[alto] How Data Center Virtualization influence ALTO mechanism.

["Y.J. GU" <[e-mail]>]

Hi all, 
I was thinking about how Data Center Virtualization and Virtual Machine(VM) Migration will influence ALTO mechanism.

Current ALTO Protocol defines clustering of peers according to their IP Addresses. E.g. peers in same subnet will be classified into same PID, and path cost will indicate the cost within and between PIDs, which is also actually based on IP Addresses.

In the current world, peers are partitioned by IP subnet. While considering virtual machines migration, there might be more interesting things to think of.

In Data Center operation, one basic consensus is 'When Virtual Machines move from one site to another, the IP Addresses will not change, so that the existing service connection will not be broken'.  VMs can migrate to arbitrary site, not under the control and knowledge of ISP. For example, some VMs in Data Center A(IP subnet 198.1.1.0) move to Data Center B (IP subnet 210.1.1.0). IP-based, Vms are closer to DC-A. Physically, these VMs are much closer to hosts in DC-B. However things are not so easy, especially considering how these VMs are routed. Current ALTO may give wrong cost ranking.

VMs may migrate under, but not limited to, these situations: 1) to save electricity power, 2) disaster recovery, 3) customer prefer another Data Center, 4) company extension, etc. In the end, the internet will not be a regular world partitioned by IP Addresses.

Does anyone think this is an interesting aspect to study?