Path MTU Discovery with DMVPN Tunnels

I played with it a bit, and was delighted to discover that the dynamic tunnel MTU mechanism operates on a per-NBMA neighbor basis, much the same as ip pim nbma-mode on the same interface type. Both features do all the right things, just like you'd hope they would.

Here's the topology I'm using:

Constrained MTU in path between R1 and R4

 interface Tunnel0  
  ip address 192.168.1.1 255.255.255.0  
  no ip redirects  
  ip mtu 1400  
  ip pim sparse-mode  
  ip nhrp map multicast dynamic  
  ip nhrp network-id 1  
  tunnel source FastEthernet0/0  
  tunnel mode gre multipoint  
  tunnel path-mtu-discovery  
  tunnel vrf TRANSIT  
 end  

 R1#show dmvpn  
 Legend:  Continue reading

BitTorrent programs can be abused to amplify distributed denial-of-service attacks

BitTorrent applications used by hundreds of millions of users around the world could be tricked into participating in distributed denial-of-service (DDoS) attacks, amplifying the malicious traffic generated by attackers by up to 50 times.DDoS reflection is a technique that uses IP (Internet Protocol) address spoofing to trick a service to send responses to a third-party computer instead of the original sender. It can be used to hide the source of malicious traffic.The technique can typically be used against services that communicate over the User Datagram Protocol (UDP), because unlike the Transmission Control Protocol (TCP), UDP does not perform handshakes and therefore source IP address validation. This means an attacker can send a UDP packet with a forged header that specifies someone else’s IP address as the source, causing the service to send the response to that address.To read this article in full or to leave a comment, please click here

Send attackers on a wild goose chase with deception technologies

Midsized companies with revenues from $100 million to $1 billion spent an average of $3 million on information security as of 2014 per “The Global State of Information Security Survey 2015” from PwC.“I promise you, bad guys are not spending $3 million to break into your organization,” says Allen Harper, chief hacker, Tangible Security. Still information burglars are getting through.And since 92 percent of IT and security professionals surveyed globally use signature-based antivirus software on their servers, despite AV’s inability to stop advanced threats and targeted attacks, according to Bit9’s 2013 Server Security Survey, exploits such as zero-days, which have no signatures give attackers the upper hand.To read this article in full or to leave a comment, please click here

DOJ calls for encryption balance that includes law enforcement needs

It’s possible for companies to design their encryption systems to allow law enforcement agencies to access customer data with court-ordered warrants while still offering solid security, U.S. Department of Justice officials said.When DOJ and FBI officials raised recent concerns over end-to-end encryption on Android and iOS mobile phones, some security experts suggested it was difficult or unsafe to build in provider access to encrypted consumer data. But many companies already offer encryption while retaining some access to user information, two senior DOJ officials said Wednesday.To read this article in full or to leave a comment, please click here

Docker Toolbox

Docker Toolbox

Espionage, Spying and Big Corporate Data, These Are a Few of China’s Favorite Things

ASERT provides a weekly threat bulletin for Arbor customers that highlights and analyzes the week’s top security events and provides other pertinent infosec material. Recently, we covered the public notification of a United Airlines breach by possible Chinese state-sponsored threat actors. In this blog, we offer an alternative hypothesis to the conclusions many have drawn regarding the motivation behind this and other recent attacks.

The Compromises

For those keeping score, the United States Office of Personnel Management (OPM), Anthem, Premera, and Carefirst Blue Cross all reported large data breaches, seemingly perpetrated by the same possible Chinese state-sponsored threat actors [1]. Research into the OPM breach provided information leading investigators to believe the same group of threat actors also compromised additional companies [2]. These investigators released IOC’s that United Airlines used to detect their own data breach in late May/early June of 2015. The data stolen reportedly included passenger manifests containing travel information and basic demographics about travelers. Additionally, according to Bloomberg, one of the individuals familiar with the case indicated information regarding United’s corporate merger and acquisition strategy was also possibly compromised.

Considering the context discussed so far, let’s highlight the current train of thought amongst many in the security Continue reading

Ensuring the web is for everyone

This is the text of an internal email I sent at CloudFlare that we thought worth sharing more widely. I annotated it a bit with links that weren't in the original.

"Tim Berners-Lee- Mosaic by Sue Edkins at Sheen Lane Centre" by Robert Smith - Own work. Licensed under CC BY-SA 4.0 via Commons

Subject: Days of future past

Folks,

One of the exciting things about working at CloudFlare is our continual push to stay on top of what's new for our customers. We've pushed things like IPv6 and SPDY in the past; and we'll soon be giving the world DNSSEC and HTTP/2. In the world of SSL we've stayed on top of changes in recommended cipher suites and offer the latest signature algorithms SHA-2 to our customers.

But as we do this we must not forget the old protocols. Because we serve a truly global audience we serve everyone on the planet. It's easy inside a Silicon Valley bubble to think that everyone is on 1Gbps Internet connection with the latest version of Chrome on a new Mac, but the worldwide reality is far different.

