At 11:41 PM 8/19/96 -0400, Perry E. Metzger wrote:
Sean Doran writes:
| We can't pretend to be able to replace the phone networks until we can | achieve similar reliability. Phone networks typically are spec'ed to | two minutes a year downtime.
Uh huh, while I agree with you that the Internet is not remotely as stable as voice networks are, I think that this has a great deal to do with the revenue difference.
I strongly disagree. It has far more to do with the primitive engineering methods we are employing.
The mere fact that I've actually seen networks built in the real world that simply never go down and that don't cost an order of magnitude more leads me to believe that it can be done. I must admit that these networks are much smaller than the national networks a large provider tends to build -- on the order of twelve cities, fifteen or sixteen sites, and a hundred or two hundred ethernets. On the other hand, such a network is more than large enough that a "normal" network of this sort will experience substantial downtime in some of its links. The networks I've been involved with, though, go down orders of magnitude less frequently than you normally expect. Why is that?
1) redundancy in all components and links. 2) No "cowboy"ism.
3) These sites aren't turning up /hundreds/ of T-1's and other links on a given week. 4) Points of entry into these networks are very limited, and therefore the network manager has much more control over what comes into and out of his network as far as both data and routing advertisements. 5) These networks are not nearly large enough at this point in time to seriously push hardware to/beyond its design specifications. 6) Traffic patterns are relativelty predictable, you don't suddenly have triple the traffic over one link that you didn't have yesterday. Anyone care to add to the list? Justin Newton Internet Architect Erol's Internet Services
"Justin W. Newton" writes:
1) redundancy in all components and links. 2) No "cowboy"ism.
3) These sites aren't turning up /hundreds/ of T-1's and other links on a given week.
Ahem. How does that change the fact that router changes are frequently done "cowboy style"? How does that change the fact that one frequently calls a NOC and gets the comment "sorry, but *THE* router in Philly is down".
4) Points of entry into these networks are very limited, and therefore the network manager has much more control over what comes into and out of his network as far as both data and routing advertisements.
Again, this neither addresses the cowboy issue nor the lack of redundancy.
5) These networks are not nearly large enough at this point in time to seriously push hardware to/beyond its design specifications.
Again, this neither addresses the cowboy issue nor the lack of redundancy. The majority of the time my clients have outages caused by non-redundant hardware failures or cowboyism at providers, not by hardware being pushed too far.
6) Traffic patterns are relativelty predictable, you don't suddenly have triple the traffic over one link that you didn't have yesterday.
Again, this neither addresses the cowboy issue nor the lack of redundancy. I'm sure that all of what you mention are indeed problems -- problems that will lead to missed install dates, slow networks, etc. None of those, however, are the problems that I'm talking about. Perry
participants (2)
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Justin W. Newton
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Perry E. Metzger