General – Behavior Of QoS Queues On Cisco IOS

I have been running some QoS tests lately and wanted to share some of my results. Some of this behavior is described in various documentation guides but it’s not really clearly described in one place. I’ll describe what I have found so far in this post.

QoS is only active during congestion. This is well known but it’s not as well known how congestion is detected. the TX ring is used to hold packets before they get transmitted out on an interface. This is a hardware FIFO queue and when the queue gets filled, the interface is congested. When buying a subrate circuit from a SP, something must be added to achieve the backpressure so that the TX ring is considered full. This is done by applying a parent shaper and a child policy with the actual queue configuration.

The LLQ is used for high priority traffic. When the interface is not congested, the LLQ can use all available bandwidth unless an explicit policer is configured under the LLQ.

A normal queue can use more bandwidth than it is guaranteed when there is no congestion.

When a normal queue wants to use more bandwidth than its guaranteed, it can if Continue reading

New products of the week 11.16.2015

New products of the weekOur roundup of intriguing new products. Read how to submit an entry to Network World's products of the week slideshow.Blue Jeans 3.0Key features: new integrations and centralized control, ROI and management tools. Specifically, Blue Jeans 3.0 will include: A refreshed and unified user interface offering new audio capabilities and one-click connections; WebRTC support for Google Chrome, including a new user interface, new audio capabilities, and usability improvements for frictionless meeting entry. More info.To read this article in full or to leave a comment, please click here

New products of the week 11.16.2015

New products of the weekOur roundup of intriguing new products. Read how to submit an entry to Network World's products of the week slideshow.Blue Jeans 3.0Key features: new integrations and centralized control, ROI and management tools. Specifically, Blue Jeans 3.0 will include: A refreshed and unified user interface offering new audio capabilities and one-click connections; WebRTC support for Google Chrome, including a new user interface, new audio capabilities, and usability improvements for frictionless meeting entry. More info.To read this article in full or to leave a comment, please click here

REVIEW: Best VPN routers for small business

We looked at six VPN routers designed for small businesses, ranging from the popular Cisco brand to lesser-known names like DrayTek and UTT Technologies. We setup and evaluated each to determine how they compare in regards to price, features, and user-friendliness. When choosing a VPN router, you want to pick one that supports the VPN protocol of your choice. If you’re look for an IPSec VPN, consider those that provide a way to simplify the configuration, such as the Cisco, Linksys or Netgear units. If you’re looking for a wide variety of VPN options, consider D-Link. If you’re looking for an inexpensive option, consider UTT Technologies. And if you’re looking for unique features, consider the DrayTek unit, or their other models with integrated Wi-Fi, fiber, or VoIP support.To read this article in full or to leave a comment, please click here

Hacktivists claim ISIS terrorists linked to Paris attacks had bitcoin funding

During Dateline coverage after the terrorist attacks on Paris, Lestor Holt asked, “Does this change the game in terms of intelligence?”Andrea Mitchell replied, “It does,” before discussing how intelligence missed any type of communication regarding the coordinated attacks. She added, “There’s such good surveillance on cell phones and there’s such good communications ability by the intelligence gathering in Europe, especially in France, especially in Great Britain and in the United States. So they may have been communicating via social media or through codes. And that’s the kind of thing that is very concerning to U.S. intelligence.”To read this article in full or to leave a comment, please click here

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How Facebook’s Safety Check Works

I noticed on Facebook during this horrible tragedy in Paris that there was some worry because not everyone had checked in using Safety Check. So I thought people might want to know a little more about how Safety Check works.

If a friend or family member hasn't checked-in yet it doesn't mean anything bad has happened to them. Please keep that in mind. Safety Check is a good system, but not a perfect system, so keep your hopes up.

This is a really short version, there's a longer article if you are interested.

  • How it works:

    • If you are in an area impacted by a disaster Facebook will send you a push notification asking if you are OK. 

    • Tapping the “I’m Safe” button marks that your are safe.

    • All your friends are notified that you are safe.

    • Friends can also see a list of all the people impacted by the disaster and how they are doing.

  • How do you build the pool of people impacted by a disaster in a certain area? Building a geoindex is the obvious solution, but it has weaknesses.

    • People are constantly moving so the index will be stale.

