The Wall was a space defense system protecting Fortress Republic.
The Fortress Republic protocol was activated by Exarch Jonah Levin in 1 October 3135, and in a short time later gave light of a new technology dubbed "The Wall". The Wall only worked around a determined ring of worlds slightly larger than the Republic's Prefecture X. Any JumpShip attempting to cross it would misjump or bounce back in a mangled state, with the crew crippled or combined with the ship, like Coordinator's Theodore Kurita's WarShip Pride of Kurita.
In 3149, Devlin Stone would turn off the Wall, allowing the Republic troops to leave the Fortress space, and the outsider states to invade the Fortress... but when the Capellan Confederation and Clan Wolf JumpShips attempted to attain Terra, both bounced. This proved that the Wall was still active, only now around the Terran system.
Any JumpShip that has appeared to complete the transit have not been seen since. It is unknown if they were captured by Republic forces, misjumped or have been totally destroyed. The Wall is a proof about how little is known about hyperspace and Kearny-Fuchida experts are unable to explain how it is possible.
However, it must be noted that the Wall was not a rigid defense; "windows" can be opened, allowing a JumpShip to cross safely, like Julian Davion's JumpShip in 3146. At the end it was revealed that the Wall wasn't really one, but a means to targeting and disrupting emergence waves from ships which jump into its space, but it cannot respond fast enough to ships jumping from a distance of half a light year or less.
- Dragon Rising p. 271
- Shattered Fortress, p. 92
- Shattered Fortress, p. 106
- Shattered Fortress, p. 107
- Shattered Fortress, p. 7
- "Bring the Dawn"
- Children of Kerensky p.145