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GeneralRe: SpaceX’s second Starship flight test ends in an explosion minutes after launch Pin
jeron120-Nov-23 7:20
jeron120-Nov-23 7:20 
GeneralRe: SpaceX’s second Starship flight test ends in an explosion minutes after launch Pin
Daniel Pfeffer20-Nov-23 9:33
professionalDaniel Pfeffer20-Nov-23 9:33 
NewsEthernet is still going strong after 50 years Pin
Kent Sharkey19-Nov-23 10:16
staffKent Sharkey19-Nov-23 10:16 
JokeRe: Ethernet is still going strong after 50 years Pin
Daniel Pfeffer19-Nov-23 20:51
professionalDaniel Pfeffer19-Nov-23 20:51 
GeneralRe: Ethernet is still going strong after 50 years Pin
trønderen19-Nov-23 23:20
trønderen19-Nov-23 23:20 
GeneralRe: Ethernet is still going strong after 50 years Pin
obermd20-Nov-23 4:18
obermd20-Nov-23 4:18 
GeneralRe: Ethernet is still going strong after 50 years Pin
Daniel Pfeffer20-Nov-23 4:28
professionalDaniel Pfeffer20-Nov-23 4:28 
GeneralRe: Ethernet is still going strong after 50 years Pin
trønderen20-Nov-23 7:41
trønderen20-Nov-23 7:41 
"Communication protocols" come at various layers, each covering a varying set of functionalities. The original Ethernet was a pure physical layer. Splitting off some parts of it to a link layer came later. Even today, Ethernet does not at all affect anything above the link layer.

I must admit that I never studied the medium access control in star topography, RJ45-style Ethernet, so for all I know, what used to be CSMA/CD for medium access, it could be that nowadays, CSMA/CD is used for access not to the medium, but to the router. I sort of doubt it, though. Each device has a dedicated cable to the router, no "Multiple Access". A router could of course broadcast some sort of carrier to all other devices rather than the one currently active, to keep them from trying to start transmission. I doubt it. Wikipedia says not. Every connection to the router has its own electronics, with its own flow control.

When I learned about Ethernet as a young student, CSMA/CD was an essential part of the protocol discussion, distinguishing it from e.g. Token Ring or DQDB.

When you run Ethernet over WiFi, is the original coax-oriented CSMA/CD used for access to the air waves?

The original Ethernet protocol was half duplex (obviously, since there was a single physical medium). All documentation I can find of RJ45 based Ethernet claims that it is full duplex.

48 bit Ethernet physical addresses were used for direct physical identification of sender and receiver, handled at the physical layer, by the physical interface. All devices were on the same cable, so there was no 'routing' beyond this; an interface forwarded to its device frames with matching 48 bit address (or a broadcast address) and ignored all other packets. Is that still how this 48 bit address is used?

The original Ethernet could work with 16 bit physical addresses. Is that still supported?

The original transmission mode was plain unconfirmed datagram (connectionless) transmission. Is that still the case?

The payload size was limited to 1500 bytes. Is that still the case?

Is the 'EtherType' field of the frame unchanged from the original definition?
(Actually, the 1976 Metcalfe et. al. paper shows a frame with no EtherType at all.)

Is the frame check sequence (CRC) calculation unchanged from the original definition?

Is the 'end of frame' indication unchanged from the original definition?

Which parts of the 1973 Ethernet protocol have not changed?
GeneralRe: Ethernet is still going strong after 50 years Pin
obermd21-Nov-23 4:11
obermd21-Nov-23 4:11 
GeneralRe: Ethernet is still going strong after 50 years Pin
trønderen21-Nov-23 6:09
trønderen21-Nov-23 6:09 
NewsAmazon will allow auto dealers to sell cars on its site, starting with Hyundai Pin
Kent Sharkey19-Nov-23 10:16
staffKent Sharkey19-Nov-23 10:16 
GeneralRe: Amazon will allow auto dealers to sell cars on its site, starting with Hyundai Pin
Nelek20-Nov-23 9:03
protectorNelek20-Nov-23 9:03 
GeneralRe: Amazon will allow auto dealers to sell cars on its site, starting with Hyundai Pin
MarkTJohnson20-Nov-23 10:37
professionalMarkTJohnson20-Nov-23 10:37 
NewsHow one line of code caused a $60 million loss Pin
Kent Sharkey19-Nov-23 10:16
staffKent Sharkey19-Nov-23 10:16 
GeneralRe: How one line of code caused a $60 million loss Pin
Nelek20-Nov-23 9:00
protectorNelek20-Nov-23 9:00 
NewsNASA probe transmits groundbreaking laser message from 10 million miles away Pin
Kent Sharkey19-Nov-23 10:01
staffKent Sharkey19-Nov-23 10:01 
GeneralRe: NASA probe transmits groundbreaking laser message from 10 million miles away Pin
Nelek20-Nov-23 9:02
protectorNelek20-Nov-23 9:02 
NewsThe Visual Studio UI Refresh Preview is here! Pin
Kent Sharkey19-Nov-23 10:01
staffKent Sharkey19-Nov-23 10:01 
GeneralRe: The Visual Studio UI Refresh Preview is here! Pin
Nelek20-Nov-23 9:02
protectorNelek20-Nov-23 9:02 
NewsMicrosoft will let users uninstall Edge, Bing, and disable ads on Windows 11 as it complies with the Digital Markets Act Pin
Kent Sharkey19-Nov-23 10:01
staffKent Sharkey19-Nov-23 10:01 
GeneralRe: Microsoft will let users uninstall Edge, Bing, and disable ads on Windows 11 as it complies with the Digital Markets Act Pin
Nelek20-Nov-23 9:01
protectorNelek20-Nov-23 9:01 
GeneralRe: Microsoft will let users uninstall Edge, Bing, and disable ads on Windows 11 as it complies with the Digital Markets Act Pin
Kent Sharkey20-Nov-23 10:27
staffKent Sharkey20-Nov-23 10:27 
GeneralRe: Microsoft will let users uninstall Edge, Bing, and disable ads on Windows 11 as it complies with the Digital Markets Act Pin
Nelek21-Nov-23 9:14
protectorNelek21-Nov-23 9:14 
NewsOpenAI ousted CEO Sam Altman, but is reportedly reconsidering the move Pin
Kent Sharkey19-Nov-23 10:01
staffKent Sharkey19-Nov-23 10:01 
GeneralRe: OpenAI ousted CEO Sam Altman, but is reportedly reconsidering the move Pin
Nelek20-Nov-23 9:00
protectorNelek20-Nov-23 9:00 

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