Due to some hardware differences, the Series 1600/24xx/4000/8000 switches cannot be used directly in a mesh environment with Series 5300XL switches. Series 5300XL switches need to emulate the operation of Series 1600/24xx/4000/8000 switches in order to have a heterogeneous mesh working properly. Meshing backward-compatibility feature allows Series 5300XL switches to operate in a compatible mode in which the operation of Series 1600/24xx/4000/8000 switches are emulated. When backward-compatibility is enabled, meshing software will establish connections with Series 1600/24xx/4000/8000 switches and emulate their operation. When backward-compatibility disabled, Series 1600/24xx/4000/8000 switches in the mesh will be ignored by the Series 5300XL switches.