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Comment Re:Hmm (Score 1) 370

Firewalls are capable of providing all of the positive benefits of NAT (transient traffic flow approval instead of mapping for example, blocking traffic not originated from the LAN, etc) save obfuscating the source address. Obfuscating the source address isn't particularly relevant from an attack perspective given that the entire LAN is still protected by the same Firewall process, NAT or not.

For example: you could NAT your LAN in 192.168.10.x space behind IP 1.2.3.4 .. you connect to shady.com port 80 sport 192.168.10.101:2000, NAT/firewall allocates 1.2.3.4:3000 for you. Shady sees all the traffic coming from 1.2.3.4:3000, but has no way (short of client-side malware) to know that maps to 192.168.10.101; nor can Shady care since all access to 192.168.10.101 is mediated by 1.2.3.4. Shady.com might try to port scan 1.2.3.4, and see any port forwards your entire LAN uses in one swoop, try to exploit them if possible. Moral: make sure you know what you are doing when you port forward.

Or, if you use IPv6 for your LAN, let's say you are allocated 1:2:3::/112. No need to NAT it, so you just firewall behind your gateway, let's say 1:2:3::4. You connect to shady.com port 80, sport [1:2:3::101]:2000. Firewall doesn't have to allocate a damned thing for you, but instead records the flow for [1:2:3::101]:2000 shady.com:80 as established from within the LAN and thus authorized. Shady sees all the traffic coming from [1:2:3::101]:2000, but it's not relevant since all access to 1:2:3::101 is still mediated by the firewall at gateway 1:2:3::4. Shady.com can port scan 1:2:3::101 if it likes, but won't see any open ports if you only allow LAN established traffic, or else sees your whitelisted ports for that IP only (instead of your entire LAN). Just like the IPv4/NAT scenario, keep your open ports secure.

As you can see, source IP obfuscation provides no meaningful advantage to the end user in this scenario. If anything, IPv6 users who feel like they want to use NAT could have the firewall choose random source addresses as well as random source ports out of their /112, and hide their 3 LAN devices within a pool of 65 thousand addresses. Would that not confuse a would-be attacker?

Still, the major drawback to be avoided with NAT is in breaking the globally unique address space and complicating inbound connection access, which will become a growing part of popular network policy over the next few decades. One thing Bit Torrent teaches us is that "the server" will less and less frequently have resources comparable to the "client swarm", so crowdsourcing the heavy lifting (from distribution to content creation to editing to caching) becomes vital to any scaling strategy worth it's salt. The hub/spoke communication model is slowly eroding in the presence of more sophisticated, decentralized many-to-many connection models.

NAT reduces a peer to a "consumer" which can only fetch data, but never re-offer it without convoluted port forwarding messes. Entire LAN's are limited to one named service per outbound IP, unless one wishes to screw with what port they offer services on, further complicating the job for other firewalls and participants of the content network.

You'll know what I mean if you've ever tried to configure mobile SIP access. Half the time you are behind a NAT, and you'll never know in advance if it's full cone, symmetric, or just somehow pathological. Sometimes you are nested within multiple NATs which each behave differently!

Some legacy UDP protocols I've worked with need to make connections to thousands of remote IP addresses at multiple, highly transient port mappings which bring NAT mapping tables to their knees. In a firewall-only environment, it's easy to whitelist access to swaths of ports for clients and then the gateway need not maintain tables for related traffic, but can continue to protect unrelated ports unlike with SOHO DMZ.

To sum up, NAT is not only a bandaid, but it's already pulling at our short-hairs.

Comment Vote 'em Out (Score 1) 198

Members of parliament need to be reminded that they work for us, not Big Media Corp. They need to be reminded that their job security depends heavily on our support, not the support of a corporate lobby group - especially a FOREIGN lobby group. Members of parliament need to become aware that serving the interests of the people whom they represent is their number one priority and serving the interests of lobby groups can come somewhere much further down on that list. They need to be reminded in the simplest and best way possible - they need to be informed that, if they fail to represent the best interests of the people, the people will replace them with someone who understands their role better. They need to be reminded that Big Media Corp might be represented by a large and powerful lobby group but "the population at large" is a much large, much more powerful lobby group and we, as the population at large", are willing to flex our muscles if we aren't being represented properly.

Write to your member of parliament. Vote smart.
Privacy

Company Laptop, My Data — Can They Co-exist? 395

An anonymous reader writes "I recently replaced my old laptop. The owner of my company heard about this and offered to reimburse me for it, since he knows I have and will continue to do company work on my own hardware. I'd like the extra $1,250, but I think if I accept his offer that legally he has the right to any data on it (personal emails, files, blog posts, etc.). Even if I decide to put my personal stuff on a second drive, I'm worried that using company property to save and write to separate storage still gives them the right to it. The apps (Office, etc.) are my own licenses. We do not have a policy that intellectual property developed using company assets belongs to the company. But, if I figured out the One Great Internet Business Idea or write the Great American Novel and used the company laptop to do it, it's an avenue they could use to claim they own it. Unlikely, but scary. How many Slashdotters have been in this situation, and what agreement did you and your management come up with?"
Security

Submission + - How to take a vacation as a one man IT dept? 2

wgoodman writes: I work at a small company as the sole geek. It's been a few years now and I'm forced to actually use some of the vacation time that I've built up otherwise I lose it. Since I'll be gone for a few weeks with no cell phone and only intermittent internet access not to mention nearly constant drunkenness, what precautions and steps to avoid things going south in my absence do you recommend? I've scripted as much as i can of the day to day stuff, got a lackey to swap backup tapes, and given my boss contact info on the equipment that we have support contracts with. What am I forgetting?
Spam

Submission + - Lawsuit shows how to sue spammers (com.com)

mytrip writes: "A recent decision in a lawsuit filed against a Florida credit counseling company offers a promising road map to follow for suing spammers.

