Network Troubleshooting with ThousandEyes
My first experience with ThousandEyes was a year ago at Network Field Day 6, where they were kind enough to give us a tour of their office, and introduce us to their products. I’ve been fairly distracted since then, but kept an eye on what other delegates like Bob McCouch were doing with the product since that demo. A year later, at Network Field Day 8, they presented again. If you’ve never heard of ThousandEyes, and/or would like an overview, watch Mohit’s (CEO) NFD8 introduction:Closing Comments on Old Posts
One of the great things about this site is the interaction I enjoy with readers. It’s always great to get comments from readers about how an article was informative, answered a question, or helped solve a problem. Knowing that what I’ve written here is helpful to others is a very large part of why I’ve been writing here for over 9 years.
Until today, I’ve left comments (and sometimes trackbacks) open on very old blog posts. Just the other day I received a comment on a 4 year old article where a reader was sharing another way to solve the same problem. Unfortunately, that has to change. Comment spam on the site has grown considerably over the last few months, despite the use of a number of plugins to help address the issue. It’s no longer just an annoyance; it’s now a problem.
As a result, starting today, all blog posts more than 3 years old will automatically have their comments and trackbacks closed. I hate to do it—really I do—but I don’t see any other solution to the increasing blog spam.
I hope that this does not adversely impact my readers’ ability to interact with me, but it is Continue reading
The Chassis Switch is Dead
The Chassis Switch is Dead. For most networks, chassis-based switches are no longer appropriate due to cost, inflexibility and risk. I see this as similar to servers, in that server blade chassis are no longer appropriate for most organisations. The alternatives are already better for cost & flexibility. The real question is what our management model will look like for those alternatives.
Dead Collector: ‘Ere, he says he’s not dead.
Leaf-Spine: Yes he is.
Chassis: I’m not.
Dead Collector: He isn’t.
Leaf-Spine: Well, he will be soon, he’s very ill.
Chassis: I’m getting better.
Leaf-Spine: No you’re not, you’ll be stone dead in a moment.
(With apologies to Monty Python)
Blade Servers…
In the late 1990s, and early 2000s, server buying patterns changed significantly. Previously we had a few “Big Iron” Unix systems, but cheaper Intel-based systems changed the economics dramatically. This lead to a rapid sprawl in the number of physical servers.
In the second half of the 2000s, server blades appeared as a seductive answer. They promised simpler management of pools of systems, greater density, better efficiencies, and operational cost savings. Vendors promised long term “investment protection”, assuring us that we could keep the chassis, and upgrade blades Continue reading
Internet of Things roundtable: Experts discuss what to look for in IoT platforms
Networking is at the heart of every Internet of Things deployment, connecting sensors and other “Things” to the apps that interpret the data or take action.
But these are still early days. Assembling an IoT network from commercial off-the-shelf components is still, let’s just say, a work in progress. This will change over time, but for now the technical immaturity is being addressed by System Integrators building custom code to connect disparate parts and by a new class of network meta-product known as the IoT Platform.
IoT Platform products are still in their infancy, but there are already more than 20 on the market today. Approaches vary, so when making a build or buy decision, consider these critical areas of IoT Platform tech: security, sensor compatibility, analytics compatibility, APIs and standards.
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What is the difference between tunnel | transport mode in IPsec
How does the internet work - We know what is networking
Intro IPsec making VPN connection possible. I enables to basically simulate a leased line across public Internet and thus enable us to get secure connection across unsecured environment. It enables encryption, authentication and protection of our data when sent across insecurity of the world’s biggest internetwork – Internet. It’s the cheap way to simulate a leased […]
What is the difference between tunnel | transport mode in IPsec
Lessons Drawn from the Rise of Server Virtualization
It has become common to draw analogies to the rise of server virtualization during the early-mid 2000’s to attempt to understand how network virtualization will change the way we build data center networks, both virtual and physical.
This is a useful tool, as there are clear similarities.
Server virtualization changed the amount of time it took to get a new compute resource up and running from weeks (order hardware, rack gear, install OS) to hours or even minutes. It allowed location independence, so admins could start VMs wherever capacity was available, and move them around at will.
