Wget off the leash

As we all know, to grab a website with wget, we'll use the "-r" option to "recurse" through all the links. There is also the '-H' option, means that wget won't restrict itself to just one host. In other words, with '-r -H' together, it'll try to spider the entire Internet. So I did that to see what would happen.

Well, for a 32-bit bit process, what happened is that after more than a month, it ran out of memory. It maintained an ever growing list of URLs that it has to visit, which can easily run in the millions. At a hundred bytes per URL and 2-gigabytes of virtual memory, it'll run out of memory after 20 million URLs -- far short of the billions on the net. That's what you see below, where 'wget' has crashed exhausting memory. Below that I show the command I used to launch the process, starting at cnn.com as the seed with a max timeout of 5 seconds.



How much data did I download from the Internet? According to 'du', the answer is 18-gigabytes, as seen in the following screenshot:



It reached 79425 individual domains, far short of the millions it held Continue reading

Six-month anniversary scan for Heartbleed

I just launched my six-month anniversary scan for Heartbleed. I'll start reporting early results tomorrow afternoon. I'm dialing the scan to run slowly and spreading it across four IP addresses (and 32k ports) in order to avoid unduly alarming people.

If you would like the results of the scan for your subnet, send us your address ranges to our "abuse@" email address. We'll lookup the abuse contact email for those ranges and send you what we found for that range. (This offer good through the end of October 2014).



Here is a discussion of the options.

--conf /etc/masscan/masscan.conf
You don't see this option, but it's the default. This is where we have the 'excluderanges' configured. Because we exclude everyone who contacts us an "opts-out" of our white-hat scans, we are down to scanning only 3.5 billion hosts now, out of around 4 billion.

0.0.0.0/0
The the "/0" means "the entire Internet". Actually, any valid IPv4 address can replace the 0.0.0.0 and it'll produce the same results, such as "127.0.0.0/0" to amuse your friends.

-p443
This says to scan on port 443, the default SSL port. At some point in Continue reading

Cisco NX-API 1.0 Update

If you weren’t paying attention, it was easy to miss. NX-API, Cisco’s new JSON/XML switch API is now shipping as version 1.0. NX-API originated on the Nexus 9000 platform created by the Insieme group, and I’ve explored this in detail before. In review, NX-API is a new, programmatic method of interacting with a Cisco Nexus switch. In many ways, Cisco is playing catch-up here, since this interface is really just a wrapper for the CLI (admittedly with some convenient output parsing), and most of their competitors have had similar interfaces for a while.

Cisco NX-API 1.0 Update

If you weren’t paying attention, it was easy to miss. NX-API, Cisco’s new JSON/XML switch API is now shipping as version 1.0. NX-API originated on the Nexus 9000 platform created by the Insieme group, and I’ve explored this in detail before. In review, NX-API is a new, programmatic method of interacting with a Cisco Nexus switch. In many ways, Cisco is playing catch-up here, since this interface is really just a wrapper for the CLI (admittedly with some convenient output parsing), and most of their competitors have had similar interfaces for a while.

White Box Switching: Broadcom StrataXGS Tomahawk

A previous post listed the excitement I felt when reading through the Cavium XPliant announcement. Programmable fast packet forwarding hardware? Awesome! In a previous life I worked with embedded electronics and wrote several interesting algorithms in C and assembly for applications from noise filtering for AD conversion, LCD screen drivers and TCP/IP stacks (which was fun). This kind of thing really excites me. Nuff said.

So I was more than happy to read the announcement from Broadcom announcing their latest child, the StrataXGS® Tomahawk™. This chipset is formed from more than 7 billion transistors, can forward packets at 3.2Tbps and is optimised for SDN and high port density devices, not to mention it is an authoritative chipset for 25GE and 50GE Ethernet and provides sub 400ns port-to-port operation. Sound good? It’s the next evolutionary step from Trident II and matches the offering from Cavium with their XPliant child.

The Broadcom StrataXGS® Tomahawk™ can deliver 32x 100GE, 64x 40/50GE or 128 ports of of 25GE on a single chip. SINGLE CHIP! This all boils down to 25Gbps per-lane interconnections. Bit of a waste perhaps for 40GE? Which is good considering this chipset is based on upgrading switches with 10GE host Continue reading

Traceroute – A Small Tool for Big Problems

Basics is must for Network Engineer.Traceroute is an imp and handy tool while  troubleshooting any network issue.How Traceroute works ? Whats the concept behind it ? Its task is to determine  the path taken by packet to reach its destination .Before going further ,lets see the IP header . 0                   1                   2                   3 0 1 […]

Author information

Anurudh Dubey

Anurudh Dubey CCIE##44298 is Network Engineer.A thorough professional with over all 8 years’ rich experience in the IT/Telecom and Networking sector.Always try to learn new as their is no limit for learning.In addition, Anurudh is a : Blogger at http://crazyrouters.wordpress.com/
LinkedIn

The post Traceroute – A Small Tool for Big Problems appeared first on Packet Pushers Podcast and was written by Anurudh Dubey.

