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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. :-)

Comment It's all up to you (Score 1) 266

Speaking for myself, I've been in IT as a Unix sysadm and a Networking guy since 1988, and I have no college degree, and a night school HS diploma. I'm completely self taught. However, my background as a programmer hobbyist since age thirteen helped a lot here. I likely was a better programmer with more real world experience than the average CS grad by the time I was sixteen, having put out a few shareware programs.

My entry to my first IT job came directly from attending a local Amiga users group meeting. I was showing off some program I wrote, and one of the guys there happened to work for my future employer (a well known Govt agency), and set me up with a sort of internship. And it was actually for more money than I ever made before, and quite a good salary for someone in their early 20s.

So I reiterate some of the other posters advice. Go to users group meetings, and teach yourself stuff. Today, the opportunities for self instruction are WAY better than they were for me back in the early 80s. Back then, I had an 8 bit computer and a few books I had to mail order to help me learn. Today, we have the internet with a vast array of free software and web sites with free tutorials and references everywhere, as well as free visualization software to allow you to explore different OSes, etc. There are pretty much endless opportunities to help learn on the web today.

Just about any degree, even a liberal arts one, is better than no degree for employ-ability. So don't worry about that. I've actually met many extremely good programmers and sysadmins with totally unrelated degrees.

Comment Re:Doesn't work in the US (Score 1) 368

LOL. Generalize much? Maybe this is your experience, but from my experience Americans hang out with each other as much as any other culture. I know it can be ... er ... trendy (?) to bash Americans and American culture (even in many American circles), but if you're going to do it, at least pick something that's true.

Comment Re:All the real action was on BBSes. (Score 1) 387

Yep. I was one of these users. I had a TRS-80 Coco and an Amiga, and although I was on services like Compu$erv and GENIE (anyone remember that?), the lions share of my time was on private BBSes, typically in the local calling area.

It was the "social networking" of the era, since most of the local BBSes had fairly frequent get-togethers. We had parties, scavenger hunts, gatherings where we just had some good food and brought our computers to play games (sort of like a LAN party) or show off some new hardware or software (which we often wrote ourselves).

In my case, I got into the IT industry via one of these gatherings, where we got together weekly to drink some home-brew beer, eat some good food, hang out, etc. I was showing off a piece of software I wrote on the Amiga, and it happened that one of the regular attendees was looking for an IT intern, and basically hired me on the spot.

Also, we can't forget about UseNet, which I see as a sort of grandparent to things like Facebook, etc. :-)

Unlike the OP, I found those times to be a bit more ... civil? ... than today's Internet. The online universe of that day was populated mostly by a bunch of geek types. The way I remember it, things didn't take the turn to what we have today until Joe 6-Pack showed up online.

Comment "Gravely voiced girl" (Score 1) 331

Is this the same thing you hear in many advertisements directed at a female demographic? I've always referred to it in my head as "the gravely voiced girl". It almost sounds like they hire the same voice over person to do "that voice" for lots of different ads (actually wouldn't surprise me much). I'm glad I'm not the only one to have noticed this. :-p

Comment Re:Why Gen Z Needs To Change for Work (Score 1) 443

Sorry, no matter what the generation, they should not be allowed to bring more attack vectors and security vulnerabilities in to the workplace.

They are not special snowflakes, and their personal devices are not necessary for productivity.

Businesses where mobile devices are useful and helpful should already have their infrastructures designed to handle it, so again Gen Z will make no difference.

Hear hear. If they're to be given access to anything, it should be some sort of guest WLAN with internet access only, and heavily firewalled VPN only access to the corporate net, if any. End users simply can't be trusted to keep their personal devices secure. It's hard enough to assure this with their corporate assigned hardware.

Many business, especially regulated ones (SOX, FDA, HIPPA regulated, etc) don't allow personal devices to be plugged into the network at all, and it is a serious breach of policy to do so which could result in termination.

Comment Re:This is ridiculous (Score 1) 214

IPv4 thinking is going to be hard to break. :)

Here's the relevant section of that RFC:

3. Address Delegation Recommendations

      The IESG and the IAB recommend the allocations for the boundary
      between the public and the private topology to follow those general
      rules:

            - /48 in the general case, except for very large subscribers.
            - /64 when it is known that one and only one subnet is needed by
                  design.
            - /128 when it is absolutely known that one and only one device
                  is connecting.