Network virtualization is starting to provide similar benefits to the network. Creating a new virtual network can be done in minutes, compared to hours if we have to file a ticket with the networking team to provision a new VLAN and plumb it across a the physical network. And the scope of VM mobility can be increased radically, as VMs are no longer bound by size-limited physical L2 domains.
But there is one place the analogy breaks down, at least with networking from OEMs with the traditional proprietary appliance approach.
First, let’s back up briefly and examine something I glossed over when talking Continue reading
Closing Comments on Old Posts
One of the great things about this site is the interaction I enjoy with readers. It’s always great to get comments from readers about how an article was informative, answered a question, or helped solve a problem. Knowing that what I’ve written here is helpful to others is a very large part of why I’ve been writing here for over 9 years.
Until today, I’ve left comments (and sometimes trackbacks) open on very old blog posts. Just the other day I received a comment on a 4 year old article where a reader was sharing another way to solve the same problem. Unfortunately, that has to change. Comment spam on the site has grown considerably over the last few months, despite the use of a number of plugins to help address the issue. It’s no longer just an annoyance; it’s now a problem.
As a result, starting today, all blog posts more than 3 years old will automatically have their comments and trackbacks closed. I hate to do it—really I do—but I don’t see any other solution to the increasing blog spam.
I hope that this does not adversely impact my readers’ ability to interact with me, but it is Continue reading
SDN Use Case: Content Filtering
K-12 schools face unique challenges with their IT infrastructure. Their user base needs access to a large amount of information while at the same time facing restrictions. While it does sound like some corporate network policies, the restrictions in the education environment are legal in nature. Schools must find new ways to provide the assurance of restricting content without destroying their network in the process. Which lead me to ask: Can SDN Help?
Online Protection
The government E-Rate program gives schools money each year under Priority 1 funding for Internet access. Indeed, the whole point of the E-Rate program is to get schools connected to the Internet. But we all know the Internet comes with a bevy of distractions. Many of those distractions are graphic in nature and must be eliminated in a school. Because it’s the law.
The Children’s Internet Protection Act (CIPA) mandates that schools and libraries receiving E-Rate funding for high speed broadband Internet connections must filter those connections to remove questionable content. Otherwise they risk losing funding for all E-Rate services. That makes content filters very popular devices in schools, even if they aren’t funded by E-Rate (which they aren’t).
Content filters Continue reading
New fiber connector is nifty
Corning has recently teamed up with Intel in introducing some new optical equipment. Corning's contribution (fibers, connectors) likely mean there will be some unfamiliar looking optical infrastructure in your data center soon.The fiber is a new 1310nm singlemode variety that Corning touts as "bend-insensitive". The minimum allowable bend radius of this fiber is 7.5mm. This is impressive, but expected under ITU-T G.657.B.
More interesting is the MXC connector. This is a push-on connector with a locking tab like the 8P8C connectors used for twisted pair Ethernet. It supports up to 64 fiber strands, each running at 25Gb/s.
 |
| MXC connector. Image from Corning-Intel Whitepaper. |
The only place I've seen this fiber or connector in use is on a prototype 100G CLR4 transceiver shot by Greg Ferro at the Intel Developer Forum a couple of weeks ago.
 |
| Greg's shot of CLR4 transceivers with MXC connectors. |
It seems the MXC connector will be used not Continue reading
Do You Really Need Investment Protection for Your Network ?
When the sales grunt talks about investment protection, its sure sign that they have run out of features, functions or value propositions to sell you. But do you really need investment protection or is it just another revenue stream for vendors (and a cost for you).
The post Do You Really Need Investment Protection for Your Network ? appeared first on EtherealMind.
Protecting Junos config
In the middle of a migration, and I just discovered the ability to protect parts of the Junos configuration from modification by other users. Could be quite useful!
[edit]
root@VMX1# show system services
[edit]
root@VMX1# protect interfaces
[edit]
root@VMX1# show interfaces
##
## protect: interfaces
##
ge-0/0/0 {
description "LINK TO VMX0";
vlan-tagging;
mtu 2000;
encapsulation flexible-ethernet-services;
unit 10 {
vlan-id 10;
family inet {
address 10.1.1.2/30;
}
}
}
[edit]
root@VMX1# set interfaces ge-0/0/1 description "LINK TO NOWHERE"
warning: [interfaces] is protected, 'interfaces ge-0/0/1' cannot be created
[edit]
root@VMX1#
It’s the Applications, Stupid (Part 2 of 3)!
