridged Local Area Network Amendment 1 – Extensible Streaming Formats”, en clair faire passer autre chose que de l’audio/video sur l’Ethernet AVB. En cours. Amendement au IEEE 1722-2011. Initie 26/07/2011. D’apres le draft 2 (mars 2012): CAN Base, CAN Extended, FlexRay, LIN. Chair Dave Olsen (Harman), Vice-chair Matthew Xavier Mora (Apple, Manager Audio Software), editeur Jeff Koftinoff (Meyer Sound), Helge Zinner (Continental) http://grouper.ieee.org/groups/1722/ http://standards.ieee.org/develop/project/1722a.html
  • IEEE P802.11ak Enhancements For Transit Links Within Bridged Networks
  • IEEE P802.1CB Frame Replication and Elimination for Reliability (see also IETF PCE)
  • IEEE P802.1Qbp VLAN amendment: ECMP Equal Cost Multiple Path
  • IEEE P802.1Qca Path Control and Reservation (see also IETF ISIS and PCE)
  • IEEE P802.1Qcc Stream Reservation Protocol Enhancements and Performance Improvements (see also IETF PCE)
  • IEEE P802.3br Interspersed Express Traffic (IET) (IEEE) Broadcom, Siemens
  • IEEE 802.3bu 1-Pair Power over Data Lines (1PoDL)
  • IEEE 802.3bv 1000 Mb/s Operation Over Plastic Optical Fiber (goal = replacement for MOST)
  • IEEE 802.3bw 100 Mb/s Operation over a Single Balanced Twisted Pair Cable aka 100BASE-T1 (standard, non-proprietary version of Broadcom’s BroadR-Reach)
  • IESG Internet Engineering Steering Group (IETF)
  • IET Interspersed Express Traffic (traffic shaping), see IEEE P802.3br
  • IETF Internet Engineering Task Force
  • IFG Inter Frame Gap = interframe spacing = IPG = InterPacket Gap = minimum idle time to respect between frame transmission. Minimum 96 bits time.
  • IGMP Internet Group Management Protocol (multicast routing)
  • IIDC Instrumentation & Industrial Digital Camera (IEC 61883, IEEE 1394, IEEE 1722)
  • IMB Inband Management Port (Broadcom)
  • IoE Internet of Everything
  • IPF Ingress Policing Filter
  • IPG inter packet gap, see IFG
  • IPR INtellectual Property Rights
  • IPS Infrastructure Protection Switching
  • IS-IS Intermediate System to Intermediate System (IETF RFC 1142)
  • ISAP Intermediate Service Access Points (IEEE)
  • ISIS IS-IS for IP Internets (IETF WG, with liaison to IEEE P802.1Qca)
  • ISO International Organization for Standardization
  • ISO 17215 – VCIC, Video communication interface for cameras (ADAS)
  • ISO 17215-1:2014 Road vehicles – Video communication interface for cameras (VCIC) – Part 1: General information and use case definition
  • ISO 17386 recommendation for parking aid systems to establish a video link 350 ms
  • ISO 17386:2010 Transport information and control systems – Manoeuvring Aids for Low Speed Operation (MALSO) – Performance requirements and test procedures
  • ISS Internal Sublayer Service (IEEE)
  • ISS-SAP ISS Service Access Point (IEEE)
  • IST Internal Spanning Tree (IEEE)
  • ITS Intelligent Transport Systems, de ETSI (European Telecommunications Standards Institute) ITS, telematics and all types of communications in vehicles, between vehicles (e.g. car-to-car), and between vehicles and fixed locations (e.g. car-to-infrastructure).
  • ITU International Telecommunication Union
  • ITU-T ITU Telecommunication Standardization Sector
  • ITU-T Y.1564 Ethernet service activation test methodology (2011)
  • IVL Independent Virtual Local Area Network (VLAN) Learning (IEEE)
  • IVN In-Vehicule Networking (LIN CAN FlexRay MOST Ethernet…)
  • IWK Interworking, a sub-group from IEEE 802
  • Infotainment & Driver Assist: Navigation, Telematics, TV/Radio/CD/DVD, RSE, Cameras
  • IntServ Integrated Services (IETF)


