A steel messenger is a stranded steel cable that acts lashing wire. Steel messenger strand consists. Aerial Cable Installation Deploying fiber above ground on poles or towers removes the need for underground digging and is particularly useful when the ground is uneven, rocky or both. The laying of these two types of fiber optics is also. The FIBERLIGN Suspension uses a combination of structural reinforcing rods (SRR), outer rods, housing halves, and resilient inserts to reduce compression, clamping, and bending stresses on OPGW and the optical fibers within it. SRR and outer rods cannot be reused.