In part 1 of this series, I mentioned a customer that was starting to understand how to build application policy into their deployment processes and in turn was building new infrastructure that could understand those policies. That’s a lot of usage of the word “policy” so it’s probably a good idea to go into a bit more detail on what that means.
In this context, policy refers to how specific IT resources are used in accordance with a business’s rules or practices. A much more detailed discussion of policy in the data center is covered in this most excellent networkheresy blog post (with great additional discussions here and here). But suffice it to say that getting to full self-service IT nirvana requires that we codify business-centric policy and encapsulate the applications with that policy.
The goals of the previously mentioned customer were pretty simple, actually. They wanted to provide self-service compute, storage, networking, and a choice of application software stacks to their vast army of developers. They wanted this self-service capability to extend beyond development and test workloads to full production workloads, including fully automated deployment. They wanted to provide costs back to the business that were on par Continue reading
Connecting Virtual Routers to the Outside World
Stefan de Kooter (@sdktr) sent me a follow-up question to my Going All Virtual with Virtual WAN Edge Routers blog post:
How would one interface with external Internet in this scenario? I totally get the virtual network assets mantra, but even a virtual BGP router would need to get a physical interconnect one way or another.
As always, there are plenty of solutions depending on your security needs.
Read more ...GET VPN, it is all about group.
GET VPN uses a group security paradigm comparing to the traditional point-to-point security paradigm like DMVPN, GRE IPSec or SSL. Do not confuse with any-to-any mesh which is the result of n(n-1)/2 point-to-point security associations between n peers. We are talking about group security association (SA), group states and group keys. Because each group member […]
White Box Switching: Goodbye Trident II, Hello Cavium XPliant
Original Design Manufacturers (ODMs) that produce incumbent profit busting white box switching technology could soon be releasing the next wave of programmable networking based on technology from a silicon company best known for it’s encryption products. Cavium have released the XPliant chipset which it acquired from a $90m purchase earlier this year. This chipset comes in four flavours varying from 880 Gbps to 3.2 Tbps. This results in devices having 128×25 Gbps switching lanes allowing switches with 32x100GbE, 64x 50/40GbE, or 128x 25/10GbE ports in a single device. The highest speed Cavium device is currently twice the speed of the next highest merchant silicon offering, however merchant vendors will catch up with the speed aspect before too long. The important part here to remember is this chipset is programmable and is touted to be released with support for Generic Network Virtualisation Encapsulation (GENEVE) out of the box, along with a “simulator” for product designers to test their code against. All designed to increase the speed to market and decrease delay.
Let’s take an ODM switch from the likes of Accton that is currently based on the venerable Trident II chipset. Current merchant silicon chipsets limit the features to those Continue reading
IPv6 Networking Detection Case #141 – Part 2: The Solution
Part 2: The Solution Ready for part 2? Have you read part 1 w/ the facts and clues? If not, go read that now before you continue. Part 1: The Facts and Clues Review the Facts and Clues Again Last we played we were ON R1 and unable to ping the IPv6 address […]
Author information
The post IPv6 Networking Detection Case #141 – Part 2: The Solution appeared first on Packet Pushers Podcast and was written by Denise "Fish" Fishburne.
SDN control of hybrid packet / optical leaf and spine network
The short video above shows how the Calient optical circuit switch (OCS) uses two grids of micro-mirrors to create optical paths. The optical switching technology has a number of interesting properties:
- Pure optical cut-through, the speed of the link is limited only by the top of rack transceiver speeds (i.e. scales to 100G, 400G and beyond without having to upgrade the OCS)
- Ultra low latency - less than 50ns
- Lower cost than an equivalent packet switch
- Ultra low power (50W vs. 6KW for comparable packet switch)
The diagram shows the hybrid network that was demonstrated. The top of rack switches are bare metal switches running Cumulus Linux. The spine layer consists of a Cumulus Linux bare metal switch and a Calient Technologies optical circuit switch. The bare metal Continue reading
Internets of Interest – 22 September 2014
Collection of useful, relevant or just fun places on the Internets for 22 September 2014 and a bit commentary about what I've found interesting about them:
The post Internets of Interest – 22 September 2014 appeared first on EtherealMind.