  • jabber frame an Ethernet frame longer than 1518 bytes (IEEE) see also runt frame
  • jabber: the term “jabber” is also used in the Institute of Electrical and Electronic Engineers (IEEE) 802.3 specification for any frame of data that exceeds the maximum frame length for that specification. For Ethernet networks, the maximum frame length is 1518 bytes (18 bytes of overhead and 1500 bytes of payload). A frame longer than 1518 bytes is often called a “jabber frame.” Another name for jabbering is “longpacket error.”
  • JASPAR Japan Automotive Software Platform and Architecture
  • Jumbo Frame/Jumbo Packet = more than 1500 bytes. Synopsys Ethernet IP: jusqu’a 16 kB


  • KPI key performance indicator


  • LACP Link Aggregation Control Protocol (802.3ad)
  • LAG Link Agregation Group (802.3ad)
  • LAN Local Area Network
  • LBM Loopback Message (IEEE)
  • LBR Loopback Reply (IEEE)
  • LCW Link Code Word (autonegotiation)
  • LFA Loop Free Alternates
  • LFN long fat network (often pronounced “elephant”). As defined in RFC 1072, a network is considered an LFN if its BDP is significantly larger than 105 bits (12500 bytes).
  • LIN Local Interconnected Network
  • LIT Link Integrity Test (autonegotiation)
  • LLDP Link Layer Discovery Protocol (IEEE 802.1Qbg), related to IEEE 802.1AB “Station and Media Access Control Connectivity Discovery”
  • LMI Layer Management Interface (IEEE, OSI)
  • LMSC LAN/MAN Standards Committee (IEEE)
  • LOA Letter of Assurance (IEEE, patents)
  • LOM Linktrace Output Multiplexer (IEEE)
  • LPD LLC Protocol Discrimination
  • LPI Low Power Idle
  • LR Listener Ready (AVB)
  • LRO Large receive offload
  • LSB Least significant byte
  • LSO large segment offload
  • LTM Linktrace Message (IEEE)
  • LTR Linktrace Reply (IEEE)
  • LVDS digital Low Voltage Differential Signaling, utilise par les cameras
  • lwIP, LWIP open source lightweight TCP/IP stack


