When number is used for BGP community list name, the number has special meanings. Community list number in the range from 1 and 99 is standard community list. Community list number in the range from 100 to 199 is expanded community list. These community lists are called as numbered community lists. On the other hand normal community lists is called as named community lists.
This command defines a new community list. <1-99> is standard community list number. Community list name within this range defines standard community list. When community is empty it matches to any routes.
This command defines a new community list. <100-199> is expanded community list number. Community list name within this range defines expanded community list.
When community list type is not specifed, the community list type is automatically detected. If community can be compiled into communities attribute, the community list is defined as a standard community list. Otherwise it is defined as an expanded community list. This feature is left for backward compability. Use of this feature is not recommended.