NPE-G2 vs. Sup720-3BXL

David Storandt dstorandt at
Fri May 15 12:23:08 CDT 2009

I would love to use the RSP720-3CXL, but cost and the PA OC3 are the

If the RSP720s will run in a 6500 chassis, great! We wouldn't have to
purchase new chassis and the increased downtime for the swap-out.

RSP720 don't support the older bus-only FlexWAN either with the OC3 PA
we're using, so we'd have to figure out a solution for that - SIPs,
Enhanced FlexWAN, or external routers. Bah.

...the RSP720s + chassis + OC3 solution more than double our $20k/node
budget, so that's a much tougher sell internally.


2009/5/15 Alex H. Ryu <r.hyunseog at>:
> Cisco 7304 may not adequate for service provider.
> It's CPU/IO-controller is tied together, and doesn't provide much of
> benefit.
> Cisco 7200/7300 is enterprise solution pretty much, and doesn't support
> distributed CEF.
> If you are considering SUP720-3BXL, why not considering RSP720-3CXL ?
> Alex
> Aaron Millisor wrote:
>> We ran into a similar quandary and have about the same amount of
>> traffic as your network. When purchasing gear a year ago we decided
>> against 7200's with an NPE-G2 as insufficient for the load. Have you
>> looked at the 7304?
>> The Cisco 7304 with an NSE-150 processing engine on it offloads a lot
>> of the packet processing to dedicated hardware, and doesn't have TCAM
>> limitations for routes. You can hold several full feeds and do the
>> amount of traffic you're talking about without breaking a sweat.
>> It is capable of supporting both legacy port adapters (from your
>> Flexwan or 7200 routers) and SPA cards with the right add-in modules,
>> which IIRC is only a few hundred dollars.
>> I'd be glad to answer any questions you have about our implementation.
>> --am
>> David Storandt wrote:
>>> We're stuck in an engineering pickle, so some experience from this
>>> crew would be useful in tie-breaking...
>>> We operate a business-grade FTTx ISP with ~75 customers and 800Mbps of
>>> Internet traffic, currently using 6509/Sup2s for core routing and port
>>> aggregation. The MSFC2s are under stress from 3x full route feeds,
>>> pared down to 85% to fit the TCAM tables. One system has a FlexWAN
>>> with an OC3 card and it's crushing the CPU on the MSFC2. System tuning
>>> (stable IOS and esp. disabling SPD) helped a lot but still doesn't
>>> have the power to pull through. Hardware upgrades are needed...
>>> We need true full routes and more CPU horsepower for crunching BGP
>>> (+12 smaller peers + ISIS). OC3 interfaces are going to be mandatory,
>>> one each at two locations. Oh yeah, we're still a larger startup
>>> without endless pockets. Power, rack space, and SmartNet are not
>>> concerns at any location (on-site cold spares). We may need an
>>> upstream OC12 in the future but that's a ways out and not a concern
>>> here.
>>> Our engineering team has settled on three $20k/node options:
>>> - Sup720-3BXLs with PS and fan upgrades
>>> - Sup2s as switches + ISIS + statics and no BGP, push BGP edge routing
>>> off to NPE-G2s across a 2-3Gbps port-channel
>>> - Sup2s as switches + ISIS + statics and no BGP, push BGP edge routing
>>> off to a 12008 with E3 engines across a 2-3Gbps port-channel.
>>> Ideas and constructive opinions welcome, especially software and
>>> stability-related.
>>> Many thanks,
>>> -Dave

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