Transcript Choosing a Backbone Provider

Choosing a Backbone Provider
Avi Freedman
VP, Engineering
AboveNet Communications
What to look for
• Performance
– How fast are they when things aren’t broken?
• Reliability
– How much of the time are they broken?
– How badly do they break?
• Friendliness
– Will they speak BGP and work other issues?
– Clueful 24x7 Support
• Price
The Platonic Network
• Always up; zero packet loss to any
destination on the ‘net; instant response to
all technical questions, debugging issues,
route filter changes; $400-600/mbit on a
usage basis.
• No such provider exists.
What to Shoot for
• Always up, modulo 5-minute failovers a
max of once/month;
• Fastest class of connectivity;
• 15-minute support on urgent problems, via
phone if needed, and 2-4 hour turnaround
on all solvabe issues;
• $1000/mo/t1; $3000/mo for base frac T3;
down to $450/mbit in large quantity.
Performance
• There are two sides to backbone
performance – Internal backbone performance
– Peering
• Right now, independent verification of
performance is hard. Keynote and MIDS
suck.
• Soon, there will be other measures.
Performance (ctd)
• The ideal performance philosophy – Backbone: Run an uncongested network
everywhere, aiming for no more than 50% use
of the backbone links in normal circumstances,
to allow for bursting and allow flow to expands.
– Peering: Peer with everyone, everywhere, even
at one location, globally. Honor their MEDs,
and cold-potato traffic over your less congested
network. Put in private interconnects to any
provider you do > a few mbits/sec with.
Performance (ctd)
• Many backbones have diseased peering
policies, usually for political reasons,
sometimes out of cluelessness.
• So ask for their peering policy. The policy
itself is as instructive as the list of peers, but
you want to see that also (or get a lookingglass view).
• When asking for peers, ask for who is via
private interconnect.
Performance (ctd)
• Remember, Sprint, UUNET, CW are not the
net. Nor are any 9 providers. Just
connecting to the bigger providers can give
you OK connectivity, but wide uncongested
peering down into the 50% of the ‘net that
is the smaller networks is key.
Robustness
• Get into the internal architecture of the
network and customer-attach points with
sales engineers.
• There should be multiple fiber vendors,
multiple routers at every point, and they
should support cheap or free same-provider
multi-homing (ISDN, Frame, SMDS
backup). Ideally, different router vendors as
well, though that’s hard/more rare.
Robustness (ctd)
• Performance is harder to get answers on,
but existing customers of a given backbone
can give you a good measure of
robustness/downtime.
• The inet-access mailing list (send a message
with the body containing the word subscribe
to [email protected]) is a good
place to ask, as is around ISPF, ISPCON,
etc...
Robustness (ctd)
• The SLA (Service Level Agreement) is your
tool to get credits based on downtime, and
even, if things are really bad, the ability to
leave a term contract.
Friendliness
• You want IP space, as reasonable (you
WILL have to justify all space nowadays).
• You want them to speak BGP with you for
free; help you set up BGP; and make route
filter modifications within a few hours.
• In an emergency, you want them to get
someone senior on the phone.
Friendliness (ctd)
• You want them to limit ICMP to 128k/sec or
so to you from their network, to stop the
effect of smurf attacks.
• You need to be aware of whether the
provider uses the RBL (maps.vix.com/rbl)
and if you don’t want to be affected by it,
they need to be willing to help you route
around it.
Price
• $1000/mo for a T1 on a term price for a
good provider is a good rate (plus local
loop).
• $3000/mo for a 3mb/sec frac T3.
• $450/mb at t3 speeds, via T3 or ethernet.
So, Who?
•
•
•
•
Many regional providers
AboveNet (disclaimer, I work for them)
UUNET
Globalcenter
Regional vs. National Provider
• A regional provider can combine
connectivity to people with wide global
peering like AboveNet, and backup paths
(not too many) to enhance redundancy, and
access to other regional ISPs via peering
and customer relationships.
• Usually easier to find friendliness, and
being able to go beat on someone in person
can be handy.
Regional vs. National (ctd)
• Also, usually can negotiate cheap or free
ISDN, Frame, or SMDS backup via
redundant path.
• Downside: Concerns about business
stability over time.
Questions?
• Mail [email protected].
• Ask on the inet-access mailing list.