bgp-overview: Extend section on network interconnect
Apply some suggested additions from
@@ -144,12 +144,16 @@ distribute traffic among the Nodes.
A future enhancement needs to be filed to pursue this integration in more
detail.
-### Virtual Network Interconnect
+### Virtual Network Interconnect and Hybrid Cloud
The Pod network is by default an isolated virtual network. There is sometimes
a desire to interconnect multiple virtual networks together. This could be
between multiple Kubernetes clusters, but it doesn't have to be the case.
+BGP, specifically MP-BGP, is commonly used as a signaling protocol, together
+with other data planes technologies like MPLS and VXLAN to interconnect virtual
+network at L2 or L3.
+
BGP EVPN (Ethernet VPN, or Virtual Private Network) is a BGP technology that is
discussed in the context of this use case. BGP EVPN can be used to advertise
MAC addresses and IP-MAC address bindings. BGP EVPN is not a full solution to
@@ -157,6 +161,10 @@ this use case by itself, as it is a technology that can help implement part of
the control plane. There are more details that must be explored, including
what the data plane looks like between the two clusters.
+BGP and MPLS is heavily used in the Telco area, and by the Cloud providers to
+interconnect their facilities to the Cloud, i.e. [AWS Direct
+connect](https://d1.awsstatic.com/whitepapers/Networking/integrating-aws-with-multiprotocol-label-switching.pdf).
+
This is a significantly non-trivial effort. Future enhancements are needed to
discuss this in much more detail.
