You can link labs from bases that has research lab level 18 or higher, to a base that has research lab level 20
You need the Subspace Communications technology to achieve that
By linking the labs, your research output at the main lab will sum with all linked ones
Commanders reduce the tech prices by 1% per level
The commanders from each linked lab counts, with this math rule:
sum(linked labs cmdrs.)^0.8 + main lab research cmdr. + research minister
example:
6 linked bases with cmdr. level 5, main base with lvl 10 and minister level 5
sum(30)^0.8 = 15 + 10 + 5 = 30% discount to all techs
There is a cap limit of 80% to avoid free techs