5 ms·

HTTP isn't the only L7 protocol.

by xxpor 7y ago

kazen44 7y ago
this. Many people here seem to not realize that TCP is used for much more then just http/https. Quick might be nice for web traffic, but i see little reason to use it as an underlay for BGP for instance.
- CameronNemo 7y ago
  I have not thought much about how BGP would react to QUIC as transport, would be curious to hear your thoughts on the matter.
  - kazen44 7y ago
    for one, not having hardware acceleration makes quic very slow compared to TCP. This is especially a problem on firewalls, as they need to tear apart and reassemble tcp packets at line speed. In terms of BGP and quic as a transport. As far as i know, quic is not backwards compatible with TCP, and having two different transport protocols for the routing protocols that ties the internet together would be problematic in terms of migration. Im not entirely up to speed in terms of how quick would handle MSS size, but this could pose a problem in some situations.
    - fart_ratty 7y ago
      BGP not having security has caused many problems.
      - CameronNemo 7y ago
        BGP has some security. It's called rpki and the industry is slowly adopting it.
      - allarm 7y ago
        BGP over some new fancy transport protocol will cause way more problems.
        CameronNemo 7y ago
        Practically? Yes it will cause all kinds of chaos. Theoretically? Depends on the transport and it's characteristics. There could be a theoretical gain to using something else.
    - CameronNemo 7y ago
      I imagine it would be fairly simple to teach a BGP implementation to use either TCP or QUIC, configurable per-session. Firewalls that dig deep into tcp packets sound like troublesome middleware with which good actors are in an arms, not something to go out of the way to support. I'll have to look into potential MSS issues.
- jeltz 7y ago
  And why would QUIC not work for other streaming protocols? the only possible disadvantages I can see is that it is a bit more complex and that it requires encryption. It does not in any way require HTTP.
JoshTriplett 7y ago
The current version of QUIC is designed to support HTTP/3, but the QUIC roadmap includes support for other protocols as well.
- detaro 7y ago
  I thought IETF QUIC was higher-level agnostic from the beginning, has that changed?
  - jeltz 7y ago
    No, it has not changed.
  - Matthias247 7y ago
    It is. The bare API of QUIC would now mostly look just like TCP/IP streams. You have bidirectional byte streams with flow-control. The main difference from an API pointer of view is that there is an additional multiplexing layer. On TCP/IP the byte stream is directly on the connection. On QUIC a connection can contain multiple streams - which are openable by both sides. And each of those streams is a bidirectional or unidirectional byte streams. QUIC doesn't care what protocol you run on top of those streams. HTTP/3 is just the only one which is specified at the moment.
jchw 7y ago
Nothing prevents you from using QUIC as a replacement for TCP AFAIK - on the surface it seems like it would be potentially useful for more applications than HTTP. May even be a decent option for video games and other things that need somewhat lower latency and wish to avoid head-of-line blocking.
- CameronNemo 7y ago
  Seeing a BGP implementation running over QUIC would be the end game, right? There is so mug network hardware which will not be replaced for decades, so people would have to get started now if they wanted to completely make TCP redundant in the not so near future.
- chungy 7y ago
  > May even be a decent option for video games and other things that need somewhat lower latency and wish to avoid head-of-line blocking. Most video games already use UDP
  - jchw 7y ago
    Sure. In fact most video games use some kind of networking middleware. But tbh, a lot of them are not so great because a lot of concerns get mixed together, and if you want a reliable connection with congestion control you likely will just open a TCP connection somewhere with a different protocol. For the hobbyist world, this option as a low level transport is not so bad imo. Like as a replacement for ENet which does not have IPv6 support today seems reasonable.
  - jayd16 7y ago
    lots of games use UDP, lots of games use TCP. I could easily see games using QUIC. If you include mobile games, I doubt most games have the budget to tune a UDP stack.
- marcthe12 7y ago
  QUIC seems to have encryption so something like SSH could come

HTTP isn't the only L7 protocol.

by xxpor 7y ago

HTTP isn't the only L7 protocol.

this. Many people here seem to not realize that TCP is used for much more then just http/https. Quick might be nice for web traffic, but i see little reason to use it as an underlay for BGP for instance.

