Solutions for Data Centres

Point-to-point tunnelling protocol (PPtP) is an old and deprecated technique for providing tunnel functionality.

Generic Routing Encapsulation (GRE) was originally developed by Cisco and although it is quite old, there are still useful applications for it. I could use it in a similar manner to a VPN. It can be very handy for connecting discontinuous zones in a datacentre, ignoring the properties of the network connecting the two zones. In many ways this was the first overlay network I used.

Software Defined Networking (SDN) is a term much abused by the sales and marketing people. In its original incarnation using the OpenFlow protocol, it had the potential to uniquely connect nodes together, for specific protocols. In many ways, it provides the circuit switched capability of an old ATM network, to modern packet switched network. OpenFlow has not proved a successful as might have been expected.

Virtual Extensible LAN (VXLAN) uses encapsulation to transport layer 2 frames with 224 VLAN-like tags. It is becoming very common in data centre environments. In VMWare designs, we have NSX, a software defined solution that allows for micro-segmentation and the creation of overlay networks.