Access systems are messy. Wait, let me rephrase that, Poorly planned access systems are messy.  We’ve all seen it happen a thousand times. Someone comes r... Read more

In many small to medium sized companies (and even some fairly large ones), when you need a new piece of software installed on your desktop, you call the IT guy, or put in a trouble ticket, and the IT guy shows up with a DVD or CD, and install... Read more

Introduction Virtually every dynamic site on the Internet these days makes use of a CAPTCHA in some fashion. A CAPTCHA is used to verify that a human is driving the interaction with a particular  function on a site. A CAPTCHA in its simples... Read more

Introduction Earlier this year Google released their time-based one-time password (TOTP) solution named Google Authenticator. A TOTP is a single-use code with a finite lifetime that can be calculated by two parties (client and server) using ... Read more

Introduction It is impossible to enumerate all the scenarios under which CIFS access via or by ARX may be denied. In many cases, denial of access may be the desired behavior and can sometimes be temporary. This article is intended to aid in... Read more

As we hurtle forward through the information age we continue to find ourselves increasingly dependant on the applications upon which we rely. Whether it's your favorite iPhone app or the tools that allow you to do your job, the application... Read more

One time passwords, or OTP, are used (as the name indicates) for a single session or transaction.  The plus side is a more secure deployment, the downside is two-fold—first, most solutions involve a token system, which is costly i... Read more

I started working on an administrator control panel for my previous Small URL Generator Tech Tip (part 1 and part 2) and realized that we probably didn’t want to make our Small URL statistics and controls viewable by everyone. That led me to make... Read more

Security extensions were added to the DNS protocol as a means of countering malicious attacks such as cache poisoning, domain hijacking, and man-in-the-middle attacks.  The extensions are described in detail in RFC 4033 (Introduction an... Read more

A Self IP address is an IP address that you associate with a VLAN, to access hosts in that VLAN. By virtue of its netmask, a self IP address represents an address space, that is, a range of IP addresses spanning the hosts in the VLAN, rather than... Read more

PowerShell is a very extensible scripting language and the fact that it integrates so nicely with iControl means you can do all sorts of fun things with it.  In this tech tip, I'll illustrate how to use just a couple of iControl method... Read more

LDAP is one of the most widely used authentication protocols around today. There are plenty of others, but LDAP is undeniably one of the big ones. It comes as no surprise then that we often hear different questions about using F5 technology with... Read more

SSL encryption as a means of security on the web isn't a new concept. We've talked about it here on DevCentral many times, and it's as pedestrian a concept as a corndog on the boardwalk to most internet users. We've talked about... Read more

SSL encryption on the web is not a new concept to the general population of the internet. Those of us that frequent many websites per week (day, hour, minute, etc.) are quite used to making use of SSL encryption for security purposes. It's an... Read more

What is RADIUS? “Remote Authentication Dial In User Service” or RADIUS is a very mature and widely implemented protocol for exchanging ”Triple A” or “Authentication, Authorization and Accounting” information. RADIUS is a relatively simple,... Read more

In a previous article, I discussed user management and the concepts of user roles.  User roles form half of what we refer to as Administrative Domains.  The second half of Administrative Domains are Configuration Partitions.  ... Read more

iControl is a robust management API that not only encompasses the control of network management objects, but also many other aspects of the system level configuration. This article will discuss the methods used to create and manage all aspects of... Read more

A basic change in internal routing architecture and functionality between BIG-IP 4.x and LTM 9.x has caused some confusion for customers whose v4.x deployment depended on IP forwarding. Here is an explanation of the change, and the new... Read more

RADIUS is very popular authentication method that is being widely used in amongst some of the top service providers around the world, not to mention in deployments ranging from enterprise corporate environments to clustered mail systems and back.... Read more

Client side certificate authentication systems continue to gain popularity in many business verticals.  The ease and reliability of a certificate based system have the potential to save companies time and money through lowered operational... Read more

Customers frequently ask if they can condition their iRule logic on information retrieved real-time from an external source.  In most cases, you really can't. Most external calls are blocked If an external call were to take place inside... Read more

Path Traversal is an attempt to access files and/or directories stored outside web root folder. If successful this could allow malicious users to view content they were not intended to see, execute programs that have lax permissions and were... Read more

Note: Special thanks to the Firepass development team for providing this tip. As IT departments deploy an ever-growing list of mobile devices, secure authentication becomes an even bigger nightmare to keep IT management awake at night. One option... Read more

A fun, but not well known, feature on BIG-IP is the Statistics Profile. This tech tip is the second in a series on how the Statistics Profile and iRules, when working together, can save time, productivity, and your sleep! The Scenario: Imagine... Read more

As the applications being driven by webservers become more and more complex, Applications Developers are always looking for ways to increase efficiency or do away with unneeded processing time. One of the ways that I believe that Applications can... Read more