How a Tap or SPAN Choice Impacts APM
May 22, 2019

Keith Bromley
Ixia

Share this

For application performance monitoring (APM), many in IT tend to focus a significant amount of their time on the tool that performs the analysis. Unfortunately for them, the battle is won or lost at the data access level. If you don’t have the right data, you can’t fix the problem correctly.

This viewpoint is backed up by an APMdigest post back in August where Jim Frey cited some critical survey research. The research showed that "26% reported that their biggest challenge with incident response is that data exists, but they can’t access or analyze it easily." Key point – you need access to the right data at the right time to solve your problems.

This begs the question — how do I get the right data access?

The best source of data is from a network tap. A tap makes a complete copy of ALL the data passing through it. It is a passive device, so it does not alter any of the data and has a negligible effect on transmission time.

Taps are great because they are "set and forget." You simply plug the device into the network with a one-time disruption and you are done. No programming is required. Best of all, you can place taps anywhere in the network that you need data from — ingress, egress, remote offices, etc.

The one drawback to using taps is that if you install lots of them (which you will want to do), the amount of data feeds can overload the input ports to your APM tools. However, this issue is easily resolved by installing a network packet broker (NPB) to aggregate the data from the taps, filter the data as necessary, and then send that data on to the APM tool. This eliminates the overcrowding of the data ports on your APM tool.

An alternative to a tap is to use a mirroring port (also referred to as a SPAN port) off of your network switches. However, this is not recommended. One reason is that these ports are active devices, i.e. they can materially change data packet characteristics as the packets flow through the device. This is especially important when using data from these ports to diagnose problems.

In addition, bad packets (i.e. malformed packets) are dropped by the SPAN port. This ends up giving you a "digital view" of the situation, i.e. everything is fine and then there is a problem. Missing packets that could show degradation prior to data loss (which could have been useful to create a quicker diagnosis) is missing, along with any context as to what was happening before the problem began.

In the end, optimum data capture can be achieved using a tap and NPB. This results in a faster mean time to repair (MTTR).

Keith Bromley is Senior Manager, Solutions Marketing at Ixia Solutions Group, a Keysight Technologies business
Share this

The Latest

August 22, 2019

Recent EMA research explored the state of ESM. One of the many conclusions is that ESM is mainstream. Fully 87% have some level of ESM deployment. Not surprisingly, there is a significant divide between mature and relatively new deployments in terms of benefits derived, use of AI and automation, adoption levels, and number of non-IT areas being served from established ITSM implementations ...

August 21, 2019

For the first time, a majority of companies are putting mission critical apps in the cloud, according to the latest report by Cloud Foundry Foundation ...

August 20, 2019

The cloud continues to transform IT in every industry. But in order to migrate to the cloud, embrace these new technologies and truly evolve their business, organizations need an underlying network that can support digital transformation ...

August 19, 2019

One common infrastructure challenge arises with virtual private networks (VPNs). VPNs have long been relied upon to deliver the network connectivity and security enterprises required at a price they could afford. Organizations still routinely turn to them to provide internal and trusted third-parties with "secure" remote access to isolated networks. However, with the rise in mobile, IoT, multi- and hybrid-cloud, as well as edge computing, traditional enterprise perimeters are extending and becoming blurred ...

August 15, 2019

The configuration management database (CMDB), along with its more federated companion, the configuration management system (CMS), has been bathed in a deluge of negative opinions from all fronts — industry experts, vendors, and IT professionals. But from what recent EMA research on analytics, ITSM performance and other areas is indicating, those negative views seem to be missing out on a real undercurrent of truth — that CMDB/CMS alignments, whatever their defects, strongly skew to success in terms of overall IT progressiveness and effectiveness ...

August 14, 2019

The on-demand economy has transformed the way we move around, eat, learn, travel and connect at a massive scale. However, with disruption and big aspirations comes big, complex challenges. To take these challenges head-on, on-demand economy companies are finding new ways to deliver their services and products to an audience with ever-increasing expectations, and that's what we'll look at in this blog ...

August 13, 2019

To thrive in today's highly competitive digital business landscape, organizations must harness their "digital DNA." In other words, they need to connect all of their systems and databases — including various business applications, devices, big data and any instances of IoT and hybrid cloud environments — so they're accessible and actionable. By integrating all existing components and new technologies, organizations can gain a comprehensive, trusted view of their business functions, thereby enabling more agile deployment processes and ensuring scalable growth and relevance over the long-term ...

August 12, 2019

Advancements in technology innovation are happening so quickly, the decision of where and when to transform can be a moving target for businesses. When done well, digital transformation improves the customer experience while optimizing operational efficiency. To get there, enterprises must encourage experimentation to overcome organizational obstacles. In other words ...

August 08, 2019

IoT adoption is growing rapidly, and respondents believe 30% of their company’s revenue two years from now will be due to IoT, according to the new IoT Signals report from Microsoft Corp ...

August 07, 2019

It's been all over the news the last few months. After two fatal crashes, Boeing was forced to ground its 737. The doomed model is now undergoing extensive testing to get it back into service and production. Large organizations often tell stakeholders that even though all software goes through extensive testing, this type of thing “just happens.” But that is exactly the problem. While the human component of application development and testing won't go away, it can be eased and supplemented by far more efficient and automated methods to proactively determine software health and identify flaws ...