Which never seemed to find wide, mature use.
Service Location Protocol: RFC 2608
RSerPool: RFCs 5351-6
It's a really interesting pub/sub style IPC. But really it's like a swiss-army knife. CORBA lovers (and haters) will recall IDL, it's used as the description for the interfaces used. IMO the commercial implementations are more feature complete than the open source ones.
If you looked at CORBA in the 1990s and have a sour taste in your mouth, don't hold it against DDS. It's a really great approach. It describes interfaces with a dynamically negiotiated Quality-of-Service among participants. The set of reactions to QoS policy violations effectively create hooks for all of your interesting cases.
IMO DDS works best when all of your participants share a broadcast domain, but it's not necessary to set it up that way.
Corba had service location, and I assume many other predecessors did as well.
Doesn't bother me though, stuff gets reinvented and rediscovered all the time.
The more recent approaches, like linkerd tend to also include ways to easily wrap existing services without changing them, which is a plus.
One or more decades ago, these problems were proposed (and solved?) by IETF working groups. I could believe that linkerd offers some new features not considered by those RFCs. But it would be nice if it were extensions of existing protocols instead.
Having a transparent proxy could offer a level of convenient integration rarely found among disparate internet protocols. Then again, there might be really good reasons why collapsing too many features into one layer is a bad idea.