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Comment Don't Panic! (Score 4, Informative) 250

Don't Panic, or be afraid of IPv6.

People often talk of "switching" to IPv6. One does not "switch". You simply deploy it alongside IPv4. Right now my home network is happily running IPv4 and IPv6 at the same time, called a "dual-stack" environment. This sort of set up will be common for decades until IPv4 use dwindles to nothing, and people start turning it off.

Nearly all operating systems and devices supporting IPv6 have it turned on by default, so you're already running IPv6. You just don't have globally routable addresses assigned (most likely). You could actually use ping (windows) and ping6 (*nix) to ping other hosts on your LAN using link local addresses, which have automatically been assigned (see those addresses starting with fe80 on all of your interfaces?), if you knew how, right now. :-)

If you know IPv4 routing and subnetting, you already know most of what you need to know about IPv6. Except that IPv6 is simpler since there's no need to NAT. Just set up your firewall exactly as you would under IPv4 (same security policy), minus the NAT. Subnetting is also simpler, with no need to fret over "right sizing" your subnets so they're "just big enough" and don't use too much of your precious IPv4 space. Just assign a /64 out of your /48 (businesses will be easily be able to request multiple /48s) and you're done. Never run out of host numbers, or subnets.

Some folks are frightened by the use of hexadecimal for IPv6 addresses. No need to fret. It makes sense, and would have made sense for IPv4 also. Hex for IPv6 not only makes the IPv6 addresses more compact., it's also far easier to translate hex into binary, and work with prefix-lengths than decimal IPv4 address are. I can do it in my head all day with no issue. All you have to do is memorize 16 bin patterns from 0000 to 1111, each represents a hex digit from 0 - F. Piece of cake. No more annoying math and base conversion to try to figure out which subnet some IPv6 address belongs to like with IPv4. No more subnet masks either (which are also decimal), instead, just prefix lengths (although this is also true of IPv4 with CIDR, adopted long ago, many user interfaces still require a netmask for IPv4 instead of just a /prefix-length, sigh).

Anyway. Go play with IPv6. It will be an essential skill to add to your Resume/CV, and will only take a short time to figure out. Go set up an tunnel with Hurricane Electric or some other tunnel broker to get some globally routable IPv6s. It's simple and you'll learn a lot and quickly! And best of all, you'll stop being afraid of IPv6! :-)

(apologies to those who already have adopted IPv6 and know all this already ... this isn't addressed to you!)

Comment Re:So after years of panic... (Score 1) 250

It's Layer 3 and Layer 2, not Level. Also, the point of IPv6 was not to bring L2 & L3 closer together. It just happens that automatically configured IPv6 addresses (link local, SLAAC addresses) use the MAC address by default to form addresses. One is free to pick any host number on your subnet, just like IPv4.

In fact, in most ways you can really look at IPv6 as IPv4 with bigger addresses. Subnetting and routing works the same, etc. It just has a lot of nice new features, and efficiency boosts that were adopted based on our experience with IPv4. For instance, some header fields in IPv4 have been removed and moved to options trailers. This is why an IPv6 header is the same length as an IPv4 header even with address fields 4X larger. There is no more broadcast address, since everything uses multicast. Subnetting is also simplified by the standard imposed by SLAAC of a LAN being a /64, and the easy availability of large blocks of IPv6 network space. Most businesses will get a /48 per site, which gives 64K subnets to work with each. Comcast residential customers are apparently being assigned /60s, which provides 16 subnets, and business customers are getting /56s which allows 256. Imagine that. Your home ISP giving you routable subnets with no NAT required. :)

Comment Re:Comcast and ipv6 (Score 1) 574

Yep. Residential is getting /60s AFAIK. I'm part of the Comcast business trials and they're delegating /56 subnets to biz customers at this point. We're presenting working out some firmware issues with DHCPv6-PD (Prefix Delegation) so that we can get my router/FW talking to their CPE router and start dolling out subnets.

Comment Is it such a bad comparison? (Score 1) 683

It wouldn't surprise me at all if these protests against the bus programs ultimately erupt into violence, damaging property, terrifying the passengers, and perhaps even resulting in injury or death.

To a Google or other bussed employee, broken glass of a bus window would probably invoke similar fears to those felt by the persecuted of Nazi Germany when their shop windows were broken. Would it not?

Violence is a very under-reported fact of the Occupy movement. There were more than a few injuries, fights, and lots of property damage, including, incidentally, broken shop windows.

These are likely the sorts of thoughts that provoked Perkin's Op-Ed.

Globalization, a changing economy, and class warfare promulgated by the politically "Progressive/Liberal" are what is spurring these sorts of protests and actions. Obstructing buses, picketing employees homes, etc.

And the folks doing the bus thing aren't by any means "1%ers". Which is probably why Perkins put that term in quotes. They are basically middle and upper middle class folks.

Regardless of the validity of the protestors' position and beliefs, the sorts of actions they've been taking are troubling.

Sure. Gentrification would suck if you are being forced out of your place of residence by rising rents. But is it really right to blame folks for the effects of supply and demand?

Anyway, I'm sure the primary goal for these protests is to try to cajole the government into some sort of action, such as rent control, or some other artificial means of keeping rents down. Whether that is fair or not is the subject of a separate debate. I just hope the so called "99%ers" don't take things any farther than they have already.

Comment How do "progressive" Googlers feel about this? (Score 1) 683

Given the general demographics of the SF Bay Area, I presume there are many Google employees who identify as "Liberal" or "Progressive".

I'm wondering how Googlers feel now that many of them are the targets of this sort of protest?

From a Googlers perspective, they're simply taking a bus ride to work. This allows them to relax, and be productive and get some work done instead of sitting in horrific Bay Area traffic for an hour or more. It's a win for both employee and employer. Is it not also the ultimate form of carpooling, an environmentalist win? Is not carpooling and HOV lanes something championed and endorsed and often claimed as an exclusive province of the left?

It's quite the tangle of conflicting leftist ideas, no?

BTW, I'm not a Googler. I have my own issues with Googler having to do with anti-2A policies, which pretty much prevents me from considering employment there, despite semi-frequent contact by their recruiters.

Comment KISS: Try a fan (Score 2) 474

Keep It Simple Stupid :-)

I'm fairly sensitive to outside noise, and my solution for years has been a simple electric fan. It generates plenty of local white noise which drowns out all the noise from outside.

Works great with no need for parabolic reflectors or active noise cancellation or anything else that might require a DARPA research project. :-)

You cannot have a science without measurement. -- R. W. Hamming