I have a project to enable the internal network. The objects are
1. HK and NT can share the same VLAN 10, 15 and 20
2. the department (IT, account,...) with in the same segment but they are sitting in different location.
3. the bandwidth of WAN is 20M metroNet.
Detail please find the attached file
1. How to config the router and switch so that the VLAN can be in different location but they are in the same segment?
2. If I build the second WAN for load sharing, which spanning-tree should be better to implement? e.g. PVST, PVST+, MST, CST ... etc
if routers are involved I would use L2TPv3 per vlan l2 transport.
This allows you to transport frames inside ip packets.
Load balancing and redundancy would be provided by L3 ip routing.
using vlan-based you can use L2TPv3 to join only specific vlan(s) and you use IP routing for all the other ip subnets.
the link router-core switch is a L2 trunk where one vlan or some vlans are taken by L2TPv3 for carrying over WAN and the others are routed.
what is nice on the router side is that you can decide per Vlan subinterface if the vlan is routed ( ip address ...) or it is L2 transported ( no ip address xconnect command)
L2TPv3 should be supported from 2811 and better routers.
2) you can use rapid-PVST but also BPDU frames are carried into ip packets by L2TPv3.
Hope to help