Getting VLAN Stats using SNMP

Hello,

I have throuble getting VLAN stats on a Catalyst 6509 using Supervisor Engine 720 (Cisco IOS 12.2(18)SXD6)

I can get vlan data from:

ifTable ifXTable cseL3VlanStatsTable smonVlanIdStatsTable

related to the data showed in ifXTable/ifTable as "Routed VLANs"; and data showed on smonVlanIdStatsTable is somehow related to the data showed in ifXTable/ifTable as "Unrouted VLANs".

I use the expression "somehow related", because the shape of the graph obtained from the collected data from both tables is almost the same, but does not have the exact data.

One of my switches shows on cseL3VlanStatsTable "0" on all VLANs (I mean the counters are not incremented), but on ifXTable it shows a little traffic on this VLAN but IS NOT "0".

My Questions:

1. What is the exact difference between the data from "Unrouted VLANs" with "Routed VLANs" ?
2. What is the correct SNMP source to get data from ?
3. Is correct to said that the total throughut on a VLAN is routed data plus unrouted data ?
4. Anyone can explain me how can I understand the data on cseL3VlanStatsTable (some rows has "entityId.vlanId" form but others has "entityId.entityId.vlanId" and shows only data on one column) ?

I will really appretiate your help Thanks in advance, Alejandro