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Category Archives for "Security"

Absorbing DDoS with Communities

Distributed Denial of Service attacks can damage your business—and they can be difficult to manage or counter. While there are a number of tools available to counter DDoS attacks, particularly in the commercial space, and there are a number of widely available DDoS protection services, sometimes it’s useful to know how to counter a DDoS on your own. One option is to absorb attacks across a broader set of inbound nodes. Let’s use the network below to illustrate (though often the scale needs to be quite a bit larger for this solution to be useful in the real world).

ddos-spreading

Assume, for the moment, that the attacker is injecting a DDoS stream from the black hat, sitting just behind AS65004. There are customers located in AS65001, 2, 3, 4, and 5. For whatever reason, the majority of the attacker’s traffic is coming in to site C, through AS65003. Normally this is a result of an anycast based service (such as active-active data centers, or a web based service, or a DNS service), combined with roughly geographical traffic patterns. Even a DDoS attack from a mid sized or large’ish botnet, or reflection off a set of DNS servers, can end up being Continue reading

Poland’s Poznań Science and Technology Park Upgrades Its Infrastructure-as-a-Service Model with VMware NSX

Poznań Science and Technology Park—known in Polish as Poznańskiego Parku Naukowo-Technologicznego, or PPNT—supports the incubation of start-ups and technology companies in Poland through co-operation with science, business, and technology enterprises. Its facilities and services include laboratories, office space, and specialized research equipment, as well as IT infrastructure services like server colocation and hosting, system monitoring servers, storage space, and data transmission infrastructure leasing.

To build a virtual, multi-tenant, private infrastructure-as-a-service cloud, on a flexible billing schedule, for its demanding customers, PPNT opted for an integrated solution that included VMware vSphere, VMware vCloud Director, and VMware NSX. The business benefits became clear immediately. PPNT’s new, high-performance environment enabled robust management capabilities, and guaranteed security and fault-tolerant access. Plus, resource provisioning time was reduced from days to seconds.

Says manager of the PPNT DataCenter Tomasz Łukaszewicz: “VMware NSX, the network virtualization platform for the Software-Defined Data Center, enables our customers to create, save, delete, and restore virtual networks on demand, without reconfiguring the physical network. It also provides a better security model.”

Read the complete case study

The post Poland’s Poznań Science and Technology Park Upgrades Its Infrastructure-as-a-Service Model with VMware NSX appeared first on The Network Virtualization Blog.

Technology Short Take #68

Welcome to Technology Short Take #68, my erratically-published collection of links, articles, and posts from around the web—all focused on today’s major data center technologies. I’ve been trying to stick to a schedule that has these posts published on a Friday, but given the pending holiday weekend I wanted to get this out a bit early. As always, I hope that something I’ve included here proves useful to you.

Networking

Split Tunnel Insecurities

I really dislike corporate VPNs that don’t allow split tunneling—disconnecting from the VPN to print on a local printer, or access a local network attached drive, puts a real crimp in productivity. In the case of services reachable over both IPv6 and IPv4, particularly if the IPv6 path is preferred, split tunneling can be quite dangerous, as explained in RFC7359. Let’s use the network below to illustrate.

rfc7359-illustrated

In this network, host A is communicating with server B through a VPN, terminated by the VPN concentrator marked as “VPN.” Assume the host is reachable on both 192.0.2.1 and 2001:fb8:0:1::1. The host, the upstream router, the network in the cloud, and the server are all IPv6 reachable. When the host first connects, it will attempt both the IPv6 and IPv4 connections, and choose to use the IPv6 connection (this is what most current operating systems will do).

