Channelized DS3 with Linux?

minion asks: "We've been struggling to find a channelized DS3 card for Linux that is a standard PCI format (not CompactPCI, mPCI, etc). I find it hard to believe others out there don't want the same, as a lot of ISPs could save a lot of money this way, since Cisco routers that handle channelized DS3 *start* at $30,000! I've found this card, but that is all that I've found. It would be great to dump our current Cisco, and use it as a spare if our Linux router fails. Does anyone else have some experience with this?"

Comments

What does this card run anyway

[MerlynEmrys67]

So you never specify how much this DS-3 card runs you. I can't see volumes being that high, so I am assuming it is a multi-hundred dollar card (and not breaking into the thousands). That said - are you planning on a reliable Linux Router (multi power supplies, redundant yada yada yada's) or just a low end box with a couple of these cards thrown in.

If you are talking about the former - you might be suprised to find out you won't be much under 30K (those reliability things are expensive), if not - how much are you willing to give up in reliability (6 9s w/ Cisco - 3 9s with Linux + cheap hardware) and what is the cost of the downtime.

If you all ready have the Cisco kit (you did say you would run it for redundancy) - why change a working configuration for Linux ? Is it because "Linux is cool" or is there a business reason. If it is the former - I doubt you will be successful. If it is the later do the analisis above and see what the answer really is

Random thoughts...

[FreeLinux]

The thought of relying on a standard PC to drive/frame/time/switch a DS3 makes me nervous. There is a lot to be said for Application Specific Integrated Circuits(ASICs), which is what the Cisco uses.

Cisco's routers are expensive. Perhaps Nortel, Juniper, Foundry, Fore, Riverstone, etc might be less expensive but offer similar functionality and reliability.

How many channels are actually needed from the DS3? A Cisco 3600 can drive up to 12Mbps on a HSSI interface and would cost a lot less the $30,000 but, you couldn't go beyond 12 Mbps.

How much does a DS3 cost you? In my area, the monthly cost of such a circuit is such that a one time cost of $30,000 for hardware is really no big deal.

WHY?

[lostindenver]

as my grand pappy said: Use the right tool for the right job... You could use juniper or nortel. But just do it right.

Maybe?

[FreeLinux]

PCI Adapter

PCI Adapter

Linux Router Page

PCI Bus Speeds

[FreeLinux]

33Mhz X 32 bit PCI = 1 Gigabit
66Mhz X 32 bit PCI = 2 Gigabit
66Mhz X 64 bit PCI = 4 Gigabit

Actual throughput for each of these bus types is a bit less than the theoretical values above. However, having multiple 54Mbps cards on a single 33Mhz PCI bus should not be a problem from a bandwidth perspective.

Re:PCI Bus Speed Limitations?

[DetrimentalFiend]

If the PCI bus couldn't handle 54Mbps, then why would people have 100bT cards much less gigabit (and 10 gigabit on the way)?

There's a REASON Cisco line cards are expensive

[pyite]

It's not as if Cisco has no competition and can charge whatever they want. The reason Cisco chassis and line cards are so expensive is because they are GOOD and FAST. For example, the Catalyst 6500 has a 32Gbps backplane and with a SFM, a 256Gbps Switch Fabric. Fast WAN connections are generally only used on networks with large LANs and such organizations can justify something like a 6513, which loaded with a few cards, clocks in around $125,000.