Visualizing A Zero Trust Architecture

It’s more than just re-branding VPNs and NGFWs

Photo by Petter Lagson on Unsplash

Enterprise Network and Security Architects are faced with sifting through the myriad of Cyber Security Vendors all espousing their ‘Zero Trust’ offerings. Before we get into how to break down each vendor’s offering lets first start by identifying some of the key principles and benefits of a Zero Trust architecture.

  • Establish user identity and authorization prior to access
  • Access to private applications, not access to the network – (no need for VPN)
  • Since no network access is granted, the focus can shift to application level segmentation as opposed to network level segmentation
  • No inbound listeners means applications are invisible to unauthorized users, you can’t attempt to hack or brute force what you can not even see

So how should one go about visualizing what a security vendor offering actually looks like in order to see if a vendor solution really walks the zero trust walk? I’m going to introduce two scenarios which should help easily draw the distinctions between a re-branded VPN solution and a real zero trust offering

Traditional VPN

Lets picture a scenario where your Security Vendor Sales Rep comes to visit you. He or she checks in at the front reception desk, is given a badge and then escorted to a conference room. On the way to the conference room they can easily survey how many floors are in the building, where there are individual offices, media/printing rooms, open floor plan seating areas, telecom equipment closets and maybe even where the corporate Data Center server room is. If your vendor rep leaves the conference room they could hypothetically walk up and down the hall where they can jiggle the door handles of any office door they see, scan the visible content on whiteboards or on top of desks in the open floor plan seating areas for sensitive information and strike up casual conversations with anyone in any area they can manage to roam through. This is akin to level of trust provided when giving network level access to a user via a traditional VPN. Instead of the fictitious Sales Rep, imagine that this was a malware infected endpoint brought onto the network by one of your remote employees, a contractor or other 3rd party.

Zero Trust

In this model the same Security Vendor Sales Rep visits and checks in at the front desk to get their badge. This time the Rep only sees one door, the door to the conference room. There are no floors, no visbile office doors, media/printing rooms, open seating areas or telecom equipment closet doors. Only the door to the conference room appears as this is the only thing that your Rep is authorized to see or access. There is no hallway to walk down, no office doors to attempt to pry open and no visibility of the internal environment whatsoever. This is more like what access via a zero trust solution should look like.

To take this a bit further, a security vendor might still say that they can support the objectives of the Zero Trust scenario described above. What are some key red flags to look out for to ensure that this isn’t just a rebranded VPN or NGFW solution?

If a prospective security vendor says they meet the objectives of a Zero Trust implementation, but uses language like ‘perimeter’, ‘micro-perimeter’, ‘use your existing NGFW as a network segmentation gateway’, ‘verify and never trust anything ON your network’, or ‘there is no need to rip and replace your existing network appliances’ be very wary that this is likely just a perpetuation of a previous remote access model and not truly architecting for Zero Trust.

Disclaimer: The views expressed here are my own and do not necessarily reflect the views of my employer Zscaler, Inc.