Implementing an "ad-hoc-like network of payment channels" on top of Bitcoin network? If we define an ad-hoc network as follows:


  "An ad hoc network is a network that is composed of individual devices
  communicating with each other directly." [1]


ad-hoc networks do not rely on routers or access points (as a point of failure) to avoid moving towards centralization. In case of using routers or access point, some kind of centralization is inherent. 

With this definition of decentralization, can we implement an ad-hoc-like network between users connected by payment channels such that similar to ad-hoc network, they do not use any router to find and communicate each other?

Please note that I used term of ad-hoc-like network (instead of saying ad-hoc network) just to say that the target is removing any pre-existing infrastructure, such as routers from communications between users similar to an ad-hoc network.



[1] https://www.techopedia.com/definition/5868/ad-hoc-network
This is absolutely possible. The negotiation between the payment-channel participants can happen over the ad-hoc network.

However, each participant must still run a fully validating node at all times when he/she has an open channel-state, to be able to react to cheating counterparties. This validating full node may receive its updates over the ad-hoc network as well, but must be in consensus with the wider Bitcoin network.

If the ad-hoc network prevents Bitcoin nodes from connecting with other nodes outside of it, this will obviously be a problem.