5 ms·

Would this make ssh more robust against intermittent connectivity? like https://mosh.org/ https://mosh.org/ without needing to run mosh on the server

FrancoisBosun 3y ago
Mosh has latency-hiding mechanisms. I used mosh for a bit on while riding a bus. Latency-hiding helped quite a bit to keep the UI responsive.
- cl3misch 3y ago
  Do you mean UI as in X forwarding? I thought this wasn't possible, which kept me from using mosh so far.
  - NoZebra120vClip 3y ago
    The "G" in "GUI" stands for "graphical". Some people use "TUI" to mean "Terminal User Interface". It therefore follows that someone using merely "UI" has not specified the type of interface.
  - tempay 3y ago
    They mean UI as in for command lines, like vim/emacs/shells
    - egberts1 3y ago
      TUI, better? UI is just plain ol' things for user to interact with computer.
ori_b 3y ago
Mosh is closer to tmux than to ssh.
- talideon 3y ago
  Any similarity with tmux is purely because it's connectionless. It's mostly certainly more like ssh than it is like tmux. Both are remote shell protocols, while tmux is simply a terminal multiplexer.
  - deleted 3y ago
    [deleted]
  - hackernudes 3y ago
    Mosh is a terminal emulator itself and sends the diff of the output from the server to the client. Ssh just passes the terminal data through. I think that is why mosh is like tmux, because tmux is also a terminal emulator.
  - loxias 3y ago
    Mosh is not at all like ssh, tries hard to avoid duplicating ssh functionality, and this is by design. If it were like ssh the authors would have had to then handle security/authentication and all that jazz perfectly. It was written to "stand on the shoulders" of ssh, except handle terminal emulation and UTF-8 correctly. By using ssh, you don't have to trust "some new thing" as long as you trust ssh. It's not even a shell protocol if you think about it! Mosh bidirectionally synchronizes the state between the terminal window on the client and the virtual terminal on the server. It runs at a frame rate, which results in not filling intermediate network queues, which is where the low latency comes from. :)
    - talideon 3y ago
      > It's not even a shell protocol if you think about it! Nor is SSH. Feel free to take a read over the RFCs. There's next to no 'sh' in SSH as a protocol. What mosh adds to SSH is the ability to securely resume a session. SSH is fundamentally protocol for setting up a secure connection and then ping-pong messages back and forth. tmux runs locally. It's not a network daemon. The complexion of a daemon and protocol meant to operate over a network is very, very different from one intended to run over Unix domain sockets or on the loopback interface.
LinuxBender 3y ago
Probably only if this implements a similar roaming concept as mosh by using a nonce or something along that line vs. ssh session keys that are mapped to an IP. Mosh was designed by MIT folks not just for high latency but also mobile networks which can change IP and lose connectivity frequently. Perhaps the code author is here on HN?
- Avamander 3y ago
  It doesn't have to be this piece of software implementing MP-UDP for roaming to work though. Nevertheless I doubt it has such functionality right now.
- loxias 3y ago
  Mosh was designed for a great number of things, including what you mentioned. To me, mosh is "careful and impressively pedantically correct UTF-8 terminal emulator" + "careful and impressively pedantically correct state synchronization protocol". :)

FrancoisBosun 3y ago

Mosh has latency-hiding mechanisms. I used mosh for a bit on while riding a bus. Latency-hiding helped quite a bit to keep the UI responsive.

cl3misch 3y ago
Do you mean UI as in X forwarding? I thought this wasn't possible, which kept me from using mosh so far.
- NoZebra120vClip 3y ago
  The "G" in "GUI" stands for "graphical". Some people use "TUI" to mean "Terminal User Interface". It therefore follows that someone using merely "UI" has not specified the type of interface.
- tempay 3y ago
  They mean UI as in for command lines, like vim/emacs/shells
  - egberts1 3y ago
    TUI, better? UI is just plain ol' things for user to interact with computer.

ori_b 3y ago

Mosh is closer to tmux than to ssh.

talideon 3y ago
Any similarity with tmux is purely because it's connectionless. It's mostly certainly more like ssh than it is like tmux. Both are remote shell protocols, while tmux is simply a terminal multiplexer.
- deleted 3y ago
  [deleted]
- hackernudes 3y ago
  Mosh is a terminal emulator itself and sends the diff of the output from the server to the client. Ssh just passes the terminal data through. I think that is why mosh is like tmux, because tmux is also a terminal emulator.
- loxias 3y ago
  Mosh is not at all like ssh, tries hard to avoid duplicating ssh functionality, and this is by design. If it were like ssh the authors would have had to then handle security/authentication and all that jazz perfectly. It was written to "stand on the shoulders" of ssh, except handle terminal emulation and UTF-8 correctly. By using ssh, you don't have to trust "some new thing" as long as you trust ssh. It's not even a shell protocol if you think about it! Mosh bidirectionally synchronizes the state between the terminal window on the client and the virtual terminal on the server. It runs at a frame rate, which results in not filling intermediate network queues, which is where the low latency comes from. :)
  - talideon 3y ago
    > It's not even a shell protocol if you think about it! Nor is SSH. Feel free to take a read over the RFCs. There's next to no 'sh' in SSH as a protocol. What mosh adds to SSH is the ability to securely resume a session. SSH is fundamentally protocol for setting up a secure connection and then ping-pong messages back and forth. tmux runs locally. It's not a network daemon. The complexion of a daemon and protocol meant to operate over a network is very, very different from one intended to run over Unix domain sockets or on the loopback interface.

LinuxBender 3y ago

Probably only if this implements a similar roaming concept as mosh by using a nonce or something along that line vs. ssh session keys that are mapped to an IP. Mosh was designed by MIT folks not just for high latency but also mobile networks which can change IP and lose connectivity frequently. Perhaps the code author is here on HN?

Avamander 3y ago
It doesn't have to be this piece of software implementing MP-UDP for roaming to work though. Nevertheless I doubt it has such functionality right now.
loxias 3y ago
Mosh was designed for a great number of things, including what you mentioned. To me, mosh is "careful and impressively pedantically correct UTF-8 terminal emulator" + "careful and impressively pedantically correct state synchronization protocol". :)