Couldn't you use a DDNS (Dynamic DNS) service, like OpenDNS or NoIP?
Instead of having to remember whatever is the current IP address for the
remote host, you just remember the one hostname for it. If you don't
have a static IP address at the remote, you can run their DNS updater
client on the remote host. That updates your DDNS account with the
current IP address of the remote host. An update is sent every 28 days
(helps to keep-alive a free DDNS account) or whenever the IP address
changes on the client's host or when you do it manually for some reason.
That way, you don't have to remember IP addresses or worry about when
they change. Just use the same hostname, like sbremote-1, for that
remote host's name which is always the same hostname.
Logmein went to a payware service. No free account. Teamviewer allows
a free account only for personal use. mikogo is free whether for
personal or business use. They all work by having their client make an
outbound connection to their server to query if there is a pending
request to connect to that host. That eliminates problems with
firewalls which usually block unsolicited inbound connections. Since
the client connection is outbound via HTTP[S], the firewall lets that
pass without interference or prompting. The two endpoints use the
server only to find each other after which the server isn't involved.
The two endpoints connect to each other after the handshake. Traffic
coming into the remote host is over the same HTTP[S] connection that was
originally an outbound connection so the firewall is still not in the
way. I believe their software encrypts the traffic; else, every hop
between the endpoints in the route between them could sniff the traffic.
They can still see what are the endpoints but not the content of the
traffic.
I used Logmein for awhile but quit when they yanked the free accounts.
Teamviewer is nice but only for personal use. mikogo is free for any
use with limitations, like only 2 endpoints involved in the session (no
sharing with multiple participants). With VNC or its variants, I had to
configure the client and server, punch a hole in the software firewall
on the remote host and also in the firewall in the remote host's router
along with defining port forwarding in the router. When I did that way
back is when I learned of using DDNS so I didn't have to worry about a
changing IP address or remember what it was at that time.
When I visited the URL you gave for uvnc2me (or for
uvnc.com), that site
doesn't want me to visit there while protected from ads or tracking. It
bitches that I have an adblocker and shoves an interstitial bitch page
at me with a countdown timer that makes me wait for 10 seconds before it
returns to the original page. What assholes. Yep, I will continue
using an adblocker (uBlock Origin + uMatrix) and usually when a page
refuses to provide its content because it detect adblocking is when I
leave that site. It's their choice to block content if they sense that
I'm using an adblocker. It's my choice not to visit their ad polluted
or tracking enabled site.
You never mentioned what OS is on the endpoint hosts. The web access
method doesn't care on the local end; however, you need to run their
client on the remote host. Mikogo only supports Windows (7 and up).
Looks like Windows (7+) and OS/x (10.7+) for Logmein. Teamviewer lists
Windows, Mac, Linux, ChromeOS, Android, and iOS. According to
https://en.wikipedia.org/wiki/UltraVNC, UVNC (UltraVNC) only supports
Windows. I wasn't going to bother with UVNC's site and their bitching
about me using an adblocker. I guess if I were to reconsider using a
VNC variant again, I'd want one where they had a server (listening
process) that could run on Windows, Linux (which includes OS/X since
that's Linux). Android and iOS would be nice but I have yet needed to
remotely troubleshoot or use a smartphone or tablet. Since UltraVNC is
limited to the Windows platform, wouldn't their uvnc2me product also be
limited to only Windows?
You can see a list of remote desktop software at:
https://en.wikipedia.org/wiki/Comparison_of_remote_desktop_software#Operating_system_support
That should help in deciding what to use for what OS platforms you want
to support.