  • MA Maintenance Association (IEEE CFM)
  • MAAP MAC address acquisition protocol (AVB IEEE 1722)
  • MAAP Multicast Address Allocation Protocol (AVB IEEE 1722)
  • MAC Media Access Control
  • MAC table see CAM table (Ethernet)
  • MAC-in-MAC used for PBB
  • MACSec, MAC Security, see IEEE 802.1AE
  • MAD MRP Attribute Declaration
  • MAID Maintenance Association Identifier (IEEE)
  • MALLOC IETF Working Group, Multicast-Address Allocation
  • MALSO Manoeuvring Aids for Low Speed Operation
  • MAN Metro Area Network
  • MANE Media-Aware Network Element (RTP H.264)
  • MAP MRP Attribute Propagation
  • MCS Media Clock Stream
  • MD Level Maintenance Domain Level (IEEE CFM)
  • MD Media-Dependent (IEEE)
  • MDC Management Data Clock (Ethernet PHY)
  • MDIO Management Data Input/Output, aka SMI, used to transfer management information between MAC and PHY.
  • MDIX medium-dependent interface crossover (ex auto-MDIX, port will automatically detect the Ethernet cable type being used, straight-through or crossover) (deprecated, more for hub than switch
  • MDSP Multi Domain Segmented Network Protection (ITU, not AVB)
  • ME Maintenance Entity (IEEE)
  • MEF Metro Ethernet Forum
  • MEP Maintenance association End Point (IEEE)
  • MEPID Maintenance association End Point Identifier (IEEE)
  • MEXT Mobility EXTensions for IPv6 (IETF, concluded working group)
  • MFR Maximum Forwarding Rate (RFC 2889)
  • MHF MIP Half Function (IEEE)
  • MHL Mobile High-Definition Link
  • MIB Management Information Base, defined using a subset of Abstract Syntax Notation One (ASN.1) called “Structure of Management Information Version 2 (SMIv2)” RFC 2578. IEEE, IETF.
  • MIDI Musical Instrument Digital Interface
  • MII Media Independent Interface
  • MIIM Media Independent Interface Management (Ethernet PHY)
  • MIMSTR Media-Independent MaSTeR (AVnu, UNH-IOL)
  • MIP Maintenance domain Intermediate Point (IEEE)
  • MIPI Mobile Industry Processor Interface Alliance (SIG)
  • MKA MAC security Key Agreement protocol (IEEE)
  • MLME MAC Layer Management Entity
  • MMA Musical Instrument Digital Interface (MIDI) Manufacturers Association
  • MMP Marvell Media Processor
  • MMRP Multiple MAC Registration Protocol
  • MMRP Multiple Multicast Registration Protocol
  • MOL Maximum Offered Load (RFC 2889)
  • MOST Media Oriented Systems Transport
  • MP Maintenance Point (IEEE CFM)
  • MPDU MAC Protocol Data Unit aggregation
  • MPEG Moving Pictures Expert Group
  • MPLS Multiprotocol Label Switching (IETF)
  • MRD Market requirements document
  • MRL Maximum Relative Latency
  • MRP Multiple Registration Protocol, IEEE 802.1ak-2007 (superseded, included in IEEE 802.1A)
  • MSA Multi-Source Agreement (business)
  • MSB Most significant byte
  • msb Most significant bit
  • MSC Message Sequence Chart
  • MSDU MAC Service Data Unit aggregation
  • MSP MAC Status Propagation (IEEE 802.1)
  • MSP MAC Status Protocol (IEEE 802.1)
  • MSRP Multiple Stream Registration Protocol (IEEE)
  • MSRPDU Multiple Stream Registration Protocol Data Unit
  • MST BPDU Multiple Spanning Tree Bridge Protocol Data Unit (IEEE)
  • MST Multiple Spanning Tree (IEEE)
  • MSTI Multiple Spanning Tree Instance (IEEE)
  • MSTP Multiple Spanning Tree Algorithm and Protocol (IEEE)
  • MTAP Multi-Time Aggregation Packet (RTP H.264)
  • MTAP16 MTAP with 16-bit timestamp offset (RTP H.264)
  • MTAP24 MTAP with 24-bit timestamp offset (RTP H.264)
  • MTIE Maximum Time Interval Error
  • MTL MAC Transaction Layer
  • MTT Maximum Transit Time
  • MTTFPA Mean Time to False Packet Acceptance
  • MTU Maximum Transfer Unit as described by RFC 791
  • MVRP Multiple VLAN Registration protocol
  • MWG Marketing Work Group (AVnu SIG)
  • M&M’s “Marvell + Micrel” according to car makers
  • MoCA Multimedia over Coax Alliance
  • MOSTCO MOST cooperation (SIG)
  • MTG Marketing Task Group (Wi-Fi Alliance)


  • NAK Negative Acknowledgment
  • NAL Network Abstraction Layer (H.264)
  • NALU Network Abstraction Layer Units (H.264)
  • NBMA Non-Broadcast Multiple Access network (typically :ATM, Frame Relay, X.25, and home power line networking)
  • NCF NAK Confirmation
  • NDP Neighbour Discovery Protocol
  • NEMO Network Mobility (IETF RFC 3963)
  • NesCom New Standards Committee (IEEE)
  • NETCONF Network Configuration Protocol (IETF RFC 6241, may replace SNMP at IEEE)
  • NHTSA National Highway Traffic Safety Administration (USA)
  • NIC network interface card
  • NLP Normal Link Pulses (autonegotiation)
  • NM (automotive) Network Management. Automotive: solely used to keep ECUs awake or control their energy consumption.
  • NTP Network Time Protocol (IETF RFC 1305)
  • NVGRE Network Virtualization using Generic Routing Encapsulation


