The report seermed to like the boxes from the companies that Alcatel bought. On this side of the pond they
did not get alot of traction.

>From my experience with a "large" Cisco network besides the normal too many fingers on the CLI to the router there were about one to
 two hardware failures a week on the big "C" devices. Most of these were interface cards but some were control cards on switches.

As long as you did not overrun the 12xxx series with too many BGP updates per unit of time they as a box were stable.

To calculate "99.99" per cent uptime you -

Define scheduled down time as any maintanance that can be done after giving the worldwide network at least five minutes notice of major
network outages ...

Define the device to be up as long as you can secure telnet into the box and get a command prompt -

Ignore BGP, routing or forwarding tables or any other routing issues because "Up-Time" means the box is up not that it is doing any usefull work ...

And finally go back to a "real person" deterministic protocol like "ATM" with PNNI and UNI so you
"know" when the network is down and do not have to guess ... My layer two network ran for two years with no hardware or routing issues ...

The other minor technical issue is that say you can calculate uptime on a "router" how do you calculate up time on the network? ... Since
just because one router is down the "network" is still up so individual up-time for a router in an IP network may only affect SLAs for customer
directly attached to it.

John (It Suites Dennis's Needs) Lee

David Barak wrote:
 
Okay, I'll bite...

the mentioned file,
http://www.nspllc.com/New%20Pages/Reliable%20IP%20Nodes.pdf
seems to be fluff to me.

There are many assumptions and statements about
reliability, but the methodology of how the numbers
were reached is not present.  If one assumes that one
has a router which fails very rarely, this would
dramatically affect network design.  However, this is
an assumption, not a conclusion.  The assumption of
the paper is that the Alcatel box has ultra-low
failure rates, while the Juniper and Cisco boxen have
relatively high failure rates.  Personally, before I
let something like this influence my buying/design 
decisions, I'd want to see some serious raw data...



=====
David Barak
-fully RFC 1925 compliant-

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