Rant: Oh, You Want It To Work As Well ?


Advertise here with BSA

When we spend millions of dollars on a network product we don't actually expect it to work. That's why it is completely normal to see job advertisement for a 5 day contract engagement to perform a validation that product doesn't have any bugs. Think about the cost incurred by this company to check if this Cisco Nexus is actually fit for purpose.


Advertise here with BSA

The post Rant: Oh, You Want It To Work As Well ? appeared first on EtherealMind.

Status Quo of Open Source SDN and IETF Standardization

Status Quo of Open Source SDN and IETF Standardization

by Hariharan Ananthakrishnan, Distinguished Engineer - October 7, 2014

Open source SDN projects like OpenDaylight are offering an open platform for network programmability to network elements such as routers and switches. They rely on standards-based approaches to provide true multi-vendor support. The IETF (and its various working groups) is moving slowly towards creating the standards needed for widespread SDN development and adoption.

OpenDaylight uses topology models, described in YANG, that are getting standardized in the NETMOD and I2RS IETF working groups. It also uses emerging protocol extensions for PCEP and BGP-LS that are being discussed in the PCE and BGP IETF working groups. OpenDaylight, with more than 200 developers, just last week issued Helium, its second software release.

On the other hand, the IETF is progressing more slowly on standardization. PCEP extensions to support statefullness and PCE-initiated LSP are still in draft form. Major routing vendors are finding it difficult to match up the draft updates to their release cycles. As a result of this, customers are challenged to pair up the draft version supported by their routing software with the controller version.

This slowness can cause other issues. Continue reading

Cisco ISR 4000 – Now with more licensing!

This week an Interop NYC, Cisco launched it’s ISR 4000 Series. This is a new approach for them focused on delivering services to your branch offices. Cisco has dubbed this new approach the Intelligent WAN (IWAN) — but before we talk about that, let’s talk about hardware. Those of us that have been paying attention remember that Cisco announced the ISR 4451 at Cisco Live 2013. The 4451 boasts a multi-core CPU architecture that runs the all to familiar by now IOS-XE. It’s 1-2 Gbps of throughput made it a perfect fit for those looking for something in between a 3945 and an ASR1k. Now Cisco that Cisco has brought the rest of the family into the spotlight it all makes sense.


ISR 4k Family

IWAN focuses on a few key fundamentals to get more bang for your buck. And because Cisco has stuffed some serious hardware into the 4k you won’t see the same performance hits you’re all too familiar with in the ISR series. But more on that in a second. Here is Cisco’s break on on the Intelligent WAN…

  • Transport Independence – Providing flexibility when it comes to connectivity. DMVPN can help augment your network with low cost bandwidth for Continue reading

On choice-supportive bias and the need for paranoid optimism

In cognitive science, choice-supportive bias is the tendency to view decisions you have made in the most favorable light. Essentially, we are all hardwired to subconsciously reinforce decisions we have made. We tend to retroactively ascribe positive characteristics to our selections, allowing us to actually strengthen our conviction after the point of decision. This is why we become more resolute in our positions after the initial choice is made.

In corporate culture, this is a powerful driver behind corporate conviction. But in rapidly-shifting landscapes, it can be a dangerous mindset. Consistently finding reasons to reinforce a decision can insulate companies from other feedback that might otherwise initiate a different response. A more productive mindset, especially for companies experiencing rapid evolution, is paranoid optimism.

The need for choice-supportive bias

Choice-supportive bias can actually be a powerful unifier in companies for whom the right path is not immediately obvious. Throughout most of the high-tech space, strategic direction is murky at best. Direction tends to be argued internally before some rough consensus is reached. But even then, the constantly changing technology that surrounds solutions in high-tech means that it can be difficult to stage a lasting rally around a particular direction.

Failing some Continue reading

API-jinks

Dastardly-vi

Network programmability is a very hot topic.  Developers are looking to the future when REST APIs and Python replaces the traditional command line interface (CLI).  The ability to write programs to interface with the network and build on functionality is spurring people to integrate networking with DevOps.  But what happens if the foundation of the programmable network, the API, isn’t the rock we all hope it will be?

Shiny API People

APIs enable the world we live in today.  Whether you’re writing for POSIX or JSON or even the Microsoft Windows API, you’re interacting with software to accomplish a goal.  The ability to use these standard interfaces makes software predictable and repeatable.  Think of an API as interchangeable parts for software.  By giving developers a way to extract information or interact the same way every time, we can write applications that just work.