  • OABR OPEN Alliance BroadR-Reach
  • OAM Operations, Administrative and Maintenance functions (IEEE) (ITU-T Recommendation Y.1731)
  • OBD On Board Diagnostics (automotive)
  • OBE On-board-Equipment
  • OC Ordinary Clock (IEEE 1588 and 802.1AS)
  • OccupiedFS occupied Ethernet frame size on the wire, ex 1542 bytes for a 1500 bytes payload (AVnu certification tests)
  • OLT Optical Line Terminal (802.3)
  • ONF Open Networking Foundation
  • ONU Optical Network Unit (802.3)
  • OSPFv2 Open Shortest Path First, RFC2328


  • P&P Policies & Procedures (IEEE)
  • P2P TC Peer to Peer Transparent Clock (IEEE 1588)
  • PAF PME Aggregation Function (Ethernet IEEE 802.3 clause 61)
  • PAR Project Authorization Request, IEEE process
  • partitioning: partial network operation based on power over ethernet PoE aka IEEE 802.3af
  • PB Provider Bridge
  • PBB Provider Backbone Bridge (IEEE)
  • PBB-TE Provider Backbone Bridge – Traffic Engineering (IEEE)
  • PBBN Provider Backbone Bridged Network (IEEE)
  • PCE Path Computation Element (IETF WG, with liaison to IEEE P802.1CB, P802.1Qca, P802.1Qcc)
  • PCI Protocol Control Information, model OSI
  • PCP Priotity Code Point of a VLAN, IEEE 802.1p (802.1A)
  • PCR Path Control and Reservation
  • PCS Physical Coding Sublayer (Ethernet)
  • PCS Profile Conformance Statement (IEEE)
  • PDELAY Peer Delay (AVB)
  • PDU Protocol Data Unit, modele OSI
  • PE Provider Edge
  • PES Packetized Elementary Stream (MPEG-2)
  • PFC Priority-based Flow Control (ou Programmable Flow Control)
  • PHC PTP Hardware Clock (Linux)
  • PHEV Plug-in Hybrid Electric Vehicles
  • PICS Protocol Implementation Conformance Statement (IEEE)
  • PIP Provider Instance Port (IEEE)
  • PIRL Port Based Ingress Rate Limiting (Marvell)
  • PLR Point of Local Repair
  • PMA Physical Medium Attachment.
  • PME Physical Medium Entities (Ethernet)
  • pMAC preemptable MAC (802.1Qbu, frame preemption)
  • PPAP Production Part Approval Process (automotive industrialization)
  • PPS Pulse Per Second (Linux), a special pulse provided by some GPS antennae. Userland can use it to get a high-precision time reference. Used by Linux for PTP.
  • pps packets per second
  • PRP Parallel Redundancy Protocol (IEC 62439-3)
  • PS Peristaltic Shaper (traffic shaping)
  • PSE Power Source Equipment (PoE)
  • PT Payload Type (RTP)
  • PTM Precision Time Measurement (PTM) PCI-SIG ECN (PCIe devices)
  • PTO Presentation Time Offset
  • PTP Precision Time Protocol, part of IEEE 1588-2002 and IEEE 1588-2008 (not backward comptabile), hierarchical master-slave architecture for clock distribution
  • PTPDEV PTP Deviation
  • PVID Port Vlan ID, C’est le VLAN auquel un port est associé. La notion de PVID permet donc de savoir dans quel VLAN se situe ce port. Un port ne peut avoir qu’un seul PVID.
  • PoE plus see IEEE 802.3at
  • PoE+ aka PoE plus, see IEEE 802.3at
  • POF Plastic Optic Fiber


  • Q-in-Q used for PB
  • QCN Quantized Congestion Notification
  • QFQ Quick Fair Queueing (traffic control)
  • QPC quadlet padding count
  • QoS quality of service


