Only one transit? For a reliable internet, two transits is the minimium
requirement, and you have but one, which is less then two, and two is what
you need... Curses...
You must immediately purchase some transit, which you need for internet,
for without transit you cannot have the internet that you so require.
I think the suggestion was to get multihomed to the same ISP. You can still
get redundant links to the same ISP and you won't be adding BGP entries on
the Core Routers. The benefit to this in a BGP world is that the ISP will
deal with which link to use, perhaps to different POPs. This only creates
entries in the internal routing. I agree, that having two seperate ISPs is
usually the best answer, but if ISPs were reliable enough perhaps two links
to the same ISP would be enough for some places.
Shel
I fail to see how this helps reliability in the case of ISP "routing
instability" I believe that last year one large ISP lost almost all of its
Bay Area connectivity and had a network meltdown due to "routing
instabilities" (whatever that means).
If you are running a mission critical network, I think you have no choice to
be multi-homed to at least two ISPS preferably not residing on the same
conduit that they both lease from the same transport network.
Bora
On Tue, Apr 03, 2001 at 08:13:59AM -0700, Bora Akyol had this to say:
I fail to see how this helps reliability in the case of ISP "routing
instability" I believe that last year one large ISP lost almost all of its
Bay Area connectivity and had a network meltdown due to "routing
instabilities" (whatever that means).
multi-homing may not help much if the ISPs you're connected to get their
connectivity from the same NSP and that NSP has issues (as you noted below)
...
If you are running a mission critical network, I think you have no choice to
be multi-homed to at least two ISPS preferably not residing on the same
conduit that they both lease from the same transport network.
as opposed to those of us multi-homing our mp3 file servers for maximum
reliability ... 
The problem is that currently ISPs are a lot less reliable than telcos or
hardware. You tend to get an upstream provider having a problem ( lasting
say a minute or more ) once every week or so while Telco or Hardware
problems will occur every year or so. One of the numbers is 50 times
bigger than the other.
As for using different pops it doesn't always work. We have 2 US pops
currently. One has 2 links to different pops of the same provider while
the other has 2 links to that provider and a backup link to another.
Last night the main providers entire California network when to hell for
about 2 hours. One pop was almostly completely offline while the other was
mostly working for the entire time.
With the currently level of reliability, redundancy of providers *is*
pretty much required.