In my previous post re LAN traffic at the University of Venice, I just realized a mistake I'd made. (Funny how time plays with your memory.) The entire university was NOT one giant collision domain! When I first started working there the university was spread-out in temporary offices all around the city; a new campus was under construction. So, many of the departments were linked by routers and ISDN lines. The problematic LAN was limited to the departments/buildings that were directly linked to the main computer center. Still, this was enough users that those departments' Novell servers showed enormous statistics for lost packets.
And, of course, my primary point still remains -- that switches rendered moot the old argument about NIC design.
Friday, September 19, 2008
Sunday, September 14, 2008
The forgotten historical effect of switches
I had a funny little chain of thoughts the other day. I was thinking about how my office's Ghost software (which we use to do disk imaging across the network) uses an old-style packet driver for the network boot disk. Most of my younger counterparts have never seen anything like it, but these drivers used to be quite common. I can remember configuring them for the various DOS-era networking clients waay back in the 1990's. Thinking about this also reminded me about how much effort used to go into designing networks so as to minimize collisions.
I used to work for the University of Venice (Italy!) and their entire campus was setup as ONE big collision domain -- every building was tied directly together and everyone had trouble with lost connections... imagine :-) At the end of my stay there, I suggested to the IT Center that they install a switch at the central hub. At the time, this was considered an extravagance. I explained to them how I'd been going around to all their Novell servers, upgrading the LAN drivers to make them more resilient to ethernet traffic. I think they subsequently used my suggestion ("Our American consultant said...") to justify the expense and I'm sure it was well worth it. Now, of course, switches are The Standard and it's hard to find an old-style dumb hub, and consequently there's no cost premium for it. (P.S. I'm assuming my reader already knows the difference between a hub and a switch?)
Well, the final thought I had was about the problems we used to deal with on hubs. First of all, there was a lot of research into how many workstations you could group together before you started getting more collisions than proper traffic. At the time, 17 workstations was considered the ideal maximum, above that number the percentage of collisions (and rebroadcast attempts) started to climb rapidly. One vendor that seemed prescient about this was 3Com. At first, they were pilloried for the design of their NICs because the hw didn't do any collision detection. Instead they relied on their sw driver to detect it. As long as there were relatively few collisions, this design was MUCH MUCH faster. But on a traditional hub-driven LAN the 3Com cards ended-up CAUSING more collisions since they didn't 'back off' as quickly.
Nowadays, every NIC vendor uses the 3Com-type model since switches have eliminated collisions. So the whole 17-workstation-max, avoid-bad-LAN-client-3Com-NICs advice is just so much ancient history.
I used to work for the University of Venice (Italy!) and their entire campus was setup as ONE big collision domain -- every building was tied directly together and everyone had trouble with lost connections... imagine :-) At the end of my stay there, I suggested to the IT Center that they install a switch at the central hub. At the time, this was considered an extravagance. I explained to them how I'd been going around to all their Novell servers, upgrading the LAN drivers to make them more resilient to ethernet traffic. I think they subsequently used my suggestion ("Our American consultant said...") to justify the expense and I'm sure it was well worth it. Now, of course, switches are The Standard and it's hard to find an old-style dumb hub, and consequently there's no cost premium for it. (P.S. I'm assuming my reader already knows the difference between a hub and a switch?)
Well, the final thought I had was about the problems we used to deal with on hubs. First of all, there was a lot of research into how many workstations you could group together before you started getting more collisions than proper traffic. At the time, 17 workstations was considered the ideal maximum, above that number the percentage of collisions (and rebroadcast attempts) started to climb rapidly. One vendor that seemed prescient about this was 3Com. At first, they were pilloried for the design of their NICs because the hw didn't do any collision detection. Instead they relied on their sw driver to detect it. As long as there were relatively few collisions, this design was MUCH MUCH faster. But on a traditional hub-driven LAN the 3Com cards ended-up CAUSING more collisions since they didn't 'back off' as quickly.
Nowadays, every NIC vendor uses the 3Com-type model since switches have eliminated collisions. So the whole 17-workstation-max, avoid-bad-LAN-client-3Com-NICs advice is just so much ancient history.
Monday, September 1, 2008
Is Rock music Male?
I had to work late the other night and I passed the time by blasting Boston's classic debut album at full-volume. When it was over I realized how much connection I'd felt to the music and the thought occurred to me that I'd been enjoying 'guy' music. But was there such a thing? Could any kind of popular music really be classified as male or female? There are plenty of great female rockers and most of my favorite singers are female. So it seemed silly to classify Rock by gender. Yet the feeling remained, that Rock Music was male. Could I justify that feeling? I could probably Google the idea and find a bunch of dissertations with long complicated explanations. But I'm sure I can write something comparable in an hour (or three) ...
First of all I had to figure-out what I meant by Rock Music. I've always heard that Rock was invented in the 50's with the introduction of "Black" musical themes to "White" pop music. But I've never felt any real connection to that early music. So I think it was more of a transitional style, as musicians experimented and slowly evolved a more 'pure' form of this new music. I may piss-off the piano players out there but I think a modern definition of Rock has to have the electric guitar. And more specifically the kind of anthem and power-chord driven music that was popularized in the late 60's and 70's, what is now considered Classic Rock. But I don't want to use a historical period as my definition! Instead I'm looking for some timeless quality to use in categorizing this 'male' music I'm pursuing.
