Welcome!

Cloud Security Authors: Zakia Bouachraoui, Elizabeth White, Liz McMillan, Pat Romanski, Yeshim Deniz

Related Topics: Cloud Security, Containers Expo Blog, @CloudExpo

Cloud Security: Article

Control the Flow for Security | @CloudExpo #Cloud

Why is TCP/IP great for networking but problematic for security?

TCP/IP connectivity starts with a DNS look-up so that Endpoint A, seeking to establish a connection to Endpoint B, can determine B's IP address. Not knowing when a connection request may be coming, Endpoint B has to continually listen for the arrival of such requests. Not even knowing who the requester is, Endpoint B must respond to the connection request to establish a TCP connection. Only then can Endpoint B seek more information from Endpoint A to try to establish its identity, authorization, and trust.

This basic architecture has fueled hugely scalable TCP/IP networking. The problem is, it requires:

  • Servers to be heavily advertised (DNS)
  • Continual network connectivity
  • Servers to expose themselves to unknown users and devices by responding to TCP requests.

If you have a desire to be as susceptible as possible to network-based attacks, and to be fooled by anyone who has stolen credentials from an authorized user, this is the perfect formula.

Server enforced authorization leave servers vulnerable
To defend themselves, enterprises have tried to limit authorization, usually by mapping employees and other users into Active Directory Groups that define the applications they are allowed to access. The problems, from the standpoint of protection against network-based attacks, are:

  • Stolen credentials can still fool the system if based simply on username/password
  • Servers must engage with the prospective user - establish a TCP connection and then probably a TLS connection - before enough information can be obtained to determine whether the user is authorized or not.

A lot of bad things can happen in that time frame, including SQL injection, OS or server vulnerability exploitation, connection hijacking. It leads to a lot of closed barn door situations where the horse has already escaped.

Speed bumps like firewalls and VPNs and NAC don't slow the attacks
Because of that, over the years, enterprise IT professionals have tried to put controls in place to create "speed bumps" in the network to slow down or stop attackers. The most common of these "speed bumps" are firewalls, VPNs, ACLs, and VLANs.

Network Address Translation (NAT) has been used to create enterprises networks that operate solely in their own private address space, which also enables the deployment of internal DNS servers for internal applications.

Commonly, they are deployed at the traditional perimeter: the LAN/WAN boundary. This means they are mostly about controlling access to remote users. In this case, deployments have been problematic:

  • Tunneled VPN access provides broad LAN connectivity. Creating and maintaining ACLs to limit such access is complex, difficult to maintain, and still results in a large attack surface as the external user must be connected to basic corporate network services (such as DNS, DHCP, software update, and system monitoring).
  • Through phishing and other techniques, attackers have now compromised systems within the internal corporate network, effectively parachuting "behind" the perimeter defenses, rendering them useless.

An attempt to address these realities have been made via Network Access Control (NAC).

When fully deployed, NAC moves the authentication process into the network as a way to prevent unauthorized users from ever seeing or connecting to servers for which they are not authorized to access. NAC is a very promising tool, but still suffers from some unfortunate realities.

NAC can be complex to deploy. For that reason, the granularity of a NAC decision is often just to put an authorized user on one of three different networks (VLANs) - internal corporate network, guest network, quarantine network (used to update software).

To execute greater granularity requires the configuration and maintenance of a complex set of Access Control Lists (ACLs), which are basically a stack of IP address/port white list and black list rules. You could, for instance, limit user A on IPA from connecting to anything but servers B, C, and D of IPB, IPC, and IPD respectively. But, as you can probably imagine, trying to configure this list for all users for all servers for all circumstances is untenable.

The expanding enterprise "perimeter" promises more complexity, less security
There is an even bigger issue today that affects the viability of all these network "speed bump" approaches to security. Where do you put the speed bumps? The assumption with all of these controls is that the enterprise owns and controls the network path to the servers they want to protect. That was a great 1992 assumption. Maybe even 2002. In those days, pretty much all enterprise applications were run from within the enterprise network, accessed by users who were either local or backhauled over the corporate WAN to access the applications.

Is that true now?

Many apps have moved to SaaS or to Cloud Service Providers. Many companies are "untethering" their remote sites and de-commissioning their traditional MPLS or site-to-site VPNs. There is also a growing trend towards wireless networks bought as-a-service and even Layer 2 switches in the cloud. As these trends gain greater momentum, just where would enterprises "plug-in" these network-based "speed-bumps?"

Software Defined Perimeters (SDP): secure, simple
The technology called Software Defined Perimeters (SDP) has been created to address all of the issues cited above. SDP does not attempt to regulate traffic at the network level. It operates at the TCP level, which means it can be deployed anywhere and is transparent to network-level issues such as addressing, ownership, changing topologies, etc. Since data can't flow unless a TCP connection is established, SDP enables an enterprise to completely control who gets to connect to what over their entire extended enterprise network.

In SDP, applications, services, and servers are isolated from users by an SDP Gateway, which is a dynamically configured TCP Gateway. The Gateway rejects all traffic sent to protected servers unless users and endpoints are "pre-approved" by a third-party arbitrator. This third-party role is played by the SDP Controller. Endpoints desiring connectivity to a destination protected by an SDP Gateway don't bother to send a connection request to that destination. Instead they "apply" for connectivity to the SDP Controller, who determines if they are trusted or not.