CameronNemo 7y ago
I have not thought much about how BGP would react to QUIC as transport, would be curious to hear your thoughts on the matter.
- kazen44 7y ago
  for one, not having hardware acceleration makes quic very slow compared to TCP. This is especially a problem on firewalls, as they need to tear apart and reassemble tcp packets at line speed. In terms of BGP and quic as a transport. As far as i know, quic is not backwards compatible with TCP, and having two different transport protocols for the routing protocols that ties the internet together would be problematic in terms of migration. Im not entirely up to speed in terms of how quick would handle MSS size, but this could pose a problem in some situations.
  - fart_ratty 7y ago
    BGP not having security has caused many problems.
    - CameronNemo 7y ago
      BGP has some security. It's called rpki and the industry is slowly adopting it.
    - allarm 7y ago
      BGP over some new fancy transport protocol will cause way more problems.
      - CameronNemo 7y ago
        Practically? Yes it will cause all kinds of chaos. Theoretically? Depends on the transport and it's characteristics. There could be a theoretical gain to using something else.
  - CameronNemo 7y ago
    I imagine it would be fairly simple to teach a BGP implementation to use either TCP or QUIC, configurable per-session. Firewalls that dig deep into tcp packets sound like troublesome middleware with which good actors are in an arms, not something to go out of the way to support. I'll have to look into potential MSS issues.
jeltz 7y ago
And why would QUIC not work for other streaming protocols? the only possible disadvantages I can see is that it is a bit more complex and that it requires encryption. It does not in any way require HTTP.

JoshTriplett 7y ago

The current version of QUIC is designed to support HTTP/3, but the QUIC roadmap includes support for other protocols as well.

detaro 7y ago
I thought IETF QUIC was higher-level agnostic from the beginning, has that changed?
- jeltz 7y ago
  No, it has not changed.
- Matthias247 7y ago
  It is. The bare API of QUIC would now mostly look just like TCP/IP streams. You have bidirectional byte streams with flow-control. The main difference from an API pointer of view is that there is an additional multiplexing layer. On TCP/IP the byte stream is directly on the connection. On QUIC a connection can contain multiple streams - which are openable by both sides. And each of those streams is a bidirectional or unidirectional byte streams. QUIC doesn't care what protocol you run on top of those streams. HTTP/3 is just the only one which is specified at the moment.

jchw 7y ago

Nothing prevents you from using QUIC as a replacement for TCP AFAIK - on the surface it seems like it would be potentially useful for more applications than HTTP. May even be a decent option for video games and other things that need somewhat lower latency and wish to avoid head-of-line blocking.

CameronNemo 7y ago
Seeing a BGP implementation running over QUIC would be the end game, right? There is so mug network hardware which will not be replaced for decades, so people would have to get started now if they wanted to completely make TCP redundant in the not so near future.
chungy 7y ago
> May even be a decent option for video games and other things that need somewhat lower latency and wish to avoid head-of-line blocking. Most video games already use UDP
- jchw 7y ago
  Sure. In fact most video games use some kind of networking middleware. But tbh, a lot of them are not so great because a lot of concerns get mixed together, and if you want a reliable connection with congestion control you likely will just open a TCP connection somewhere with a different protocol. For the hobbyist world, this option as a low level transport is not so bad imo. Like as a replacement for ENet which does not have IPv6 support today seems reasonable.
- jayd16 7y ago
  lots of games use UDP, lots of games use TCP. I could easily see games using QUIC. If you include mobile games, I doubt most games have the budget to tune a UDP stack.
marcthe12 7y ago
QUIC seems to have encryption so something like SSH could come