  • RA Router Advertisement (routing, multicast, IGMP)
  • RDI Remote Defect Indication
  • RDMA Remote Direct Memory Access
  • RED Random Early Detection (traffic control)
  • RevCom Standards Review Committee (IEEE)
  • RF4CE Radio Frequency for Consumer Electronics (remote control)
  • RFC 2544 Benchmarking Methodology for Network Interconnect Devices (IETF)
  • RFC 2889 Benchmarking Methodology for LAN Switching Devices (IETF)
  • RFC 4789 Simple Network Management Protocol (SNMP) over IEEE 802 Networks (IETF)
  • RFC 6184 RTP Payload Format for H.264 Video (IETF)
  • RFM Reflected Frame Message (IEEE)
  • RMA Return Merchandise Authorization (business)
  • RMII Reduced Media Independent Interface
  • RMON Request MONitoring, le standard RMON 1 (RFC 2819, 3577, 4502) a été créé initialement pour avoir des informations sur les échanges réseau dans les couches physique et liaison (Physical et logical link layer), ex quantité de paquets et d’octets reçus et transmis globalement sur le segment, quantité de paquets de broadcast, de multicast et d’erreurs globalement sur le segment…
  • RP Reaction Point (IEEE)
  • RPS Receive Packet Steering (Linux)
  • RPT return path test (IEEE)
  • RR Receiver Report (RTP)
  • RR Reflection Responder (IEEE)
  • RSE Rear Seat Entertainment system (IVI)
  • RSE Road Side Equipment (C2I)
  • RSPEC service Request SPECification
  • RST BPDU Rapid Spanning Tree Bridge Protocol Data Unit (IEEE)
  • RSTP Rapid Spanning Tree Algorithm and Protocol (IEEE)
  • RSVP Resource reSerVation Protocol (IETF QoS)
  • RSVP-TE Resource Reservation Protocol-Traffic Engineering (QoS, IETF RFC 5151)
  • RTCP RTP Control Protocol (IETF, IEEE 1733)
  • RTP Real-time Transport Protocol (IETF, IEEE 1733)
  • RTPGE Reduced Twisted Pair Gigabit Ethernet, IEEE 802.3bp
  • RTSP Real-time Streaming Protocol (IETF, IEEE 1733)
  • RTT Round Trip Time
  • RTTI Real-time Traffic and Travel Information
  • runt frame an Ethernet frame shorter than 64 bytes (IEEE) see also jabber frame
  • RVF Raw Video Format (IEEE P1722a)
  • RVI Routed VLAN Interface, SVI for some vendors (including Cisco)
  • RoCE RDMA over Converged Ethernet
  • Rsv reserved


