German version here: https://www.securefever.com/blog/secure-medical-devices-with-vmware-sd-wan-and-nsx-mdtpt

In the last years we have seen a lot of cyber attacks like ransomware, malware, trojaner, etc. within the healthcare sector. In the recent past a ransomware attack to the Irish medical healthcare system (https://www.bbc.com/news/world-europe-57197688) has happened. The main hacking targets are the medical devices like Infusion pumps, Computertomographs (CT), Magnetic resonance imaging (MRT), PACS systems (Picture Archiving and Communication System), etc.

Why medical devices a popular target for hackers?

There are several reasons for this. The medical devices have often security vulnerabilities and the patches are not up-to-date because there is different hardware, special operation and application systems in place. It is not just to think about how can I secure a dedicated Windows or Linux OS version. Hospitals or clinics have to manage a lot of different software and end devices. Medical devices use special protocols like DICOM (Digital Imaging and Communications in Medicine) and often it is not allowed from regulation perspective (i.e. ISO standards, BSI certifications, etc.) to make changes on this appliances.

Another main reason why medical devices are a popular target for hackers is the high cyber security risk. An impact of a attack within the healthcare sector can be really critical. The result can be end in a outage of medical devices, danger for the patient, loss of personal patient data or interruptions within the daily hospital work. The Covid-19 pandemic makes this more real and critical.

What are the use cases for SD-WAN and NSX?

Before I will describe how VMware secures medical devices, I want to provide an overview about the common use cases for VMware SD-WAN and NSX.

VMware SD-WAN optimizes WAN traffic with dynamic path selection. The solution is transport-independent (Broadband, LTE, MPLS), simple to configure and manages and provides a secure overlay (see picture 1). VMware SD-WAN use Dynamic Multi-Path Optimization (DMPO) technology to deliver assured application performance and uniform QoS mechanism across different WAN connections. DMPO has 4 key functionalities - continuous monitoring, dynamic application steering, on-demand remediation and application-aware overlay QoS.

DMPO can improve line quality for locations with two or more connections like MPLS, LTE, leased lines, etc. The WAN optimization is also useful for locations with a single WAN connection.

NSX Software-Defined Networking solution is designed to provide Security, Networking, Automation and Multi-Cloud Connectivity for Virtual Machines, Container and Baremetal Server.

NSX-T provides Networking function with GENEVE Overlay technology to realize switching and routing on a distributed hypervisor level. NSX is capable for Multi-hypervisor support (ESXi, KVM) and has a policy-driven configuration platform. Network services like BGP and OSPF for North-south routing, NAT, Load Balancing, VPN, VRF-LITE, EVPN, Multicast, L2 Bridging and VPN can be implemented with NSX.

Security with Micro-segmentation is the key driver for NSX. The distributed firewall is sitting in front of every VM and east-west security can be realized without dependencies to IP address ranges or VLAN`s technology. A Firewall, Deep-Paket-Inspection (DPI) and Context Engine on every hypervisor are realizing an high performance service defined firewall on L7 stateful firewalling basis. ESXi Hosts don`t need a agent for Micro-Segmentation, the existing ESXi mangement connection is used to push firewall rules.

IDPS (Intrusion Detection and Prevention System) is also possible since NSX-T version 3.x, including a distributed function (see for more details my blog post https://www.securefever.com/blog/nsx-t-30-ids). Other security feature like URL Analyses, Gateway Firewall for North/South Security and third partner vendors security integrations to NSX are as well included.

Multi-cloud networking is also a use case for NSX. This could be between private data centers to design disaster recovery or high availability network and security solutions or for hybrid public cloud connectivity.

Container Networking and Security is another important use case for NSX. This can be achieved with a dedicated NSX NCP Container Plugin or from the recent past with a new VMware created open standard CNI (Container Network Interface) named Antrea.

Check for more detail information about NSX the VMware NSX-T Reference Design guide for NSX-T version 3.x https://communities.vmware.com/docs/DOC-37591 and the NSX-T Security Reference Guide https://communities.vmware.com/t5/VMware-NSX-Documents/NSX-T-Security-Reference-Guide/ta-p/2815645

How can VMware SD-WAN and NSX can help to secure medical devices?

The combination of SD-WAN and NSX makes the whole solution unique. SD-WAN hardware Edge boxes are taking care about the initial access of the medical devices and the secure transport connection to the data center. Within the data center NSX is the feature to secure the medical devices servers independently if it is a virtual machine, bare metal server or container based solution.

The solution is simple to install and operate, all SD-WAN components (hardware and software) will be managed from the SD-WAN Orchestrator. It is flexible, i.e. global policies can be configured. Everything within the data center is software based and it is easy to scale. A NSX Manager cluster is configured for the management and control plane for NSX within the data center.

