1. Address Resolution Issues Induced by VPN-oriented Cloud Service
Ning So
Linda Dunbar
80th IETF Prague Czech

2. What Is VPN-o-CS
VPN-Oriented Cloud Services are the extensions to the existing L2 and L3 VPN services into cloud data centers and to control the virtual resources sharing functions
Strictly maintaining the secure, reliable, and logical isolation characteristics of VPN
Making the data center resources as additional attributes to VPNs
Allowing end-to-end VPN-based service management
VPN having the control on how and what data center resources to be associated with the VPN
VPN-oriented Cloud Service is for those VPN customers who want to offload some dedicated user data center operations to the shared cloud centers.
80th IETF Prague Czech

3. Address Issues Induced by VPN-o-CS
Traditional VPN’s end points are Access routers at customer premises. All the hosts belonging to a VPN are behind the access routers.  VPN hosts are hidden from VPN service providers
When VMs in Data Centers are attached to a VPN, VMs belonging to the VPN will be instantiated to the VMs in Data Center(s).  VPN attached hosts/VMs are exposed to VPN service providers.
There can be a lot of those hosts associated with various VPNs.
For any given VPN, the associated VMs could belong to one or multiple subnets, and their IP addresses could be pre-configured or dynamically assigned.
Address Resolution for those VPN hosts is critical to VPN-oriented Cloud Services
80th IETF Prague Czech

4. Address Issues Induced by VPN-o-CS
When VPN attached VMs resides in different data centers, for example, some in provider’s shared data centers and some in client’s dedicated data centers, ARP/ND has to go across WAN
When a host need to forward a data frame to another host within one VLAN:
Host A send ARP/ND to Host B to find the proper MAC address
If no action is taken, all the broadcast messages will go across WAN.
Creating extra data traffic across WAN.
80th IETF Prague Czech

5. Next Steps Continue research the problem. Welcome the feedbacks
A draft will be prepared to present at next IETF
80th IETF Prague Czech