Getting two connections from different providers isn't necessarily just for physical redunancy, but will help you deal with routing problems inside networks. I have seen more T1s fail in their last mile than any mile in between. [Ala electrical interactions with copper, etc]. Just my opinion. -Deepak. On Sat, 12 Apr 1997, Allan Chong wrote:
Russ Haynal wrote:
This brings up another point I've pondered... I've noticed that many of the Backbone ISP backbone maps seem to have an amazing amount of similarity - i.e. connections between identicle sets of cities. I wonder how many different ISP's might be riding within the same Fiber bundle (the one right below some guy's back-hoe) If BBN and Internet MCI both run inside of MCI's fiber to/from a small ISP's hometown, then it won't make much sense for a small ISP to get a T-1 from MCI and BBN in the name of "redundancy" - If they both can be taken out with one backhoe. Might this risk still exist if my UUNET/Worldcom fiber also happens to lay 2 feet away from MCI's fiber in the ground in some kind of "telco right of way"
Often most of the major carriers will be using the same set of pipes across bridges and railway/highway overpasses. AT&T was advertising their "redundant path" network where they supposedly made some effort to avoid this. They were passing out maps and photos of spots with signs from all the major carriers.
Power, gas, etc. are often on those same bridges.
allan