Private Tangles, Transparency, and Potential Risks

It is important to stress that removing the need for any kind of coordinator remains our top research priority for the foreseeable future. But while the network is still reliant on a coordinator, there are some far-reaching consequences to making an open source coordinator available, both positive and negative.

The positive outcomes are increased transparency, increased security and wider adoption, due to greater oversight of the code. Open sourcing also allows for the creation of private tangles; a request we have seen time and time again from businesses and academic researchers looking into the Tangle. Enabling interested third parties to fully-replicate the Tangle on their own will enhance understanding, improve security and increase adoption of the public tangle in the future. Instructions for setting up a private tangle can be found here: https://github.com/iotaledger/compass/blob/master/docs/HOWTO_private_tangle.md

However, if multiple coordinators can now sign and publish milestones on mainnet, IOTA users must choose which coordinator to follow. Different coordinators would quickly create incompatible branches, resulting in what would essentially be a hard fork. Or, to put it simply: a single coordinator can only confirm transactions on a single branch. Furthermore, since addresses should only be used once, spending from the same address into different branches would mean that the address has been reused. As every IOTA user should know, reusing an address lowers security exponentially and should be avoided. It is therefore extremely important that IOTA users choose one coordinator and stick with it, to ensure the security of their tokens.

Given the potential risks involved, it is important that making this coordinator publicly available does not create any problems for ordinary users. For the time being, the IOTA Foundation will continue to run a coordinator at an address that is hard-coded into IRI (link to source). This will ensure that ordinary users’ transactions do not “accidentally” end up in forked branches and/or become susceptible to double spend attacks by virtue of having unwittingly referenced a non-standard (i.e. non-IOTA Foundation) coordinator milestone. Since the vast majority of exchanges, public nodes and users follow the official IOTA Foundation coordinator, we strongly recommend that others continue to do the same as well, at least until we are ready for a coordinator-free Tangle.

The current approach to achieving a Coo-free Tangle has been outlined in the previous posts in this series. We will continue to provide regular updates about Coordicide as progress is made.