A few solutions worth evaluating, especially w/ what is going on right now with the increased demand to securely support remote work:
1. Zscaler ZPA - closed source but from a market leader
2. Palo Alto - subjective if true zero trust but if you already have PA...
3. Akamai - based on a SDP acquisition which had good tech - not sure what Akamai has done with it
4. NetFoundry - both open source and SaaS options
5. Nebula - strengths for east-west microservices. Open source from Slack.
6. Tailscale - listed above. New but open source.
7. Appgate - closed source but nice implementation of the use cases it targets.
8. Illumio - a more mature version of Nebula; also targeted at east-west.
9. Centrify - closed source but solid option for IAM focused use cases.
10. Perimeter81 - not familiar with it but is well regarded.
11. Cloudflare - relatively new solution but leverages their network nicely
12. Duo - certainly was a nice solution - not sure what Cisco has done with it.
13. ZeroTier - not familiar but adding per comments below
* Edits - added 11-13 per comments below in attempt to make this a more comprehensive list.
1. Zscaler ZPA - closed source but from a market leader
2. Palo Alto - subjective if true zero trust but if you already have PA...
3. Akamai - based on a SDP acquisition which had good tech - not sure what Akamai has done with it
4. NetFoundry - both open source and SaaS options
5. Nebula - strengths for east-west microservices. Open source from Slack.
6. Tailscale - listed above. New but open source.
7. Appgate - closed source but nice implementation of the use cases it targets.
8. Illumio - a more mature version of Nebula; also targeted at east-west.
9. Centrify - closed source but solid option for IAM focused use cases.
10. Perimeter81 - not familiar with it but is well regarded.
11. Cloudflare - relatively new solution but leverages their network nicely
12. Duo - certainly was a nice solution - not sure what Cisco has done with it.
13. ZeroTier - not familiar but adding per comments below
* Edits - added 11-13 per comments below in attempt to make this a more comprehensive list.