4 ms·

Ethernet over HDMI is interesting.

by 0xEFF 7y ago

ComputerGuru 7y ago
No, it’s a complete no-go. HDMI 1.4 is 10GT/s but only in one direction (your PC streams content to the display, there is no need for the other way around). Newer versions have limited bandwidth in the reverse direction to support things like CEC and ARC, but nothing substantial.
- Eikon 7y ago
  Wouldn’t that work using cards having both hdmi in and hdmi out, using two hdmi cables for duplex?
  - ComputerGuru 7y ago
    What would the benefit be? Cat5E can carry 10g, is cheaper, and you only need one cable. You have twice as many connections, twice as many PHY components, twice as many points of failure, etc etc if you go with two HDMI cables instead.
    - 0xEFF 7y ago
      The benefit would be the GPU manipulating and filtering packets without the data hitting the PCI bus or the CPU. Imagine a firewall operating at 80 Gbit/sec with no CPU utilization.
- w7 7y ago
  Some Dell enterprise switches actually used HDMI for stacking[0]. Image: https://kbimg.dell.com/library/KB/DELL_ORGANIZATIONAL_GROUPS/DELL_GLOBAL/Dell_Networking/5500%20Stack.png https://kbimg.dell.com/library/KB/DELL_ORGANIZATIONAL_GROUPS... But it's not a common thing and I believe is outmoded. [0] https://www.dell.com/support/article/us/en/04/how10728/how-to-stack-dell-networking-powerconnect-5500-model-switches?lang=en https://www.dell.com/support/article/us/en/04/how10728/how-t...
  - pbalau 7y ago
    Is that HDMI protocol or HDMI cables? There are a bunch of sensors that use ethernet connectors, but have nothing to do with networks
    - w7 7y ago
      Just cables.
  - ComputerGuru 7y ago
    Clever. Stacking necessarily requires a loop, so you can just use unidirectional data flow and you don’t need 2x cables. Or perhaps they use a proprietary half-duplex implementation over the single channel, which would allow for it to continue working with a device out. I can’t see why, though. It can’t be cheaper (and they have to license the HDMI spec).
0xEFF 7y ago
Not quite sure why my comment got downvoted so heavily. My point is a commodity GPU is attached to 4 physical ports, each capable of 80 Gbit/sec for a total bandwidth of 320 Gbit/sec with DP 2.0. The GP's comment on using the GPU for offloading is interesting. There's a physical link connected directly to the GPU without having to go over the PCI bus or through the CPU. Bi-directional also doesn't matter. Many applications are uni-directional or async. I could easily see a situation where one DP link is used for upstream and 3 DP links are used for downstream, or even all DP links for one direction and a traditional interface used for upstream.

Ethernet over HDMI is interesting.

by 0xEFF 7y ago

Ethernet over HDMI is interesting.

No, it’s a complete no-go. HDMI 1.4 is 10GT/s but only in one direction (your PC streams content to the display, there is no need for the other way around). Newer versions have limited bandwidth in the reverse direction to support things like CEC and ARC, but nothing substantial.

Eikon 7y ago
Wouldn’t that work using cards having both hdmi in and hdmi out, using two hdmi cables for duplex?
- ComputerGuru 7y ago
  What would the benefit be? Cat5E can carry 10g, is cheaper, and you only need one cable. You have twice as many connections, twice as many PHY components, twice as many points of failure, etc etc if you go with two HDMI cables instead.
  - 0xEFF 7y ago
    The benefit would be the GPU manipulating and filtering packets without the data hitting the PCI bus or the CPU. Imagine a firewall operating at 80 Gbit/sec with no CPU utilization.
w7 7y ago
Some Dell enterprise switches actually used HDMI for stacking[0]. Image: https://kbimg.dell.com/library/KB/DELL_ORGANIZATIONAL_GROUPS/DELL_GLOBAL/Dell_Networking/5500%20Stack.png https://kbimg.dell.com/library/KB/DELL_ORGANIZATIONAL_GROUPS... But it's not a common thing and I believe is outmoded. [0] https://www.dell.com/support/article/us/en/04/how10728/how-to-stack-dell-networking-powerconnect-5500-model-switches?lang=en https://www.dell.com/support/article/us/en/04/how10728/how-t...
- pbalau 7y ago
  Is that HDMI protocol or HDMI cables? There are a bunch of sensors that use ethernet connectors, but have nothing to do with networks
  - w7 7y ago
    Just cables.
- ComputerGuru 7y ago
  Clever. Stacking necessarily requires a loop, so you can just use unidirectional data flow and you don’t need 2x cables. Or perhaps they use a proprietary half-duplex implementation over the single channel, which would allow for it to continue working with a device out. I can’t see why, though. It can’t be cheaper (and they have to license the HDMI spec).

0xEFF 7y ago

Not quite sure why my comment got downvoted so heavily. My point is a commodity GPU is attached to 4 physical ports, each capable of 80 Gbit/sec for a total bandwidth of 320 Gbit/sec with DP 2.0. The GP's comment on using the GPU for offloading is interesting. There's a physical link connected directly to the GPU without having to go over the PCI bus or through the CPU. Bi-directional also doesn't matter. Many applications are uni-directional or async. I could easily see a situation where one DP link is used for upstream and 3 DP links are used for downstream, or even all DP links for one direction and a traditional interface used for upstream.