1. SD-WAN Edge device in front of the medical device

The first access point or default gateway of the medical devices is the Edge SD-WAN hardware component (see picture 2). It is also possible to place a L2 switch or WLAN access controller behind the Edge if you have more medical devices on a area. A firewall on the SD-WAN Edge handles the initial access security and the connections between different medical devices behind the same SD-WAN Edge.

2. Secure transport connection

The SD-WAN Edge will establish a dedicated tunnel to a SD-WAN Edge in the data center. The local area network (LAN) builds the transport network. The VeloCloud Multi-Path Protocol (VCMP) is used to establish an IPSec-secured transport tunnel over port UDP 2426. The SD-WAN Edge in the data center could be also hardware based but the easiest way is to create it on VM-based factor basis. The VM has one WAN interface to establish the IPSec endpoint and one LAN interface to have connection to the medical devices virtual machines or Bare Metal like DICOM or PACS server. If medical devices needs to talk to other medical devices on different SD-WAN Edges the IPSec tunnel can be created also directly without a redirection to the data center Edge.

3. SD-WAN within the Data Center with handover to NSX

If no NSX Overlay (Routing & Switching) is configured within the data center, the existing vSphere Networking implementation (see picture 3) can be used. All NSX security feature can be implemented without a change on the routing and switching area. The VM`s or Bare Metal Server are using the SD-WAN Edge as Gateway. NSX security is independently from the networking infrastructure and the NSX distributed firewall is sitting in front of every VM interface (vnic). This means the traffic can be secured between different VM`s and it doesn`t matter if the virtual machines are part of the same IP range or not.
If NSX Overlay exist a routing connection will be established between the SD-WAN Edges and the NSX Edges (see picture 3). It can be realized via BGP, OSPF or static routing. A NSX gateway firewall can be configured to secure the north-south traffic or the tenant traffic.

4. Operation and Monitoring

The SD-WAN Orchestrator (VCO) is taking care about the configuration and administration of the SD-WAN Edge boxes. The SD-WAN Orchestrator is available as SaaS service or on-premise. The SaaS service is much more easy to implement and administrate. Only “Meta data” will be send from the SD-WAN edge to the Orchestrator (VCO) over a encrypted tunnel for reporting and monitoring purposes. The VCO provides an active monitoring report on its Graphical User Interface using the data received from the Edge devices. Edge devices collect information like source IP address, source MAC address, source client Hostname, network ID, etc. The SD-WAN hardware edges which are placed in front of the medical devices can be activated from a none IT person due to a Zero Touch Provisioning approach (see picture 4). The process is realized in 3 steps. Initial step is that the IT Admin add the Edge to the VCO and creates an activation key. Second step is the device shipment and a email with the activation key from the IT Admin to the onsite person. Last step of the deployment is that the local contact plugs in the device with internet access and activates it with the dedicated key which has been sent via email. Afterwards the IT Admin has access to the Edge and can to further configuration to add the medical device.

The whole solution can be monitored with vRealize Network Insight (vRNI). vRNI can discover flows from physical network devices (routers, switches, firewall), SD-WAN, virtual infrastructure (NSX, vSphere), Containers and Multi-Cloud (AWS, Azure). The tool provides troubleshooting features and helps a lot for security planning. Visibility is also available, see picture 5 with a packet walk from a dedicated source IP to a dedicated destination IP, the path details are very useful.

Summary

The solution is simple to install and operate. SD-WAN and NSX have a lot of automation in place from default and this makes it very flexible and scalable. The key feature of the solutions are:

SD-WAN

• Access protection of the medical devices through MAC authentication.

• No changes are mandatory on the medical device

• Roaming of the devices from one edge to another, no configuration change is mandatory.

• Zero Touch Provision for the edges

• Separation of all ports on an Edge through VLANs.

• Centralized administration.

• Use of global policies for simplified administration.

• Secure transport encryption from the edge to the data center

• Hardware or Software possible (in the data center)

NSX

• Protection within the data center with Distributed Firewall and Microsegmentation at the VM, container or baremetal server level.

• Granular control of access on every VM

• ESXi hosts do not require an agent

• Firewall rules will be moved within the vMotion process.

• Routing instances can be separated

• NSX IDPS (Intrusion Detection Prevention System) with a distributed function available

• Central administration and monitoring

• ESXi hosts at remote sites can be centrally administered with NSX.

There is another brilliant tool named Edge Network Intelligence (formerly Nyansa) which is very interested for the healthcare sector in case of AI-Powered Performance Analytics for Healthcare Networks and Devices. I will create another blog post within the next weeks for this topic.