2013 was definitely the year of overlay virtual networks, with every major networking and virtualization vendor launching a new product or adding significant functionality to an existing one. Here’s a brief overview of what they’re currently offering:

Notes

• The table includes shipping products with publicly-available documentation (VMware NSX is an exception – they still don’t trust us to understand the documentation … but at least you can watch the NSX architecture webinar).
• One can always implement a gateway between an overlay network and physical world with a multi-NIC VM. Those solutions aren’t listed in the Gateways column.
• VMware NSX for multi-hypervisors has bare-metal L2 and L3 gateways, VMware NSX for vSphere has VM-based gateways with in-kernel L2 and L3 packet forwarding.
• Hardware gateways for VMware NSX for multiple hypervisors (using OVSDB protocol) have been announced, but we haven’t seen a GA product yet.
• Multiple vendors have announced hardware NVGRE gateways, no major vendor has shipped one.
• Scalability of Hyper-V depends on the orchestration system. I couldn’t find maximum number of managed hosts supported by SC VMM 2012 – earlier versions support up to 400 hosts.
• I couldn’t find the number of hosts or ports supported by a Contrail controller. Scale-out architecture using controller federation and BGP route reflectors is probably limited by the number of MP-BGP routes supported by the BGP route reflector (Contrail solution uses one VPNv4 host route per VM IP address).

Need help?

If you need help designing your next-generation private or public cloud with overlay virtual networks, get in touch. You’ll also find plenty of details in my virtualization webinars:

• Introduction to Virtual Networking will give you an overview;
• Cloud Computing Networking describes numerous technologies you can use to build virtual networks, and their scalability;
• Virtual Firewalls talks about appliance- and NIC-based virtual firewalls;
• VMware Networking Deep Dive covers the technical details of vSphere’s vSwitch, Nexus 1000V and virtual firewalls (including VSG, vShield App and vGW);
• Overlay Virtual Networking describes emerging technologies that you can use to implement large-scale virtualized environments;
• VMware NSX Architecture webinar is a technical deep dive into NSX architecture;
• VXLAN Technical Deep Dive focuses on VXLAN-based virtual networks and VXLAN gateways.

All webinars are included with the yearly subscription.