But Does it Work?

When I was in the USAF, a long, long, time ago, there was a guy in my shop — Armand — who, no matter what we did around the shop, would ask, “but does it work?” For instance, when I was working on redoing the tool cabinet, with nice painted slots for each tool, he walked by — “Nice. But does it work?” I remember showing him where each tool fit, and how it would all be organized so we the pager went off at 2AM because the localizer was down (yet again), it would be easy to find that one tool you needed to fix the problem. He just shook his head and walked away. Again, later, I was working on the status board in the Group Readiness Center — the big white metal board that showed the current status of every piece of comm equipment on the Base — Armand walked by and said, “looks nice, but does it work?” Again, I showed him how the new arrangement was better than the old one. And again Armand just shook his head and walked away. It took me a long time to “get it” — to Continue reading

PQ Show 42 – HP Networking – Location Aware Wireless

This sponsored podcast is another in our series of recordings made at HP Discover 2014 in Barcelona, Spain. Once again, our special thanks to Chris Young for bringing us technical guests and not just fluffy marketing folks. Technical Marketing Engineer at HP Networking Yarnin Israel and Senior Research Scientist at HP Labs Souvik Sen join Packet […]

Author information

Ethan Banks

Co-host at Packet Pushers

Ethan Banks, CCIE #20655, has been managing networks for higher ed, government, financials and high tech since 1995. Ethan co-hosts the Packet Pushers Podcast, which has seen over 3M downloads and reaches over 10K listeners. With whatever time is left, Ethan writes for fun & profit, studies for certifications, and enjoys science fiction. @ecbanks
TwitterGoogle+LinkedIn

The post PQ Show 42 – HP Networking – Location Aware Wireless appeared first on Packet Pushers Podcast and was written by Ethan Banks.

PfSense VirtualBox Appliance as Personal Firewall on Linux

The tutorial explains how to set up pfSense VirtualBox appliance in order to use it as a personal firewall on Linux. It shows Linux network configuration to support this scenario and provides an installation script that automatically builds a VirtualBox virtual machine ready for pfSense installation. It also describes pfSense installation and shows minimal web configuration needed for successful connection to the Internet.

pfSense Live CD ISO disk can be downloaded from here.

1. Linux Network Configuration

We are going to install pfSsense from live CD ISO image on a VirtualBox virtual machine. To do so we must reconfigure an existing network interface, create a new one and configure new static default routes. A network topology consists of Linux Fedora with installed VirtualBox virtualizer. is shown below.

Picture1-Network_Topology

Picture 1 - Network Topology

A wireless network card is installed in Linux and presented as an interface wlp3s0. The interface wlp3s0 is the interface that connects Pfsense virtual machine to the outside world. This interface will be bridged with a first network adapter (em0) of the Pfsense virtual machine. Bridging host adapter wlp3s0 with the guest adapter em0 (WAN interface of Pfsense) will be done using vboxmanage utility and shown later in the tutorial.

As the Pfsense appliance is Continue reading

CoreOS overview

This blog is part of my ongoing series on Docker containers. In this blog, I will cover basics of CoreOS and some hands-on stuff I tried with CoreOS. As mentioned in my other blog on Docker  orchestration, CoreOS falls in the category of specialized Linux distributions that can host Containers and are suitable for massive server deployments. … Continue reading CoreOS overview →

Welcome to MovingPackets.NET!

John Herbert

Welcome to my new home! If you’ve come over here because you used to read my drivel on LameJournal, then thank you! If you’re a new visitor, you are very welcome and I hope you choose to subscribe by RSS or Email so you can get notified of new posts.

MovingPackets.net is the new name for LameJournal. All the networking and computer-related content from LameJournal has been duplicated here at MovingPackets, but the photography content is gone and I’ll attempt to stay focused on things related to moving packets around as I post here going forward.

I have a new site theme, and with the new name as well, things are still likely to change a bit here visually (I have no logo yet for example). Still, there’s no time like the present so I decided to launch the site and I’ll tweak things as we go along with the aim of making the content more easily accessible. I hope you like my new home; it’s going to take a while before it feels comfortable!

Thanks for stopping in at MovingPackets.

John.

If you liked this post, please do click through to the source at Welcome to MovingPackets.NET! and give me a share/like. Thank you!

MovingPackets.NET – The New Name for LameJournal

I’ve been quiet lately, mostly because I’ve been horribly busy but also in part because I’ve been thinking that it’s about time to rebrand LameJournal to something that better reflects the content. And to that end, MovingPackets.net has been born. All the … Continue reading →

If you liked this post, please do click through to the source at MovingPackets.NET – The New Name for LameJournal and give me a share/like. Thank you!

QoS Design Notes for CCDE

Trying to get my CCDE studies going again. I’ve finished the End to End QoS Design book (relevant parts) and here are my notes on QoS design.