      In particular, we recommend:

            - Home network subscribers, connecting through on-demand or
                  always-on connections should receive a /48.
            - Small and large enterprises should receive a /48.
            - Very large subscribers could receive a /47 or slightly shorter
                  prefix, or multiple /48's.
            - Mobile networks, such as vehicles or mobile phones with an
                  additional network interface (such as bluetooth or 802.11b)
                  should receive a static /64 prefix to allow the connection of
                  multiple devices through one subnet.
            - A single PC, with no additional need to subnet, dialing-up from
                  a hotel room may receive its /128 IPv6 address for a PPP style
                  connection as part of a /64 prefix.

      Note that there seems to be little benefit in not giving a /48 if
      future growth is anticipated. In the following, we give the
      arguments for a uniform use of /48 and then demonstrate that it is
      entirely compatible with responsible stewardship of the total IPv6
      address space.

So it will actually be fairly common for end users to get a /48, or 64Ki /64s. Businesses will likely get a /48 per-site. :)

Comment Re:Mac Issue Or IPv6 Issue? (Score 1) 204

It's really the combination two problems. 1) The particular OS is configured to prefer 6to4 connectivity to native IPv4, 2) 6to4 isn't supported well on many ISPs for various reasons, and there can also be LAN issues which make 6to4 not work well, or at all. So you could say #2 here is a problem with 6to4 implementation.

Most OSes by default (Windows, and most distros of Linuxes, and BSDs) are configured to prefer using a native IPv4 address before an IPv6 6to4 or Teredo (another automatic tunneling method) address (see RFC 3484) for connections. Apparently OS X isn't. So, when a site has both an IPv4 and an IPv6 address, OS X will prefer the IPv6 address even if the system's IPv6 connectivity is via 6to4. Since 6to4 is often slow, slow to start, or just plain doesn't work on a particular LAN/ISP depending on a plethora of reasons, you'll get timeouts and such. This is one of the reasons why services like Google have a separate domain name for IPv6 based services (ipv6.google.com), instead of just putting up both A and AAAA DNS records.

If using a 6to4 connection, YMMV depending on your LAN configuration, your ISP, routes it receives, proximity to a 6to4 relay, whether the 6to4 anycast address (192.88.99.1) your ISP sees routes to a reasonable place, etc. This is why it's so problematic. There are a lot of variables which can make it either not work at all, or affect its performance. Plus, being a tunneling scheme, performance is already degraded vs. a "native" protocol even if it worked perfectly.

6to4 works by constructing an IPv6 address in a special range reserved for it (2002::/16) which encodes your IPv4 address into the IPv6 address (i.e. if your IPv4 is 192.0.2.10, the 6to4 IPv6 prefix will be 2002:c000:20a::/48, out of which you can subnet and make /64s, etc). The traffic is then sent over a IPv4 6in4 (IPv4 protocol 41) tunnel to the "nearest" 6to4 relay which is reached via the 6to4 anycast address (unless the relay server is configured manually). Unfortunately, many ISPs have this anycast routed to a far away relay. For instance, two friends' separate cable ISPs I tested this on had the traffic routing from eastern Canada and the western USA to a relay server in Sweden!

Traffic from the IPv6 internet to the 6to4 space is routed from its source to the "closest" relay server advertising the 6to4 space in BGP. The relay extracts the IPv4 address from the 6to4 IPv6, and the IPv6 packet is encapsulated in a IPv4 6in4 tunnel packet and sent to the extracted IPv4, which should be the user's 6to4 router. This trip from the origin to the 6to4 relay can also often be a long distance, depending on the origin of the traffic, and then of course the tunnel packets have to make their way over the IPv4 internet to your 6to4 router. Obviously this can make for some pretty serious asymmetric routing which can cause its own problems.

Other problems such as 6in4 being blocked anywhere along the forward or reverse path to the user's 6to4 router will cause it to fail. Also, if the implementation isn't smart enough to know that a particular box is behind a NAT, and constructs a 6to4 IPv6 address based on the NATed address instead of the public IPv4, it will obviously fail, since the return traffic will be sent to a private IPv4 address by the relay server instead of the user's public. I don't know if OS X does this or not. And finally, most firewall/nat boxes with a single public IP shared by many computers can only support a single 6in4 (and therefor 6to4) tunnel behind them, since unless they inspect and track the tunneled IPv6 packets (plus some other implementation enhancements), there's no way it can know which inside host to send return traffic to when it deNATs them.

Note, that none of this is a basic failing of IPv6! The problems here are with implementation details of a well intentioned automatic tunneling method designed to provide IPv6 access to IPv4 only users in a "automatic" manner which doesn't require much user knowledge or intervention. Unfortunately, it didn't "work as intended" based on some of the factors I mentioned above, plus probably others I haven't thought of. :-)

This should explain the problem as well as I understand it. Hope it wasn't too boring. :p

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