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.