[130090] in North American Network Operators' Group
Re: Software-based Border Router
daemon@ATHENA.MIT.EDU (Michael DeMan)
Mon Sep 27 23:02:56 2010
From: Michael DeMan <nanog@deman.com>
In-Reply-To: <AANLkTim0O31VQopnykJmQY0hFagP+e7SzF6giRSmgOr4@mail.gmail.com>
Date: Mon, 27 Sep 2010 20:02:30 -0700
To: North American Network Operators Group <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
I have seen software based routers (FreeBSD+Quagga) in production at =
pennies on the dollar compared to Cisco for quite some years.
Up front, as other people have noted, you need to know what you are =
doing. There is no 'crying for help 24x7'. By the same token, if you =
know what you are doing then they can be a very cost effective =
solutions.
I have yet to see (or try out) MPLS and such, so if requirements need =
features like that, then probably open source may not be the solution.
The above said, other comments inline below...
On Sep 27, 2010, at 3:48 PM, Heath Jones wrote:
> Do jitter sensitive applications have problems at all running?
> What would you say is the point at which people should be looking for
> a hardware forwarding solution?
>=20
> Differences:
> - Hardware forwarding
Yes, absolutely, no hardware forwarding. This must be compensated for =
by utilizing as advanced/expensive 'commodity PC hardware' as possible. =
You want lots of CPU horsepower, fast busses (PCI-E x16 if possible) and =
good NICs so the OS can offload as much as possible to the hardware and =
not be bandwidth constrained. Even then, no way are you going to get =
anything close to what you can from a 'real' router. A classic trade =
off between technical needs & desires vs. financial constraints. =20
> - Interface options
Make sure there are least two NIC platforms. i.e., a pair of onboard =
dual gigabit plus another dual gigabit card. Bond the interfaces =
between the separate NIC platforms so one each gigabit link is off say =
the onboard and one off the NIC card. Utilize LACP.
> - Port density
Use VLANs - again, a quality NIC will help with this by offloading a =
good portion of the overhead to hardware.
> - Redundancy
Use a /29 to your eBGP provider and turn up two routers side-by-side. =
Again, if you are looking for hard core 'carrier grade' stuff, you =
should not be asking about open source. Pair the two routers, for eBGP =
sessions, and use a separate interface for them to talk to each other.
> - Power consumption
Always an issue, no way are you going to get pps from this kind of stuff =
like you would from Cisco.
> - Service Provider stuff - MPLS TE? VPLS? VRF??
Yup.
>=20
> Any others?
>=20
If somebody is on an extremely tight budget, is technically capable of =
doing utilizing open source to do what they need, and their requirements =
are limited enough that an open source platform would work for them, I =
would suggest they check into it. Ultimately, as always, it is buyer =
beware. Often with dedicated routers a support contract can cost as =
much as the router itself after a year or two, but sometimes companies =
need that support contract because they don't have the in-house skills =
already, etc. =20
I would never recommend either open source or dedicated hardware routers =
to anybody as a 'this is the only way to go' solution.
