check possibilities to benefit from Linkerd

[hpvd]

Is your enhancement request related to a problem? Please describe.

Check if it's possible and worth it on the long run, to make Pulsar even better, easier to use and maintain, more secure and enhance possibilities even further by identifying possibilities (if/where/how) of using a light service mesh (Linkerd)

Describe the solution you'd like

check possibilities to benefit from Linkerd

Linkerd is a very light and fast service mesh.
It makes it easier or even possible to

• establish and maintain secure connection between components and clusters
• brings telemetry (e.g. performance)
• load balancing,
• traffic split for blue green canaries deploys,
• etc.

Technical it's based on a central driven proxy infrastructure (sidecar) using a self-developed micro proxy named "Linkerd2-proxy"

With this, imho it's looking at Linkerd vs the very often used Istio (which uses envoy proxies) it feels a little like looking on Pulsar vs Kafka:
easier to use, has the right high value options, made for speed
https://linkerd.io/2020/12/03/why-linkerd-doesnt-use-envoy/

It's somehow Kubernetes native in the same direction you look for the upcoming function mesh...
https://www.youtube.com/watch?v=Rq8Zfxd8xfU

some highlights from the latest releases:

v2.8 "Multi-Cluster the Kubernetes way"
"connect Kubernetes services across cluster boundaries in a way that's secure, fully transparent to the application, and independent of network topology"
see https://linkerd.io/2020/06/09/announcing-linkerd-2.8/

v2.9 "Zero trust with zero-config, on-by-default mutual TLS"
https://linkerd.io/2020/11/09/announcing-linkerd-2.9/

in general their blog is worth to be looked at https://linkerd.io/blog/

good explanation of how mutual TLS works and why it makes sense:
https://freedomben.medium.com/what-is-mtls-and-how-does-it-work-9dcdbf6c1e41

This issue should just give push to the long/midterm strategy to think about

• if/
• where/
• how

it may be possible for pulsar to benefit from the today technically matured service meshes in general
and especially looking at Linkerd (v2+) because of it's unique goal for "high speed and best security in the most easy way".