Can I clarify my definition by considering which bands and songs I consider 'pure'? And does popularity factor into it? Certainly, Led Zeppelin was and is extremely popular. The aforementioned Boston was very popular, though it has since waned. But what about Heart, which is led by the Wilson sisters? Even though they're clearly considered Classic Rock I can't say that I've ever experienced that ethereal-level of connection with their music. So, again, the existing genre of Classic Rock isn't necessarily the definition of 'guy' music I'm searching.
What about grouping by musicians, especially singers? The singers that initially come to mind are hyper-masculine guys like Robert Plant or the singer from Boston. But I have no idea who Boston's singer is! Honestly, I've never had a strong connection to the actual singers. I mean, if I paid attention to lyrics I'd be a Country music fan, right? heh heh. And as much as I associate with the instrumentals I don't think the individual performances are what inspired my sense of connection.
Maybe I'm mistaking Music I Like for music that's male like me? I'm obviously going to connect most with the songs I like most, duh. But that seems like too simplistic and circular an argument. And the singers I actually like for their singing are usually women, like Aretha Franklin (who's R&B) or Tift Merritt (Country).
At last, I think I have a real clue. The music I'm considering Rock is music with a 'testosterone' edge to it -- aggressive, forceful, even sexual. This definition would make Rock 'male' but it wouldn't preclude women from enjoying or creating it since they have testosterone, too. I want to make clear that I don't mean the music has to be angry or violent, though. I don't think it's fair to blame that on testosterone. Again, there are probably doctoral dissertations that describe what constitutes Male, or what effect testosterone has on people, but for my purposes I just mean an energetic, impatient Joy For Life.
So now I have a working definition. Unfortunately it would then follow that Anything Teenage Boys Like is pure Rock, right? Maybe... Most of the stuff that kids listen to today is just noise to me. And a lot of it is 'urban' music with even more overt "Black" influence. Again, not stuff I've ever felt any connection to. My definition seems to be slipping away...
Ultimately, I think that it's not possible to say that Rock is male. Instead, I think that one of the elements of Classic music -- of any genre -- is that sense of testosterone. And that there are probably innumerable other elements that help make the Classics so classic. My favorite bands growing-up were XTC (not so manly) and The Police (manly, hence all the female fans). Rather than a 'male' sense of connection, both bands shared a cleverness, an understated sophistication in their arrangements and instrumentation. But now I really am going to leave it to PhDs to define these additional elements of great music!
First of all I had to figure-out what I meant by Rock Music. I've always heard that Rock was invented in the 50's with the introduction of "Black" musical themes to "White" pop music. But I've never felt any real connection to that early music. So I think it was more of a transitional style, as musicians experimented and slowly evolved a more 'pure' form of this new music. I may piss-off the piano players out there but I think a modern definition of Rock has to have the electric guitar. And more specifically the kind of anthem and power-chord driven music that was popularized in the late 60's and 70's, what is now considered Classic Rock. But I don't want to use a historical period as my definition! Instead I'm looking for some timeless quality to use in categorizing this 'male' music I'm pursuing.
Can I clarify my definition by considering which bands and songs I consider 'pure'? And does popularity factor into it? Certainly, Led Zeppelin was and is extremely popular. The aforementioned Boston was very popular, though it has since waned. But what about Heart, which is led by the Wilson sisters? Even though they're clearly considered Classic Rock I can't say that I've ever experienced that ethereal-level of connection with their music. So, again, the existing genre of Classic Rock isn't necessarily the definition of 'guy' music I'm searching.
What about grouping by musicians, especially singers? The singers that initially come to mind are hyper-masculine guys like Robert Plant or the singer from Boston. But I have no idea who Boston's singer is! Honestly, I've never had a strong connection to the actual singers. I mean, if I paid attention to lyrics I'd be a Country music fan, right? heh heh. And as much as I associate with the instrumentals I don't think the individual performances are what inspired my sense of connection.
Maybe I'm mistaking Music I Like for music that's male like me? I'm obviously going to connect most with the songs I like most, duh. But that seems like too simplistic and circular an argument. And the singers I actually like for their singing are usually women, like Aretha Franklin (who's R&B) or Tift Merritt (Country).
At last, I think I have a real clue. The music I'm considering Rock is music with a 'testosterone' edge to it -- aggressive, forceful, even sexual. This definition would make Rock 'male' but it wouldn't preclude women from enjoying or creating it since they have testosterone, too. I want to make clear that I don't mean the music has to be angry or violent, though. I don't think it's fair to blame that on testosterone. Again, there are probably doctoral dissertations that describe what constitutes Male, or what effect testosterone has on people, but for my purposes I just mean an energetic, impatient Joy For Life.
So now I have a working definition. Unfortunately it would then follow that Anything Teenage Boys Like is pure Rock, right? Maybe... Most of the stuff that kids listen to today is just noise to me. And a lot of it is 'urban' music with even more overt "Black" influence. Again, not stuff I've ever felt any connection to. My definition seems to be slipping away...
Ultimately, I think that it's not possible to say that Rock is male. Instead, I think that one of the elements of Classic music -- of any genre -- is that sense of testosterone. And that there are probably innumerable other elements that help make the Classics so classic. My favorite bands growing-up were XTC (not so manly) and The Police (manly, hence all the female fans). Rather than a 'male' sense of connection, both bands shared a cleverness, an understated sophistication in their arrangements and instrumentation. But now I really am going to leave it to PhDs to define these additional elements of great music!
Subscribe to:
Posts (Atom)
