Honest Cogent opinions without rhetoric.

alex at pilosoft.com alex at pilosoft.com
Wed Mar 8 06:56:00 UTC 2006

On Wed, 8 Mar 2006, Martin Hannigan wrote:

> >         I am looking for user experiences for people who have
> > purchased
> >transit from cogent in the 300Mbps or up range as far as performance,
> >stability, and any other measurable metric of quality you can come up
> >with.
> >
> >         We have heard a lot of negatives about them, about their
> >pricing model, about their network, about de-peering with Level 3, etc.
> >What we really need is actual information.
Much of the negatives is from jaded competitors who don't want to fairly
compete. Other than that, the answer is 'it depends'. 

At certain cities, your experience will be worse - Cogent doesn't have
peers with big boys in every city they are at - so you'll have more chance
of being backhauled to sfo/iad than if you bought from $bigger-carrier.

With regard to depeerings: they are a fact of life on the internet - and 
as a service provider, you should always have multiple transits, for this 
and other reasons. Yes, you obviously will have more risk of being caught 
in a depeering fight if you are buying from $low-price-leader-du-jour, 
because these are the ones more likely to be depeered by $big-boys for 
being "too-competitive". ;)

With regard to network stability: It *appears* (from number of recent 
fiber cuts) that Cogent doesn't have enough redundancy on intercity or 
metro transports - fairly recently network was cut in half for extended 
period of time due to two concurrent cuts. Not to say that doesn't happen 
to anyone else, happened to Sprint too, but, losing nyc->iad transport 
(and having everything go through ord) due to metro fiber cut in nyc 
is somewhat unexpected. 

With regard to peers: I can't say that cogent's peers are more congested
than any other carrier's peers. 

With regard to price: There are others who sell at about the same price. 
Cogent is far better than them. :)

Overall: Cogent can be a good part of a transit mix.

(from Marty)
>  From a global perspective[1], the top 12 (I stopped at Cogent since you
> are asking about them) service providers whose customers and peering
> partners reach the largest number of networks are listed below. You can
> make some fairly interesting assumptions on your own:

This gotta be the most meaningless metric ever. What does "reach"
mean?  More ASNs seen behind given network? What does it tell, precisely? 
There are ASNs which have significant chunks of intarweb (say, AS1668) 
behind them, while AS721 is not likely to matter in a grand scheme of 
things, even though all .mil installations are behind it.

Note that many Cogent customers, while using Cogent for outbound, prefer
not to announce any routes to Cogent for political reasons (or prepend or 
depref their routes). So, that metric won't be exactly helpful.

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