Statistics to monitor the traffic on a specific vlan is not supported.
The specific OID which customer was looking for was 1.3.6.1.2.1.2.2.1.10.2052(for vlan 4)
OID name: ifInOctets
Description: The total number of octets received on the interface,including framing characters.
Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ifCounterDiscontinuityTime.
MIB OID for interface vlan is not supported .
An enhancement Wi can be raised in a later release