Tuesday, May 11, 2010

May 2 - Warning: Why your Internet might fail on May 5‏

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Warning: Why your Internet might fail on May 5

Apr 30, 2010 12:16 PM

Network operators urged to check routers, firewalls.

Network managers are being urged to run a series of checks on their routers and firewalls to ensure their users will still be able to connect to internet sites in the wake of a major change to the

internet's domain name system next week.

On May 5, the world's top domain authorities (led by ICANN, the US Government and Verisign) will complete the first phase of the roll-out of DNSSEC (Domain Name System Security Extensions) across the 13 root servers that direct user requests to the relevant websites on the internet.

The DNSSEC upgrade adds a digital signature to the response from every DNS (Domain Name Server) request to give an internet user an extra level of assurance that the domain name is translated to the correct Internet location (such as a website, or email destination).

DNSSEC was developed in an attempt to thwart 'man in the middle' attacks, in which hackers intercept a request and respond with a message that fools the user system into going to a false location. But the new protocol - much welcomed by the industry - could have an unfortunate side effect for unprepared network managers, according to Bruce Tonkin, chief strategy officer at Melbourne IT and a board director at ICANN.

But the new protocol - much welcomed by the industry - could have an unfortunate side effect for unprepared network managers, according to Bruce Tonkin, chief strategy officer at Melbourne IT and a board director at ICANN.

A response to a standard DNS request tends to be in a single packet (UDP protocol) and tends to fall below 512 bytes in size.

In some older networking equipment, any larger request than this would be blocked by pre-configured factory settings, under the assumption that larger packets (and several of them) represent an anomaly of some kind.

As of May 5 at 17:00 UTC (which is actually pre-dawn on Thursday 6th on the East Coast of Australia), all DNSSEC signature-laden messages sent back to a user's DNS resolver will be four times the size - up to 2 KB. And should packets of that size be rejected, the message would likely be sent in multiple packets via the TCP protocol.

(These signatures will be dummies at first to test the system, as of July 1, they will be the real deal.)

Tonkin fears that while DNSSEC has been on the agenda for some time, many IT and network managers have yet to test their older routers and firewalls to ensure they can handle the larger DNS responses.

"The bigger answer coming back from the DNS request might get blocked by some internet devices in the Corporate network," he said.

DNSSEC is in fact already rolled out across most of the world's 13 root server clusters, in an effort that began in December 2009.

But to date, Tonkin explained, it would only have resulted in a slight lag in the loading of a web page for those with outdated network equipment.

The beauty of DNS is that should a request made to one root server not receive a response, the DNS resolver on a user's machine simply makes the same request along the line of the 13 root servers until it gets a satisfactory response.

But on May 5, once all 13 root server clusters are live with the DNSSEC signatures, responses from all 13 root servers won't make it back inside the corporate LAN on some older systems.

Tonkin expects that the larger Internet Service Providers will have addressed the issue, so most home internet users will be unaffected.

"I'm not entirely sure all ISPs will be prepared, but I imagine the major ones are," he said. "ISPs tend to do DNS translation for you. But it is likely to have a big impact in the corporate environment, where you might run your own DNS server and infrastructure."

In that sense Tonkin doesn't expect a "Y2K meltdown" of the internet May 5.

But he predicts a number of organisations will start experiencing internet access issues, and a number of network administrators will be left scratching their heads as to why.

To complicate the scenario further, network administrators and helpdesks "may not know what has gone wrong," he said.

The problem may take several days to surface and be inconsistent from one user's PC to the next. A user at one machine that hasn't switched on his PC for two or three days will have no access to the internet. A user that left his machine on the night before will have some pages - and responses from DNS servers - cached on their machine, and will still have connectivity.

"It is usually much easier to address a problem when everything isn't working!" Tonkin said.

Tonkin recommended network managers run a series of simple online tests to ensure their network can handle the larger DNS responses:

- A reply-size test available at DNS-OARC:

- Ripe Labs' 'Test your DNS Resolver'

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How to Digitally Record/Video a UFO sighting:

Como registar digitalmente ou gravar um vídeo de um avistamento de um UFO:

Stabilize the camera on a tripod. If there is no tripod, then set it on top of a stable, flat surface. If that is not possible lean against a wall to stabilize your body and prevent the camera from filming in a shaky, unsteady manner.