The problem is: the VPN connection doesn’t support IPv6 at all—it only supports IPv4. Because IPv6 is preferred, the traffic between the host and the server will take the local IPv6 connection, which is not encrypted—the blue dash/dot line—rather than the encrypted IPv4 tunnel—the red dashed line. The user, host, and Continue reading

Accessing ASA CLI in Firepower Threat Defence

I’ve recently loaded Firepower Threat Defense on an ASA5525 for my home Internet firewall. For those unfamiliar with FTD, it is basically a combination of critical ASA features and all of the Cisco Firepower features in a single image and execution space. So unlike Firepower Services, which runs separately inside the same ASA sheet metal,  FTD takes over the hardware. Once the image installed onto the hardware, the firewall is attached to and managed by a Firepower Management Console.

For those that still want to (or need to) get under the covers to understand the underpinnings or do some troubleshooting of the ASA features, it is still possible to access the familiar CLI. The process first requires an ssh connection to the management IP of the FTD instance, then access expert mode and enter the lina_cli command.

MacBook:~ paulste$ ssh [email protected]
Password:
Last login: Thu Jun 23 18:16:43 2016 from 192.168.1.48

Copyright 2004-2016, Cisco and/or its affiliates. All rights reserved.
Cisco is a registered trademark of Cisco Systems, Inc.
All other trademarks are property of their respective owners.

Cisco Fire Linux OS v6.0.1 (build 37)
Cisco ASA5525-X Threat Defense v6.0.1  Continue reading

Use the freakin’ debugger

This post is by a guy who does "not use a debugger". That's stupid. Using a friendly source-level debugger (Visual Studio, XCode, Eclipse) to step line-by-line through working code is what separates the 10x programmers from the wannabes. Yes, it's a bit of a learning hurdle, and creating "project" files for small projects is a bit of a burden, but do it. It'll vastly improve your coding skill.

That post quotes people like Rob Pike saying that stepping line-by-line is a crutch, that instead you should be able to reason about code. And that's true, if you understand what you are doing completely.

But in the real world, you never do. Programmers are constantly forced to stretch and use unfamiliar languages. Worse yet, they are forced to use unfamiliar libraries. Documentation sucks, there's no possible way to understand APIs than to step through code -- either watching the returned values, or compiling their source and stepping into it.

As an experienced programmer, it's true I often don't step through every line. The lines I understand completely, the ones I can fully reason about, I don't bother. But the programmer spends only a small percentage of their time on things Continue reading

On differential privacy

Over the past several weeks, there’s been a lot of talk about something called “differential privacy.” What does this mean, how does it work, and… Is it really going to be effective? The basic concept is this: the reason people can identify you, personally, from data collected off your phone, searches, web browser configuration, computer configuration, etc., is you do things just different enough from other people to create a pattern through cyber space (or rather data exhaust). Someone looking hard enough can figure out who “you” are by figuring out patterns you don’t even think about—you always install the same sorts of software/plugins, you always take the same path to work, you always make the same typing mistake, etc.

The idea behind differential security, considered here by Bruce Schneier, here, and here, is that you can inject noise into the data collection process that doesn’t impact the quality of the data for the intended use, while it does prevent any particular individual from being identified. If this nut can be cracked, it would be a major boon for online privacy—and this is a nut that deserves some serious cracking.

But I doubt it can actually be cracked Continue reading

Reverse Turing testing tech support

So I have to get a new Windows license for a new PC. Should I get Windows 10 Home or Windows 10 Professional? What's the difference?

So I google the question, which gives me this website:

Ooh, a button that says "Download Table". That's exactly what I want -- a technical list without all the fluff. I scroll down to the parts that concern me, like encryption.


Wait, what? What's the difference between "Device Encryption" and "BitLocker"? I though BitLocker was Device Encryption?? Well, the purchase screen for Windows 10 has this friendly little pop out offering to help. Of course, as a techy, I know that such things are worse than useless, but I haven't tried one in a while, so I thought if I'd see if anything changed.

So up pops a chat window and we start chatting:

So at first he says they are the same. When I press him on the difference, he then admits they are different. He can't read the document I'm reading, because it's on a non-Microsoft "third party" site. While it's true it's on "windows.net", that's still a Microsoft site, but apparently he's not allowed to access it. Continue reading
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