The index of map, which are defined by system and user.
The index of system defined map is 1 to 9.
System defined map-name/map-index pairs like this:
Map-index Map-name
1 dot1p-dp
2 dot1p-dscp
3 dot1p-lp
4 dscp-dot1p
5 dscp-dp
6 dscp-dscp
7 dscp-lp
8 exp-dp
9 exp-lp