Modern 'Infantry Systems' in an Apocalypse War

[ChalkLine]

Most developed nations are implementing or have implemented an 'infantry system'. By this I mean an integrated data and communication system complimenting a (usually) visual sensor rig that is then woven into a combined soldier kit. The Russian 'Ratnik' and the US 'Future Force Warrior' are two representative systems.

However, these systems usually assume that the infantryman using them will have the back up of the vast logistics and communications systems available to modern armies. What is going to happen to those troops' gear in a Twilight War?

What do we have to add to include these vital systems for something like a 'Twilight 2025'?