From: Dave McGuire <mcguire@neurotica.com>
If you need to route something like a T1 or T3 line, that's pretty tough to do on anything but a purpose-built router due to support for those types of hardware interfaces.
That's not really true, except for very exotic or very ancient interfaces. I have at various times had DDS/ISDN, T-1/CT-1, T-3/DS-3, HSSI as well as Ethernet, TR, FDDI and ATM up to OC12 running on x86 platforms under various open source OSes (usually FreeBSD or OpenBSD) in production. Admittedly, FDDI, TR & ATM support have aged poorly in OSS, I haven't tried HSSI in years, and not too many people are provisioning DS-3s or OC-12 these days given the alternatives. What you don't get on the open source platform relative to a Cisco, et. al., is the protocol support. Pretty much only IP and limited higher level serial protocols (SDLC/HDLC/PPP/SLIP).
Further, for more modern circuits like OC192s, etc, there really aren't too many general-purpose computers available that can move data that fast in any predictable or consistent way,
While I'm unaware of an OC192 card for, say, PCI-e, FreeBSD on modern systems using Intel or Chelsio PCI-e ethernet cards can reliably route between 10G ports at wirespeed. I haven't gotten any of the Chelsio 40G cards yet, but they're supported as well. There are lots of folks doing exactly this to avoid the cost of something like a Cisco 12000 series router. Not just in labs or moms basement; for example the NANOG mailing list regularly has folks talking about this sort of setup running with BGP as core infrastructure. Folks like ServU have built a business around Intel ecosystem + BSD + 1/10/40G routers. What you definitely don't get on OSS is more than rudimentary QoS. Sophisticated bandwidth management pretty much requires dedicated ASICs.
and nothing anywhere near as reliable or internally redundant as something like a big Cisco or Juniper machine. They exist with their six-figure price tags for a reason.
I would agree with this. From: systems_glitch <systems.glitch@gmail.com>
V.35 sync serial. You can *get* V.35 cards for PCs, but I'd imagine it's not supported in most OSes I'd want to do routing in (namely, OpenBSD).
You'd be surprised. The Lan Media Corp sync serial cards are pretty well supported on OpenBSD. The Sangoma sync cards might be; the T-1 cards are. KJ