This work focuses on linear packet combining (coding) strategies for bulk content data distribution in packet-switching networks and their effects on transmission cost. Two representative classes of codes are LT codes and coding with generations (hyperblocks). We design and analyze the performance of these codes. We show that employing coding such as LT codes with optimized degree distribution can increase the efficiency of a simultaneous service to heterogeneous users. And we propose random annex codes based on coding with generations that proves to effectively reduce transmission redundancy by introducing overlaps between generations.