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Old June 8, 2012, 01:26 PM
zsayeed zsayeed is offline
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Join Date: April 19, 2007
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Quote:
Originally Posted by Zunaid
US is the internet. It's not like there is only one cable feeding everyone in the US. There are multiple redundancies over redundancies. You cut one, ten will rear it's head. Bad planning and incompetency in Bangladesh is why we still have one real connection to the rest of the world.
Not quite, For Network planning purposes, we ususally render 9 is to 10 redundancy here in USA. That is for 9 links we have one redundancy. This usually goes for HLR-STP connection planning - which is the heart of the Wireless Infrastructure. For SDH-SONET we do the same. If less than 9 active links we do n+1 redundancy planning. The OSPF/IP Rerouting protocols should take care of the Layer2-3 rerouting. For disasters, we dispatch a team to bring about the network back on line. Our 5ESS switches were 99.9999% reliable. Even they had 1+1 redundancy planning. Our Verizon Network's 5ESS switch was still active on battery power during the 9-11 crisis. The switch was at the WTC Basement. For the Katrina Hurricane the Company created ad-hoc umbrella cells on fly-by helicopter. Usually the Core infrastructure is done by WDM (Wavelength Division Multiplexing) optical lines, with redundancy. The federation of carriers would kick in for disaster recovery, that is if ATT Core is okay and VZ core is not, then they would share the link for nation-wide coverage. Before trivestiture, ATT owned submarine cable division ships usually docked at Baltimore. You could see them before and after you entered the tunnel. Then they were bought by Tyco.

For some reason Sharks would like to chew those cables, perhaps they were annoyed or attracted by the frequencies in those cables. So the ships did have to be dispatched, and there were ripped cables found.
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Last edited by zsayeed; June 8, 2012 at 03:57 PM..
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