Basic QoS

Different applications require different treatment, the most important parameters are:

  • Delay: The time it takes from the sending endpoint to reach the receiving endpoint
  • Jitter: The variation in end to end delay between sequential packets
  • Packet loss: The number of packets sent compared to the number of received as a percentage

Characteristics of voice traffic:

  • Smooth
  • Benign
  • Drop sensitive
  • Delay sensitive
  • UDP priority

One-way requirements for voice:

  • Latency ≤ 150 ms
  • Jitter ≤ 30 ms
  • Loss ≤ 1%
  • Bandwidth (30-128Kbps)

Characteristics for video traffic:

  • Bursty
  • Greedy
  • Drop sensitive
  • Delay sensitive
  • UDP priority

One-way requirements for video:

  • Latency ≤ 200-400 ms
  • Jitter ≤ 30-50 ms
  • Loss ≤ 0.1-1%
  • Bandwidth (384Kbps-20+ Mbps)

Characteristics for data traffic:

  • Smooth/bursty
  • Benign/greedy
  • Drop insensitive
  • Delay insensitive
  • TCP retransmits

Quality of Service (QoS) – Managed unfairness, measured numerically in latency, jitter and packetloss

Quality of Experience (QoE) – End user perception of network performance, subjective and can’t be measured

Tools

Classification and marking tools: Session, or flows, are analyzed to determine what class the packets belong to Continue reading

NFD9 Prep: NetBeez

I’m reviewing the presenters for Network Field Day 9, in particular looking at those I’m not familiar with. NetBeez is one of those making their first Tech Field Day appearance.

NetBeez

We all know that our users and the applications they access are incredibly distributed. We don’t control all the network elements, but the network team still gets the blame if things go wrong. You need greater visibility to prove it’s not the network, but getting that visibility is tough. Current options for probes aren’t always cost-effective to deploy across many sites. Many sites don’t have any local server infrastructure.

That’s where NetBeez comes in. They have developed Raspberry Pi-based agents that can easily be deployed to many locations. Plug in power, plug in a network cable, and it phones home. Go to the NetBeez dashboard, and from there you can configure the tests you want the agent to run.

Since the devices are so small, they can easily be deployed to a range of small sites, and can simulate a range of user traffic. Tests include Ping, HTTP, Traceroute, DNS. A particularly nice feature is the ability to run an ad-hoc iPerf test with custom parameters.

The dashboard shows you how the Continue reading

It’s About Application Delivery, Not Networking

Send to Kindle@DrDust tweets: @packetpushers – at the beginning you appeared very Cisco centric. Now not so much. What do you guys “like” working on? Be warned, @DrDust. This is probably not the post you’re looking for. But it’s where my mind went after reading your question. ;-) On Early Cisco-centrism I don’t especially remember that […]

Looking Ahead: My 2015 Projects

In this post, I’m going to discuss some projects that I’ve set out for myself in the upcoming year. I’ve done this in years past, and the feedback that I’ve gotten from readers is that they found these posts to be quite helpful.

I first started posting annual project lists in January 2012, when I posted a list of some projects for 2012. In January 2013, I graded myself on my progress (spoiler alert: I didn’t do very well), followed by a new 2013 project list in early February. The series of posts ends in January 2014 when I assessed my 2013 performance.

Here’s what I’m seeing for myself with regard to 2015 projects:

  1. Complete a new book. Having successfully transitioned the “Mastering VMware vSphere” series to Nick Marshall (who did an astounding job with the 5.5 release of the book), it’s time for me to get back into the book writing saddle. One of my projects for this coming year will be to complete a new book before the end of the year. This is a pretty significant effort, and it will absorb a large portion of my time and attention (as those who have written books can Continue reading

PlexxiPulse—Interested in joining our team?

If you’ve been following our blog and/or keeping up with Plexxi on social media, you may have noticed that there is a lot going on here. We recently introduced new product starter kits, began construction on our new office expansion, are working on some exciting projects, and have grown by 20 percent in the past two months. Are you interested in being a part of the Plexxi team? If so, we would love to hear from you. Check out our careers page for more information.

Below you will find our top picks for stories in the networking space this week. Have a great weekend!

In this week’s PlexxiTube video of the week, Dan Backman explains how Plexxi’s datacenter transport fabric works with optical transport gear.

Light Reading: New Plexxi Chief Makes His Mark
By Mitch Wagner
As he enters his third month in the big chair, new Plexxi CEO Rich Napolitano is retooling the company’s messaging to focus more on the benefits of software networks — using Plexxi technology, of course — and less on the abstract benefits of SDN. Napolitano took over as CEO in November after 30 years in the technology industry, most recently at EMC Continue reading

Sizing up the three popular Internet TV streaming sticks

If you’re like most folks, the back of your home entertainment center is a hive of HDMI cables, USB cords and power adaptors, not to mention the HDMI switchers necessary to cope with this cornucopia of entertainment providers. Thankfully, there is a solution: The increasingly popular streaming stick.

These Internet TV streaming devices will be the savior of every gadget-obsessed, cable-cluttered geek out there. These chewing gum-sized streaming devices can pipe the whole wide, weird and wonderful Internet into your television, with a lot less of the cable mess than you’re dealing with now.

Currently available in one of three flavors—Roku's Stick ($50), Google's Chromecast ($35), and Amazon's Fire Stick ($39)— these three devices can deliver pretty much any online content you could wish for directly to your living room. Here's a look at what these sticks have to offer:

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

1 … 3,601 3,602 3,603 3,604 3,605 … 3,793