APIs are hard work though.  Writing and documenting those functions takes time and effort.  The API guidelines from Microsoft and Apple can be hundreds or even thousands of pages long depending on which parts you are looking at.  They can cover exciting features like media services or mundane options like buttons and toolbars.  But each of these Continue reading

INE R&Sv5 Workbook Full-Scale Practice Lab1 made in GNS3

How does the internet work - We know what is networking

Yesterday INE finally added a Full-Scale LAB in their new CCIE Route and Switching blueprint 5 workbook. I realized this morning that you maybe don’t want to spend half of your day (like me) configuring this topology in GNS3. Better to just take it from here and start your lab right away. In my study […]

INE R&Sv5 Workbook Full-Scale Practice Lab1 made in GNS3

DNSSEC: An Introduction

At CloudFlare our mission is to help build a better Internet. Part of this effort includes making web sites faster, more reliable, and more trustworthy. The obvious first choice in protocols to help make websites more secure is HTTPS. CloudFlare’s latest product—Universal SSL—helps web site operators provide a trustworthy browsing experience for their site visitors by giving their site HTTPS support for free. In this blog post we look at another protocol, DNS, and explore one proposal to improve its trustworthiness: DNSSEC.

DNS is one of the pillars of authority on the Internet. DNS is used to translate domain names (like www.cloudflare.com) to numeric Internet addresses (like 198.41.214.163)—it’s often referred to as the “phone book of the Internet”.

DNSSEC is a set of security extensions to DNS that provides the means for authenticating DNS records. CloudFlare is planning to introduce DNSSEC in the next six months, and has brought Olafur Gudmundsson, one of the co-inventors of DNSSEC, on board to help lead the project.

CC BY 2.0 by Eric Fischer

Introduction

The Domain Name System (DNS) is one of the oldest and most fundamental components of the modern Internet. As the Continue reading

Go Up or Go Wide

You say, the world doesn't need CCIE anymore with the raise of SDN. I say, we still need CCIE, but those who can adapt. You say, my words are just futile last ditch effort to show the importance of CCIE certification. I say, even I still work for Cisco but I don't work for CCIE program, and I get paid not because of my certifications.

If we have data, let's look at data. If all we have are opinions, let's go with mine. 
(Jim Barksdale, former CEO of Netscape )

So let's look at the data to make the discussion more fruitful. If you look at Cisco revenue of each product line for the past 5 years, we see there is decline for NGN Routing and Switching business. And yes, Data Center business is growing in fast rate. And Data Center business includes unified computing, next generation fabric, cloud and most Cisco SDN solutions that are available today.


However, if you do a simple math you can see the combined revenue of Routing & Switching business is still close to half Cisco revenue as of today. We are talking about more than 20 billion USD business. It's declining Continue reading

Who named “shellshock”?

Because it's terribly important to cybersec, many are debating the origin of the name "shellshock". I thought I'd write up the definitive answer.

The answer is that it came from this tweet by Andreas Lindh. That's the absolute origin of the term. Andreas made it up himself.



Also, to some extent Davi Ottenheimer deserves some credit for starting the conversation among a bunch of people with his tweet saying "it's not big until there's a logo". Lots of people posted logos as that point.

Also to some extent I deserve some credit for then pimping the "shellshock" name in my blogposts, which received a lot of attention in the early hours of the shellshock crisis. As you can see from the pageview stats below, these posts got a lot of attention. Also, most of the early news stories on "real" news websites referenced me and my posts. Those news sites got the name from me, and I got it from Andreas and nobody else.



I suspect what really helped it along is that when I scanned the Internet for the bug, putting it in everybody's webserver logs. I included a pointer to the "shellshock scan" post in the Continue reading

HP talks SDN at Interop NYC 2014

I generally try to avoid combing my thoughts about presentations, but I have to mention that after sitting down with Glue Networks and their “SDN” presentation, it was truly a breath of fresh air to hear from HP. They went into some details on how they demonstrated the capabilities of their SDN platform. They purposely stretched their network out the limits of what they thought was possible.

On top of that, they spent some time talking about the launch of the very first SDN application ecosystem to market. I have to say, this is a fantastic idea and I’m glad that they brought it to fruition. Not only will the App Store help customers understand the real value behind SDN, as well as discover specific network applications that could help solve problems they’re facing today.

Take a few minutes to listen to Chris Young and Jeff Enters from HP give a fantastic white boarding session on the architecture behind the network they brought to Interop and the specific challenges of building it. Checkout http://hp.com/go/sdn for more info.

Standard TFD Disclaimer

While Cisco and HP were responsible for paying a portion of the travel and lodging costs for me during Continue reading

1 … 3,650 3,651 3,652 3,653 3,654 … 3,795