When comparing PuTTY vs Ásbrú Connection Manager, the Slant community recommends PuTTY for most people. In the question“What are the best SSH clients for Linux?” PuTTY is ranked 3rd while Ásbrú Connection Manager is ranked 6th.
Ranked in these QuestionsQuestion Ranking
Pro De facto standard client for SSH, Telnet and Rlogin on Windows
PuTTY is one of the oldest and most popular clients. It has earned the trust of a great number of users over a long period by being reliable, offering useful features and helpful support. It got into the 15 Essential Open Source Tools for Windows Admins list by InfoWorld.
Pro Can be used on any Windows computer, even without admin rights
Pro Source code available
Full source available. Compile and modify it yourself.
Pro Lightweight and portable
Doesn't require much resources (memory and hard-disk). Can even be run on a system by just downloading without install.
Pro Many supported protocols
SSH1/2, Mosh, FTP, SFTP, VNC, RDP, Telnet, Serial, WebDAV, and IBM 3270/5250
Pro Logical grouping of connections
Groups and subgroups can be created, and connections put in them, to organize a large amount of connections so that you can get more done with the program
If you were looking for this feature from SecureCRT, it's here
Pro Local terminal tab
Easy access to the local machine's command-line interface is provided by a dedicated tab shown adjacent to the tabs for all remote connections.
Pro Split-display support
Built-in support to split a single tabbed connection display into upper/lower or left/right halves as well as quartered. No need to use tmux, screen or the like.
Pro Scripting support with custom triggers
Most actions that can be performed over SSH can be scripted and set to run on a schedule, automatically upon connection, or in response to a received message or prompt.
Pro KeePassX integration
Authentication credentials and SSH keyfile passphrases can be supplied by KeePassX rather than being saved in the application's settings.
Pro Great community support
Very active project on their GitHub page with a lot of interactions from all over the world.
Pro Per-connection proxy settings
Use different proxies for different simultaneous remote host connections if desired
Pro History sidebar
All terminals have a command history of some sort, but this is the only one I've seen with a panel on the side that lists it right before your eyes, and allows you to click on any command you see there and have it instantly filled in on the current prompt line for revision or re-execution.
Pro Tray icon
Application can be minimized or closed to a tray icon to free up taskbar real estate during background operations.
Pro Wake-on-LAN support
Offers the ability to send a properly formatted "wake-up" packet to a device in the event that it is powered off so that a remote connection can be established.
Con Can not save passwords
Anyway, you can use "PuTTYgen" to generate a key pair, then use "Pageant" to do a password-less SSH remote login.
Con Lacks features
It is JUST an SSH client. There are many other options with built in X-servers, Multitabbing, etc.
Con Ugly design, too simple
Looks very dated. Does the basic functions very well, but not much more.
Con Only one session
Cannot open a second session in the same window.
Con No global settings
If you want to change a setting for all your connections, you'd have to do it individually.
Con Organizing sessions
Does not have features for organizing session connections (like folders). If you have 5-10 connections that's fine. But if there are 30-50 connections - that becomes a nightmare.
Con Tedious logging/tracing
Its tedious to set up logging and tracing (e.g. for serial connections).