GeekNights 20110228 - Model Rocketry

MrPeriod

Tonight on GeekNights, we talk a bit about model rocketry and its merits as a teaching tool. In the news, Thunderbolt takes flight, and Craigslist is a den of iniquity (according to people who have a vested interest in it failing).

You might also want to go vote (for Rainbow Dash).

• Rym's Thing - Lewis and Clark's Air Rifle
• Scott's Thing - "Smack My Bitch Up" by The Beatles

Download MP3

Coldguy

How in the world has Rym never heard of Smack my Bitch up before? Plus I do agree that model rocketry is more of a hobby rather then a means to educate about science, which is the ultimate downfall of the rocketry in my opinion.

Luke Burrage

"What are you, a rocket scientist?"

The Smack My Bitch Up is one of the funniest things I've seen in ages. I was almost in tears.

Relevant (rockets are less dangerous than remote control cars):



PS. Explaining jokes is part of the fun.

Rym

How in the world has Rym never heard of Smack my Bitch up before?

It's a meh song, and I never particularly liked Prodigy. Not disliked, but not liked either.

Dragonmaster Lou

BTW, Thunderbolt is not an Apple thing. It's actually an Intel thing that Apple happened to be the first to jump on for whatever reason. It's the marketing name for Intel's interface that used to be known by the code name "Light Peak."

Apreche

BTW, Thunderbolt is not an Apple thing. It's actually an Intel thing that Apple happened to be the first to jump on for whatever reason. It's the marketing name for Intel's interface that used to be known by the code name "Light Peak."

I thought light peak was optical? I don't think the thunderbolt is optical, is it?

Churba

I thought light peak was optical? I don't think the thunderbolt is optical, is it?

Quoth The wiki article

The interface was originally designed to use flexible optical fiber cables, but a version using conventional copper wiring was also developed to furnish the desired 10 Gb/s bandwidth at less cost.

Dragonmaster Lou

Yeah, Light Peak is kind of like Fibrechannel in that regard. Fibrechannel is primarily optical, but it uses copper for short enough runs for cost reasons. For example, every enterprise-grade RAID system I've worked with that used Fibrechannel for its internal drives used copper for the short-distance internal interconnect but went optical for the longer external connections.

Apreche

Yeah, Light Peak is kind of like Fibrechannel in that regard. Fibrechannel is primarily optical, but it uses copper for short enough runs for cost reasons. For example, every enterprise-grade RAID system I've worked with that used Fibrechannel for its internal drives used copper for the short-distance internal interconnect but went optical for the longer external connections.

Does light peak over copper have a short max cable length? If it's too short, that could be a problem if you want to hook your MacBook up to the RAID for video editing, but the RAID isn't on your desk.

Jason

Yeah, Light Peak is kind of like Fibrechannel in that regard. Fibrechannel is primarily optical, but it uses copper for short enough runs for cost reasons. For example, every enterprise-grade RAID system I've worked with that used Fibrechannel for its internal drives used copper for the short-distance internal interconnect but went optical for the longer external connections.

Forgive the noob question, but what's the point of having fiber if you're going to corrupt it with copper jumps? Isn't the whole system as slow as its slowest medium?

Rym

Forgive the noob question, but what's the point of having fiber if you're going to corrupt it with copper jumps? Isn't the whole system as slow as its slowest medium?

Fiber isn't faster, it's longer-range.

Dr. Timo

Thunderbolt currently is 20Gb/s in both directions (only 10Gb/s for data). I have read that once optical transceivers become cheap enough Intel will come out with cables that have the transceivers embedded into the plug thus making the optical cables backwards compatible with copper connectors (I doubt that they will even make optical connectors).

Dragonmaster Lou

Yeah, Light Peak is kind of like Fibrechannel in that regard. Fibrechannel is primarily optical, but it uses copper for short enough runs for cost reasons. For example, every enterprise-grade RAID system I've worked with that used Fibrechannel for its internal drives used copper for the short-distance internal interconnect but went optical for the longer external connections.

Does light peak over copper have a short max cable length? If it's too short, that could be a problem if you want to hook your MacBook up to the RAID for video editing, but the RAID isn't on your desk.

According to this PDF on Intel's site, the copper range is 3 meters and can deliver up to 10W of power. The PDF only lists the optical distance as "tens of meters," however.

Interestingly, Thunderbolt itself uses DisplayPort's protocol for video and PCI Express for everything else. The PDF claims that it should be easy enough to make Thunderbolt adapters for USB, Firewire, etc., by simply using existing PCI Express components.

Victor Frost

Forgive the noob question, but what's the point of having fiber if you're going to corrupt it with copper jumps? Isn't the whole system as slow as its slowest medium?

Fiber isn't faster, it's longer-range.

Fuck yes. We currently run fiber between our SANS and between major servers across our two server rooms. Between the server rooms is much longer pull than anything cat 6 could ever handle. Fiber for the win.

Jack Draigo

Only time I shot off rockets was at boy scout camp. Found mine but a lot of guys lost their in the woods. It was a lot of fun though.

Dragonmaster Lou

Forgive the noob question, but what's the point of having fiber if you're going to corrupt it with copper jumps? Isn't the whole system as slow as its slowest medium?

Fiber isn't faster, it's longer-range.

Fuck yes. We currently run fiber between our SANS and between major servers across our two server rooms. Between the server rooms is much longer pull than anything cat 6 could ever handle. Fiber for the win.

Plus, in most enterprise RAIDs (at least EMC's and NetApp's, which are the ones I've had experience with), you aren't touching the physical disks inside the systems anyway. All that stuff tends to be somewhat abstracted and you're really reading/writing from the arrays' cache RAM. Even if copper was slower than Fibre, the user is never directly hitting the copper anyway. Back around 2000 or so, even EMC's highest end arrays (the Symmetrix 8000 series) were still using parallel SCSI for its internal drive connectors despite having external Fibre connectivity, and they were still pretty damned fast thanks to having some ridiculous for the time amount of cache (I think it topped out at 128 or 256 GB, but it's been a while -- the next gen after the 8000s topped out at 512 GB, but that one had switched to internal Fibre connectivity as well).