We see every type of machine and browser out there. And Continue reading

How Autodesk Implemented Scalable Eventing over Mesos

This is a guest post by Olivier Paugam, SW Architect for the Autodesk Cloud. I really like this post because it shows how bits of infrastructure--Mesos, Kafka, RabbitMQ, Akka, Splunk, Librato, EC2--can be combined together to solve real problems. It's truly amazing how much can get done these days by a small team.

I was tasked a few months ago to come up with a central eventing system, something that would allow our various backends to communicate with each other. We are talking about activity streaming backends, rendering, data translation, BIM, identity, log reporting, analytics, etc.  So something really generic with varying load, usage patterns and scaling profile.  And oh, also something that our engineering teams could interface with easily.  Of course every piece of the system should be able to scale on its own.

I obviously didn't have time to write too much code and picked up Kafka as our storage core as it's stable, widely used and works okay (please note I'm not bound to using it and could switch over to something else).  Now I of course could not expose it directly and had to front-end it with some API. Without thinking much I also Continue reading

IO Visor Adds Pop to the Linux Kernel

The latest open source project goes deep into the Linux kernel to improve networking.

Docker Global Hack Day #3: Update on Local Editions, Prizes and More!

Network Break 49: Oracle Scolds Customers Over Security

Take a network break! In this episode Oracle tells customers to stop security testing on its software, Arista posts a strong Q2, Symantec sells Veritas, F5 releases a new version of Big-IP and more.

The post Network Break 49: Oracle Scolds Customers Over Security appeared first on Packet Pushers.

What’s the worst nightmare for college IT?

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BitTorrent programs can be abused to amplify distributed denial-of-service attacks

BitTorrent applications used by hundreds of millions of users around the world could be tricked into participating in distributed denial-of-service (DDoS) attacks, amplifying the malicious traffic generated by attackers by up to 50 times.DDoS reflection is a technique that uses IP (Internet Protocol) address spoofing to trick a service to send responses to a third-party computer instead of the original sender. It can be used to hide the source of malicious traffic.The technique can typically be used against services that communicate over the User Datagram Protocol (UDP), because unlike the Transmission Control Protocol (TCP), UDP does not perform handshakes and therefore source IP address validation. This means an attacker can send a UDP packet with a forged header that specifies someone else’s IP address as the source, causing the service to send the response to that address.To read this article in full or to leave a comment, please click here

Liskov Substitution and Modularity in Network Design

Furthering the thoughts I’ve put into the forthcoming book on network complexity…

One of the hardest things for designers to wrap their heads around is the concept of unintended consequences. One of the definitional points of complexity in any design is the problem of “push button on right side, weird thing happens over on the left side, and there’s no apparent connection between the two.” This is often just a result of the complexity problem in its base form — the unsolvable triangle (fast/cheap/quality — choose two). The problem is that we often don’t see the third leg of the triangle.

The Liskov substitution principle is one of the mechanisms coders use to manage complexity in object oriented design. The general idea is this: suppose I build an object that describes rectangles. This object can hold the width and the height of the rectangle, and it can return the area of the rectangle. Now, assume I build another object called “square” that overloads the rectangle object, but it forces the width and height to be the same (a square is type of rectangle that has all equal sides, after all). This all seems perfectly normal, right?

Now let’s say Continue reading

10 security technologies destined for the dustbin

Perhaps nothing, not even the weather, changes as fast as computer technology. With that brisk pace of progress comes a grave responsibility: securing it.Every wave of new tech, no matter how small or esoteric, brings with it new threats. The security community slaves to keep up and, all things considered, does a pretty good job against hackers, who shift technologies and methodologies rapidly, leaving last year’s well-recognized attacks to the dustbin.[ Deep Dive: How to rethink security for the new world of IT. | Discover how to secure your systems with InfoWorld's Security newsletter. ] Have you had to enable the write-protect notch on your floppy disk lately to prevent boot viruses or malicious overwriting? Have you had to turn off your modem to prevent hackers from dialing it at night? Have you had to unload your ansi.sys driver to prevent malicious text files from remapping your keyboard to make your next keystroke reformat your hard drive? Did you review your autoexec.bat and config.sys files to make sure no malicious entries were inserted to autostart malware?To read this article in full or to leave a comment, please click here

Worth Reading: Labellio

Labellio is the world’s easiest deep learning web service for computer vision. It aims to provide a deep learning environment for image data where non-experts in deep learning can experiment with their ideas for image classification applications. via NVidia

The post Worth Reading: Labellio appeared first on 'net work.

iPexpert’s Newest “CCIE Wall of Fame” Additions 8/17/2015

Please join us in congratulating the following iPexpert students who have passed their CCIE lab!

This Week’s CCIE Success Stories

• Alemneh Nigussi, CCIE #28272 (Data Center)
  (He’s a 3x CCIE! He also has Voice and Routing/Switching.)
• K.G. Pramod, CCIE #49662 (Data Center)
• Mohamed Ahmed Ali, CCIE #34760 (Security)
• Muhammad Adil, CCIE #49605 (Data Center)

We Want to Hear From You!

Have you passed your CCIE lab exam and used any of iPexpert’s self-study products, or attended a CCIE Bootcamp? If so, we’d like to add you to our CCIE Wall of Fame!

4G Edge Routers On The Rise

Web-Scale IT: The Enterprise Impact