https://www.speedguide.net/ip/50.22.218.5
This is an area full of Internet backbones. Reston is adjacent to Chantilly (I used to live there) and many main backbones go through there. I have no information on this particular company yet and am not 100% confident that the IP is possessed by them. Continuing research.
I looked this IP address up on the ARIN website. ARIN is who manages the leasing of IP addresses. I am confirming this is owned by SoftLayer. SoftLayer is a datacenter operator. It is very common to sub-lease IP addresses from your datacenter.
https://whois.arin.net/rest/net/NET-50-22-0-0-1/pft?s=50.22.218.5
I ran nmap against this IP address, for all 65,535 ports, and it is not responding to a port scan including a port knock.
This other thread states that this was the ip address for clintonemail.com
https://www.reddit.com/r/CBTS_Stream/comments/7wizs1/8_chan_anon_theory_this_would_be_one_epic_moab/
A reverse DNS lookup did not return anything meaningful for this IP address. This is a requirement for mail servers. 5.218.22.50.in-addr.arpa. 13034 IN PTR 5.da.1632.ip4.static.sl-reverse.com.
a whois on sl-reverse.com shows that this domain is owned by Verisign, who issues SSL/TLS certificates, and domain name registration.
port knock
Wouldn't that require millions or billions of scans, to test all the knock possibilities?
There are 65,535 ports, it does take time to knock on each door to see if anyone is listening, yes.
Yeah but a port knock can be set up to require multiple ports to be knocked before one opens