    • A geoindex of 1.5 billion Continue reading

k8s + opencontrail on AWS

For anyone interested in running a testbed with Kubernetes and OpenContrail on AWS i managed to boil down the install steps to the minimum:

  • Use AWS IAM to create a user and download a file “credentials.csv”
  • Checkout the scripts via `git clone https://github.com/pedro-r-marques/examples.git`
  • Change to the “ec2-k8s-cluster” directory (e.g. /Users/roque/src/examples/ec2-k8s-cluster)
  • Edit “credentials.sh” with the location of you csv file and user name and then “eval” this script.
  • Run ./setup.sh

The setup script will:

  • Create 5 VMs in a VPC on AWS;
  • Run the ansible provisioning script that installs the cluster;
  • Run a minimal sanity check on the cluster;
  • Launch an example;
  • Fetch the status page of the example app in order to check whether it is running successfully.

Please let me know if you run into any glitch… the “setup.sh” script can be rerun multiple times (the ansible provisioning is designed to be idempotent).

Next, I need to wrap this up with a Jenkins CI pipeline. And build permutations for:

  • kubernetes vs openshift;
  • single vs multiple network interfaces;
  • direct internet access vs http-proxy;
  • software gateway or a vSRX (for hybrid cloud interconnect);

The fun never stops !


A Handy GUI Tool for Working with APIs

In this post I’m going to share with you an OS X graphical application I found that makes it easier to work with RESTful APIs. The topic of RESTful APIs has come up here before (see this post on using cURL to interact with RESTful APIs), and RESTful APIs have been a key part of a number of other posts (like my recent post on using jq to work with JSON). Unlike these previous posts—which were kind of geeky and focused on the command line—this time around I’m going to show you an application called Paw, which provides a graphic interface for working with APIs.

Before I start talking about Paw, allow me to first explain why I’m talking about working with APIs using this application. I firmly believe that the future of “infrastructure engineers”—that is, folks who today are focused on managing servers, hypervisors, VM, storage, networks, and firewalls—lies in becoming the “full-stack engineer,” someone who has knowledge and skills across multiple areas, including automation/orchestration. In order to gain those skills in automation/orchestration, it’s pretty likely that you’re going to end up having to work with APIs. Hence, why I’m talking about this stuff, and why Continue reading

BitLocker encryption can be defeated with trivial Windows authentication bypass

Companies relying on Microsoft BitLocker to encrypt the drives of their employees' computers should install the latest Windows patches immediately. A researcher disclosed a trivial Windows authentication bypass, fixed earlier this week, that puts data on BitLocker-encrypted drives at risk.Ian Haken, a researcher with software security testing firm Synopsys, demonstrated the attack Friday at the Black Hat Europe security conference in Amsterdam. The issue affects Windows computers that are part of a domain, a common configuration on enterprise networks.When domain-based authentication is used on Windows, the user's password is checked against a computer that serves as domain controller. However, in situations when, for example, a laptop is taken outside of the network and the domain controller cannot be reached, authentication relies on a local credentials cache on the machine.To read this article in full or to leave a comment, please click here

The secret to a successful identity provider deployment: federate your identity data with a hub

This vendor-written tech primer has been edited by Network World to eliminate product promotion, but readers should note it will likely favor the submitter’s approach.

Companies are securing more users who are accessing more applications from more places through more devices than ever before, and all this diversity is stretching the current landscape of identity and access management (IAM) into places it was never designed to reach. At the same time, security has never been more paramount—or difficult to ensure, given today’s outdated and overly complex legacy identity systems. I call this the “n-squared problem,” where we’re trying to make too many hard-coded connections to too many sources, each with its own protocols and requirements.

To read this article in full or to leave a comment, please click here

How to solve today’s top three virtual environment challenges

This vendor-written tech primer has been edited by Network World to eliminate product promotion, but readers should note it will likely favor the submitter’s approach.

Virtualization is a mature technology but if you don’t have a virtualization wizard on staff managing the environment can be a challenge. Benefits such as flexibility, scalability and cost savings can quickly give way to security risks, resource waste and infrastructure performance degradation, so it is as important to understand common virtual environment problems and how to solve them.

The issues tend to fall into three main areas: virtual machine (VM) sprawl, capacity planning and change management. Here’s a deeper look at the problems and what you can do to address them:

To read this article in full or to leave a comment, please click here

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