  • S-VID Service VLAN ID
  • S-VLAN Service VLAN
  • S-tag Service TAG
  • S/PDIF Sony/Philips Digital Interface Format, a consumer-grade variant of AES3
  • SA Source Address
  • SAE AS6802 Time Triggered Ethernet
  • SAP Service Access Point (IEEE 802.2) The LLC Header consist of three fields, namely DSAP (Destination Service Access Point), SSAP (Source Service Access Point), and Control.
  • SAR Sample Aspect Ratio (RTP H.264)
  • SAV Start of Active Video, byte sequence defined by ITU-R BT.656
  • SAW Smart Antenna Window
  • SC Standard Comitee (IEEE)
  • SCC Standard Coordinating Comitee (IEEE)
  • SCTP Stream Control Transmission Protocol
  • SEI Supplemental Enhancement Information (RTP H.264)
  • SFQ Synchronized Forwarding and Queuing (formerly called “peristaltic shaping”) (TSN)
  • SerDes serializer and deserializer (FPD-Link II & III)
  • SDES Source Description Items (RTP)
  • SDH Synchronous Digital Hierarchy
  • SDI Serial Digital Interface (video SMPTE)
  • SDN Software Defined Network
  • SDO Standards Developing Organization (ex IEEE, IETF, W3C, UTI…)
  • SDP Session Description Protocol, as defined by RFC 4566
  • SDR Software-Defined Radio
  • SDU Service Data Unit
  • SFD Start of Frame Delimiter
  • SFD Stream Format Descriptor
  • SFM Send Frame Message (IEEE CFM)
  • SFM Single Figure of Merit (performances)
  • SFP Small Form-factor Pluggable transceiver
  • SFQ Stochastic Fairness Queueing (traffic control)
  • SID source identifier
  • SIP Session Initiation Protocol (RTP)
  • SME Station Management Entity (Ethernet PHY)
  • SME Station Management Entity (Wi-Fi IEEE 802.11)
  • SMI Serial Management Interface, aka MDIO, used to transfer management information between MAC and PHY.
  • SMI Structure of Management Information (IETF RFC 2578, SMIv2)
  • SMPTE Society of Motion Picture and Television Engineers
  • SNAP Subnetwork Access Protocol, IEEE 802.3, SNAP Frame Format consists of a normal 802.3 Data Link Header followed by a normal 802.2 LLC Header, and then a 5 byte SNAP field, followed by the normal user data and FCS.
  • SN Sequence Number (RTP)
  • SNMP Simple Network Management Protocol
  • SNTP Simple Network Time Protocol
  • SOME/IP Scalable service-Oriented MiddlewarE over IP (AUTOSAR)
  • SONET Synchronous Optical Networking
  • SOTA Software Over-The-Air
  • SPAN Switched Port ANalyzer (Cisco)
  • SPB Shortest Path Bridging
  • SPBM Shortest Path Bridging MAC
  • SPBV Shortest Past Bridging VIDSPH source packet header
  • SPN Suspect Parameter Number
  • SPQ Strict Priority Queuing
  • SPT Shortest Path Tree
  • SPnP Static priority non-preemptive (scheduling)
  • SR Sender Report (RTP)
  • SR stream reservation (IEEE Std 802.1Q)
  • SRC Sample Rate Conversion
  • SRP Stream Reservation Protocol, aka IEEE 802.1Qat incorporated in IEEE 802.1Q-2011
  • SR_PVID Stream Reservation Port VLAN Identifier (IEEE Std 802.1Q)
  • SSM Source Specific Multicast
  • SSRC Synchronisation Source identifier (RTP)
  • SST Single Spanning Tree (IEEE)
  • SSTP Shielded Shielded Twisted Pair
  • ST BPDU Spanning Tree Bridge Protocol Data Unit (IEEE)
  • STAP Single-Time Aggregation Packet (RTP H.264)
  • STAP-A STAP type A (RTP H.264)
  • STAP-B STAP type B (RTP H.264
  • STC Symphony Teleca Corporation (company)
  • STP Shielded Twisted Pair
  • STP Spanning Tree Algorithm and Protocol (IEEE 802.1D)
  • SVI Switch virtual interface, RVI for some vendors
  • SVL Shared Virtual Local Area Network (VLAN) Learning (IEEE)
  • SWAVI Synchronized Wireless Audio & Video Interoperability (AVnu, Wireless TSN)
  • SYT synchronization timing


  • TA Talker Advertisement (AVB)
  • TA Target Address
  • TAI Marvell, Time Application Interface
  • TAI Temps Atomique International (ahead of UTC by 35 seconds)
  • TAS Time Aware Shaper
  • TBF Token Bucket Filter (traffic control)
  • TC Textual Convention (IETF et IEEE MIB)
  • TC Traffic Control (Linux)
  • TC Transmission Convergence (Ethernet, a sublayer of PCS)
  • TC Transparent Clock
  • TCAM Ternary CAM (Ethernet)
  • TDEV time deviation
  • TDM Time Division Multiplexing
  • TDMA Time Division Multiple Access
  • TE Traffic Engineering (IEEE)
  • TE-SID Traffic Engineering service instance identifier (IEEE)
  • TESI Traffic Engineering service instance (IEEE)
  • TISA Traveller Information Service Association
  • TLV Type, Length, Value (according to 802.1AVB)
  • TOD Time Of Departure (IEEE 802.11)
  • TOE TCP Offload Engine
  • TPCE Twisted Pair 100 Mbit/s Ethernet (IEEE non-proprietary version of Broadcom’s BroadR’Reach)
  • TPID Tagged protocol identifier (81-0016 as defined in IEEE Std 802.1Q aka VLAN)
  • TPMR Two-Port Media Access Control (MAC) Relay (IEEE)
  • TS Timestamp (RTP H.264)
  • TSCF Time Sensitive Control Format (IEEE P1722a)
  • TSCS Time Sensitive Control Stream
  • TSN Time Sensistive Networking, a sub-group from IEEE 802, formerly namedAVB
  • TSNA Time-Sensitive Networking Task Group (IEEE)
  • TSO TCP segmentation offload
  • TSP transport stream packet
  • TSpec Traffic SPECification
  • TTE Time Triggered Ethernet, SAE AS6802
  • TTEthernet (SAE AS6802) a computer network technology marketed by TTTech Computertechnik AG for use in airplanes and other real-time applications.
  • TTL Time To Live
  • TWG Technical Work Group (AVnu SIG)
  • TXOP Transmission Opportunity (Wi-Fi QoS)


