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A Firewall for Every Occasion

Few people in the world would disagree that a network firewall is an essential component for any size datacenter. In fact, operating without one could be considered by many to be network asset suicide! But adding a firewall to an existing datacenter is by no means a trivial task. In fact, the amount of work that would be required to re-cable every physical interface to properly tie it in with the rest of the network is enough to make many network administrators think twice about just how badly they really need that shiny new firewall, versus just sticking with what they have. Add to that the additional rack space, power, cooling, and management required by the new device, and some serious ROI questions may be raised.

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Throwaway Culture Can Help Your Security

Today many organizations find themselves addressing concerns over their proprietary information being stolen and their systems being compromised. Some may view this as a single problem since, in most cases, system compromise is an overture to information theft. The most common ways in which computers are compromised include visiting a web site with malicious content, opening a harmful file — malicious or otherwise — attached to an e-mail message, running a program of dubious provenance and clicking the “yes” button on every message that pops up on the screen. Organizations are fighting back by installing virus scanners, blocking known malicious web sites, filtering incoming e-mail and locking down (aka “hardening”) operating systems as much as possible. But let us take a step back and think about this whole situation again.

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Cryptographic Algorithm Transitions (2010-2011)

Cryptography has been, and continues to be, the most important and ubiquitous aspect of security services (firewall, secure access, VPN, authentication). There is a vast number of cryptographic algorithms and techniques that provide information security features that are used in different protocols and functions. It is important to be able to understand the challenges, attacks, and concerns of cryptographic algorithms in order to be able to use them efficiently. Just as important is the ability to follow the latest developments in the field so that we can be “as secure as possible.” This post is trying to present the latest transformations in the cryptography field to raise awareness on what the status quo is on recommended algorithms and key sizes.

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Cisco CSIRT on Advanced Persistent Threat

For corporations, Advanced Persistent Threat (APT) is a widely publicized yet little understood topic.  Does it exist?  Is it a real threat?  How can an organization tell if it is impacted?

The Cisco Computer Security Incident Response Team (CSIRT) is a global team of information security professionals responsible for the 24/7 monitoring, investigation and response to cyber security incidents for Cisco-owned businesses. CSIRT engages in proactive threat assessment, mitigation planning, incident detection and response, incident trending with analysis, and the development of security architecture. This article will provide the Cisco CSIRT team’s perspective on APT, and is the fifth in a series of blog posts on related issues from CSIRT’s point of view.  As with the other posts, provided here are some real-world examples and techniques that will hopefully help organizations utilize existing tools and processes, or even understand gaps in security infrastructure.  Read on to find out more.

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IPv6 Addressing

In the previous installment of our series of IPv6 posts, we covered some of the ways ICMP has changed in IPv6 compared to IPv4. In this post, we’ll talk about how addressing has changed in IPv6 compared to IPv4.

While IPv4 addresses are 32 bits log, the IPv6 address space has been extended to 128 bits, which will make it virtually impossible to remember the numeric representation of the address for a given host. This will definitely lead to more reliance on DNS. It will be difficult to operate even very simple test networks  without relying on DNS to resolve host names to IPv6 addresses. Because of this, more attacks will be targeted against your DNS servers. Making sure your DNS configuration and servers are secure will be very more important in IPv6. DNS will also be targeted by attackers to attempt to locate systems on the network by trying to resolve “common host names,” since scanning a remote IPv6 network is essentially impossible due to the size of the IPv6 address space.

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