Estabilize a camera com um tripé. Se não tiver um tripé, então coloque-a em cima de uma superfície estável. Se não for possível, então encoste-se a uma parede para estabilizar o corpo e evitar que a camera registe de maneira tremida e instável.

Provide visual reference points for comparison. This includes the horizon, treetops, lampposts, houses, and geographical landmarks (i.e., Horsetooth Reservoir, Mt. Adams, etc.) Provide this in the video whenever is appropriate and doesn’t detract from what your focus is, the UFO.

Forneça pontos visuais de referência para comparação. Isso inclui o horizonte, cimo das árvores, postes de iluminação, pontos de referência geográficos (como o Reservatório de Horsetooth, Mone Adams, etc) Forneça esses pontos no vídeo sempre que for apropriado e não se distraia do que é o seu foco, o UFO/a Nave.

Narrate your videotape. Provide details of the date, time, location, and direction (N,S,E,W) you are looking in. Provide your observations on the weather, including approximate temperature, windspeed, any visible cloud cover or noticeable weather anomalies or events. Narrate on the shape, size, color, movements, approximate altitude of the UFO, etc and what it appears to be doing. Also include any unusual physical, psychological or emotional sensations you might have. Narrate any visual reference points on camera so they correlate with what the viewer will see, and thereby will be better able to understand.

Faça a narração do vídeo. Forneça pormenores sobre a data, hora, local e direcção (Norte, Sul, Este, Oeste) que está a observar. Faça observações sobre as condições atmosféricas, incluindo a temperatura aproximada, velocidade do vento, quantidade de nuvens, anomalias ou acontecimentos meteorológicos evidentes. Descreva a forma, o tamanho, a cor, os movimentos, a altitude aproximada onde se encontra o UFO/nave, etc e o que aparenta estar a fazer. Inclua também quaisquer aspectos pouco habituais de sensações físicas, psicológicas ou emocionais que possa ter. Faça a narração de todos os pontos de referência visual que o espectador irá ver e que, deste modo, será capaz de compreender melhor.

Be persistent and consistent. Return to the scene to videotape and record at this same location. If you have been successful once, the UFO sightings may be occurring in this region regularly, perhaps for specific reasons unknown, and you may be successful again. You may also wish to return to the same location at a different time of day (daylight hours) for better orientation and reference. Film just a minute or two under “normal” circumstances for comparison. Write down what you remember immediately after. As soon as you are done recording the experience/event, immediately write down your impressions, memories, thoughts, emotions, etc. so it is on the record in writing. If there were other witnesses, have them independently record their own impressions, thoughts, etc. Include in this exercise any drawings, sketches, or diagrams. Make sure you date and sign your documentation.

Seja persistente e não contraditório. Volte ao local da cena e registe o mesmo local. Se foi bem sucedido uma vez, pode ser que nessa região ocorram avistamentos de UFOs/naves com regularidade, talvez por razões específicas desconhecidas, e talvez possa ser novamente bem sucedido. Pode também desejar voltar ao mesmo lugar a horas diferentes do dia (durante as horas de luz)para ter uma orientação e referência melhor. Filme apenas um ,inuto ou dois em circunstâncias “normais” para ter um termo de comparação. Escreva tudo o que viu imediatamente após o acontecimento. Logo após ter feito o registo da experiência/acontecimento, escreva imediatamente as impressões, memórias, pensamentos, emoções, etc para que fiquem registadas por escrito. Se houver outras testemunhas, peça-lhes para registar independentemente as suas próprias impressões, pensamentos, etc. Inclua quaisquer desenhos, esbolos, diagramas. Certifique-se que data e assina o seu documento/testemunho.

Always be prepared. Have a digital camera or better yet a video camera with you, charged and ready to go, at all times. Make sure you know how to use your camera (and your cell phone video/photo camera) quickly and properly. These events can occur suddenly, unexpectedly, and often quite randomly, so you will need to be prepared.

Esteja sempre preparado, Tenha sempre uma camera digital, melhor ainda, uma camera vídeo consigo, carregada e pronta a usar sempre que necessário. Certifique-se que sabe como lidar com a sua camera (ou com o seu celular/camera fotográfica) rápida e adequadamente. Esses acontecimentos podem acontecer súbita e inesperadamente e, por vezes, acidentalmente, por isso, necessita estar preparado.

Look up. Be prepared. Report. Share.

Olhe para cima, Esteja preparado, Relate, Partilhe.



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What time is Around the World?


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