  • UBS Urgency Based Scheduler (TSN)
  • UDP-NM UDP Network Management (AUTOSAR )
  • UDS UNIX domain sockets (linuxptp, “/var/run/ptp4l”)
  • UDS Unified Diagnostic Services, ISO 14229 (DoIP)
  • UDSonIP Unified diagnostic services on Internet Protocol implementation, ISO 14229-5
  • UIBC User Input Back Channel (Wi-Fi)
  • UNI User to Network Interface
  • UTC coordinated universal time
  • UTP unshielded twisted pair
  • UUID Universally unique identifier (ISO/IEC, ITU, IETF RFC4122)


  • V2G Vehicule To Grid, battery to grid applied to vehicule
  • VANC Vertical Ancillary Data
  • VCIC road vehicles Video communication interface for cameras, ISO 17215 (ADAS)
  • VCL Video Coding Layer (H.264)
  • VCT Virtual Cable Tester, technologie Marvell de diagnostic de probleme de cable
  • VDP VSI Discovery and Configuration Protocol(IEEE 802.1Qbg)
  • VDSPC Video Data Source Packet Count
  • VFTA VLAN Filter Table Array
  • VID VLAN identifier (IEEE Std 802.1Q) ISO 3779
  • VIN Vehicule Identification Number, ISO 3779
  • VIP Virtual Instance Port (IEEE)
  • VLAN TCI VLAN Tag Control Information, contain PCP, DEI
  • VLAN Virtual Local Area Network
  • VN Virtual Network
  • VPN Virtual Private Network, as defined in RFC 2764
  • VSI Virtual Service Instance
  • VUI Video Usability Information (RTP H.264)
  • VXLAN Virtual Extensible LAN


  • WAVE Wireless Access in Vehicular Environments (see also IEEE 1609, IEEE 802.11p) (V2V, V2I)
  • WFA short for Wi-Fi Alliance
  • WFD short for Wi-Fi Direct (aka Wi-Fi p2p)
  • WFQ Weighted Fair Queuing (scheduling)
  • WG Working Group (IEEE)
  • WME Wireless Multimedia Extensions (Wi-Fi QoS)
  • WNM Wireless Network Management (Wi-Fi Alliance)
  • WPAN Wireless Personal Area Network (Bluetooth, ZigBee…)
  • WRR Weighted Round Robin (scheduling)
  • WSP Weighted Strict Priority (scheduling)
  • WUP Wake-up Pattern
  • WMM Wi-Fi Multimedia (Wi-Fi QoS)
  • WiMob Wireless and Mobile Computing, Networking And Communications (IEEE)


  • XPS Transmit Packet Steering (Linux)


  • YANG a data modeling language for NETCONF (see NETCONF, ETF RFC 6241)

Some mysterious ones – any ideas?

  • IB-BEB ???
  • MCN ??? (“MCN needs MAC address”)
  • PCE ?
  • RPFC ?
  • STU ??? Marvell swcfg, “STU table access”
  • TE-MSTI ?
  • VTU ? VLAN Table U?, Vlan Id table ?