Greener grass on the other side of the fence
As an aside, it always amazes me that the Internet even works (particularly for an infrastructure that the unwashed masses seems to think will replace the existing telephone network), but I guess the same could be said of any chaotic (in the non-linear sense) system...
I'm not sure the telephone network is really that robust. Think about the SS7 network and a world with 50,000 CLEC's. Like most things, you don't want to really know what's in the sausage. Some systems are designed with a high degree of control, so everything works correctly. But they often have the property of catastrophic failure when any part fails to work perfectly, such as the cascading failures of the western power grid last year. Central, hierarchial control is alluring. But there are still trade-offs. It used to take a week (or more) to add/change/update network routes in the prdb (and its predecessors). Perhaps acceptable when the central control was working, but it also took that long to fix things when the central database was screwed up. If you were really lucky, you might be able to convince someone to do an 'emergency' change in a day or two. We (myself included) often express amazament how the network manages to continue functioning. However, the system might not be as out-of-control as some people think. It is definitely chaotic. On the other hand, it has shown itself remarkably resiliant to the many evil things people and nature have done. I'll note I'm writing this note while watching white scan lines roll over my highly reliable TCI cable service, NOT! -- Sean Donelan, Data Research Associates, Inc, St. Louis, MO Affiliation given for identification not representation
I'm not sure the telephone network is really that robust. Think about the SS7 network and a world with 50,000 CLEC's. Like most things, you don't want to really know what's in the sausage. Some systems are designed with a high degree of control, so everything works correctly. But they often have the property of catastrophic failure when any part fails to work perfectly, such as the cascading failures of the western power grid last year.
Years ago, it WAS that robust. Virtually not central control. The switches were internally redundant [axe off part of a #1 crossbar switch; like a worm the rest keeps wiggling...], trunking was almost too simple to break in increments greater than one, etc. But we've traded dumb redundancy for speed and efficiency. And we've paid for that. It struck me that the Martin Luther King Day ATT voice crash [?1991?] was chillingly parallel to this year's frame outage -- both went down on DoS from Sorcerer's Apprentice worth of maintenance messages. -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close........[v].(301) 56-LINUX Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433
I've worked in technical management at both MCI and Pacific Bell. Take my word for it, DAIL-TONE is a miracle, a miracle that it's there. At 05:40 AM 6/29/98 -0500, Sean Donelan wrote:
As an aside, it always amazes me that the Internet even works (particularly for an infrastructure that the unwashed masses seems to think will replace the existing telephone network), but I guess the same could be said of any chaotic (in the non-linear sense) system...
I'm not sure the telephone network is really that robust. Think about the SS7 network and a world with 50,000 CLEC's. Like most things, you don't want to really know what's in the sausage. Some systems are designed with a high degree of control, so everything works correctly. But they often have the property of catastrophic failure when any part fails to work perfectly, such as the cascading failures of the western power grid last year.
Central, hierarchial control is alluring. But there are still trade-offs. It used to take a week (or more) to add/change/update network routes in the prdb (and its predecessors). Perhaps acceptable when the central control was working, but it also took that long to fix things when the central database was screwed up. If you were really lucky, you might be able to convince someone to do an 'emergency' change in a day or two.
We (myself included) often express amazament how the network manages to continue functioning. However, the system might not be as out-of-control as some people think. It is definitely chaotic. On the other hand, it has shown itself remarkably resiliant to the many evil things people and nature have done.
I'll note I'm writing this note while watching white scan lines roll over my highly reliable TCI cable service, NOT! -- Sean Donelan, Data Research Associates, Inc, St. Louis, MO Affiliation given for identification not representation
___________________________________________________ Roeland M.J. Meyer, ISOC (InterNIC RM993) e-mail: <mailto:rmeyer@mhsc.com>rmeyer@mhsc.com Internet phone: hawk.mhsc.com Personal web pages: <http://www.mhsc.com/~rmeyer>www.mhsc.com/~rmeyer Company web-site: <http://www.mhsc.com/>www.mhsc.com/ ___________________________________________ SecureMail from MHSC.NET is coming soon!
participants (3)
-
David Lesher -
Roeland M.J. Meyer -
Sean Donelan