The "Speed Telly Bridge Mod" for Minecraft 1.8.9 refers to a set of modifications—some educational and some automated—designed to master or automate Telly Bridging
Given these clues, the most coherent interpretation is: Finding the best bridge mode configuration for a “Speedtouch” (Thomson/Alcatel-Lucent) router model 189, using modified firmware.
The default config.json is slow. Here is the verified best configuration for Mod 189, focusing on speed and stability.
Users report that the "best" version of Mod 189 yields a 40% improvement in data clarity for older fax-over-voice systems and dramatically cleaner audio for radio remotes.