An investigation of the sender traced the source back to a business called The Credit Counseling Foundation in Fort Lauderdale, Fla. Hylkema, a Slashdot reader who once had an e-mail address at the aptly named Suespammers.org, filed a lawsuit in Washington claiming that Credit Counseling was spamming in violation of two state laws, and obtained a default judgment when the company never showed up to defend itself.

After receiving at least nine unsolicited e-mail messages offering credit counseling services, Washington state resident Joseph Hylkema did more than just consign the spam to his junk mail folder: he decided to get even.

Washington state law allows for damages of $1,000 per e-mail message. According to an announcement that Hylkema made in March 2002, though, a judge awarded him a default judgment of $31,575."

Science

USAF Developing New "SR-72" Supersonic Spy? 428

Kadin2048 writes "According to an Air Force Times article, the famed Lockheed Martin 'Skunk Works' may be hard at work on a new supersonic spy plane (with 'artist concept') for the U.S. military, to replace the SR-71 'Blackbird' retired a decade ago. Dubbed by some the SR-72, the jet would be unmanned and travel at about 4,000 MPH at as much as 100,000 feet, with 'transcontinental' range. Some have speculated that new high-speed spy planes could be a U.S. response to anti-satellite weapons deployed by China, in order to preserve reconnaissance capabilities in the event of a loss of satellite coverage. Neither the Air Force nor Lockheed Martin would comment on the program, or lack thereof."
Spam

Submission + - Where does a sysadmin go for help?

An anonymous reader writes: I believe I have stumbled up a new FreeBSD based rootkit/hack/backdoor/whatever you want to call it. I'm pretty sure I know how it was installed on the server, I've got a pretty good idea of how most of it works, but there are parts that are over my head. I am not an idiot, but I am lacking the reverse engineer skills required to see exactly how it works. I am leery about posting my findings to a public forum because the last thing I want to do is give the script kiddies a new toy to play with without having full knowledge of how it works myself. I would prefer to disclose what I've found to a trustworthy third party who can elaborate on my findings and then have the findings posted publicly should this turn out to be something new. Please keep in mind I have googled, yahooed, searched forums, searched usenet for any mention of what I have found and have come up empty handed. It's entirely possible this is nothing new, and I am a n00b, but in either case my question is: where does a sysadmin go when he doesn't have and can't find an answer? PS: I am already aware that in Soviet Russia, answer finds you. Unfortunately I don't live in Soviet Russia. :(
Space

Black Hole Information Loss Paradox Solution Proposed 252

Anuborn Satirak writes to tell us that Physicists from Case Western Reserve University claim to have cracked the black hole information loss paradox that has puzzled physicists for the past 40 years. "The physicists are quick to assure astronomers and astrophysicists that what is observed in gravity pulling masses together still holds true, but what is controversial about the new finding is that 'from an external viewer's point it takes an infinite amount of time to form an event horizon and that the clock for the objects falling into the black hole appears to slow down to zero,' said Krauss, director of Case's Center for Education and Research in Cosmology."
Displays

Submission + - Dell replacing faulty LCD screens

An anonymous reader writes: Dell responds to customers who created a Web site to complain that some LCD screens developed a one pixel-wide vertical line by offering free replacements of the displays. According to the Web site, unless a faulty LCD screen is replaced, it can develop a permanent vertical line one pixel wide, either stuck on a single color or reflecting the color displayed behind it. ell first responded to the issue in April, offering to replace certain 17-inch displays on Inspiron 9200, Inspiron 9300 and XPS Gen 2 notebooks sold between November 2004 and October 2006. On Tuesday, Dell expanded its replacement program to include six more models, including the Inspiron 6000 and 8600, Latitude D800 and D810, and Precision Mobile Workstation M60 and M70 notebooks sold between December 2004 and December 2006. Some of those models use a faulty component that can generate the line over time, according to a posting on Dell's corporate blog by Lionel Menchaca, Dell's digital media manager. Dell will now replace any LCD screen affected by this issue within three years of purchase, or will refund customers who were forced to pay for their own replacements, Menchaca said.
Microsoft

Submission + - Microsoft flip-flopping on virtualization license

Cole writes: Microsoft came within a few hours of reversing its EULA-based ban on the virtualization of Vista Basic and Premium, only to cancel the announcement at the last minute, Ars reports. The company reached out to media and bloggers about the announcement and was ready to celebrate "user choice" before pulling the plug, apparently clinging to security excuses. From the article, "The threat of hypervisor malware affects Ultimate and Business editions just as much as Home Premium and Basic. As such, the only logical explanation is that Microsoft is using pricing to discourage users from virtualizing those OSes. Since when is a price tag an effective means of combating malware?" Something else must be going on here.
Displays

Submission + - NVIDIA Launches Tesla Brand for GPGPU (beyond3d.com)

An anonymous reader writes: Today, NVIDIA launched the Tesla brand of products. Using the same GPUs found in the GeForce series, these cards can accelerate workloads written in CUDA, NVIDIA's GPU programming language. Beyond3D has an overview at what these products are (including the 1U rackmount with 4 GeForce 8800 chips in it), what they can currently do, and what the future of the GPGPU market is. They also have interviews with David Kirk, chief scientist of NVIDIA, and Andy Keane, manager for the Tesla brand.

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