Trust verification involves device authentication, user authentication, and a set of context-based information that will continue to expand over time - location, BYOD vs. managed device, software posture, software integrity, and more. The goal is to evaluate overall trust as much as possible before allowing connectivity. If satisfied, the SDP Gateway dynamically configures the TCP Gateways to allow connectivity. The systems isolated and protected by the SDP gateways are then never exposed to:

  • Attackers who have stolen credentials
  • Unauthorized systems that may intend to exploit server or application vulnerabilities
  • Successful spear phishers trying to move laterally in a persistent search for access to sensitive data
  • Bad guys who, failing everything else, just want to deny service to others via bandwidth or resource starvation attacks

SDP Controllers and Gateways are software entities and can be deployed with no topological restriction. Thus SDP provides a powerful tool for enterprises to completely control the flow, no matter where the application is (internal or cloud), who the user is (employee or non-employee), or what the device is (managed or BYOD).

More Stories By Mark Hoover

Mark Hoover is CEO of Vidder Security. He has been involved in the technology and market development of security and networking technologies over a period of almost 30 years, including Firewalls, VPNs, IP routing, ATM, Gigabit Ethernet Switching, and load balancers.

Most recently, he has been a Venture Partner at Woodside Fund for two years. Prior to that he was the president of Acuitive, a strategic marketing consulting firm that helped define product and market strategies for start-ups, including Brocade, Alteon Websystems, Netscreen, Maverick Semiconductor, Redline Networks, and many others. He started his career at AT&T Bell Labs and moved to SynOptics/Bay Networks before founding Acuitive.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


IoT & Smart Cities Stories
The challenges of aggregating data from consumer-oriented devices, such as wearable technologies and smart thermostats, are fairly well-understood. However, there are a new set of challenges for IoT devices that generate megabytes or gigabytes of data per second. Certainly, the infrastructure will have to change, as those volumes of data will likely overwhelm the available bandwidth for aggregating the data into a central repository. Ochandarena discusses a whole new way to think about your next...
DXWorldEXPO LLC announced today that Big Data Federation to Exhibit at the 22nd International CloudEXPO, colocated with DevOpsSUMMIT and DXWorldEXPO, November 12-13, 2018 in New York City. Big Data Federation, Inc. develops and applies artificial intelligence to predict financial and economic events that matter. The company uncovers patterns and precise drivers of performance and outcomes with the aid of machine-learning algorithms, big data, and fundamental analysis. Their products are deployed...
Dynatrace is an application performance management software company with products for the information technology departments and digital business owners of medium and large businesses. Building the Future of Monitoring with Artificial Intelligence. Today we can collect lots and lots of performance data. We build beautiful dashboards and even have fancy query languages to access and transform the data. Still performance data is a secret language only a couple of people understand. The more busine...
All in Mobile is a place where we continually maximize their impact by fostering understanding, empathy, insights, creativity and joy. They believe that a truly useful and desirable mobile app doesn't need the brightest idea or the most advanced technology. A great product begins with understanding people. It's easy to think that customers will love your app, but can you justify it? They make sure your final app is something that users truly want and need. The only way to do this is by ...
CloudEXPO | DevOpsSUMMIT | DXWorldEXPO are the world's most influential, independent events where Cloud Computing was coined and where technology buyers and vendors meet to experience and discuss the big picture of Digital Transformation and all of the strategies, tactics, and tools they need to realize their goals. Sponsors of DXWorldEXPO | CloudEXPO benefit from unmatched branding, profile building and lead generation opportunities.
Digital Transformation and Disruption, Amazon Style - What You Can Learn. Chris Kocher is a co-founder of Grey Heron, a management and strategic marketing consulting firm. He has 25+ years in both strategic and hands-on operating experience helping executives and investors build revenues and shareholder value. He has consulted with over 130 companies on innovating with new business models, product strategies and monetization. Chris has held management positions at HP and Symantec in addition to ...
Cell networks have the advantage of long-range communications, reaching an estimated 90% of the world. But cell networks such as 2G, 3G and LTE consume lots of power and were designed for connecting people. They are not optimized for low- or battery-powered devices or for IoT applications with infrequently transmitted data. Cell IoT modules that support narrow-band IoT and 4G cell networks will enable cell connectivity, device management, and app enablement for low-power wide-area network IoT. B...
The hierarchical architecture that distributes "compute" within the network specially at the edge can enable new services by harnessing emerging technologies. But Edge-Compute comes at increased cost that needs to be managed and potentially augmented by creative architecture solutions as there will always a catching-up with the capacity demands. Processing power in smartphones has enhanced YoY and there is increasingly spare compute capacity that can be potentially pooled. Uber has successfully ...
SYS-CON Events announced today that CrowdReviews.com has been named “Media Sponsor” of SYS-CON's 22nd International Cloud Expo, which will take place on June 5–7, 2018, at the Javits Center in New York City, NY. CrowdReviews.com is a transparent online platform for determining which products and services are the best based on the opinion of the crowd. The crowd consists of Internet users that have experienced products and services first-hand and have an interest in letting other potential buye...
When talking IoT we often focus on the devices, the sensors, the hardware itself. The new smart appliances, the new smart or self-driving cars (which are amalgamations of many ‘things'). When we are looking at the world of IoT, we should take a step back, look at the big picture. What value are these devices providing. IoT is not about the devices, its about the data consumed and generated. The devices are tools, mechanisms, conduits. This paper discusses the considerations when dealing with the...