CISCO891 vs C891F - how much faster?

[Marc Luethi]

Hi everyone

My venerable 881 is choking on my recently upgraded VDSL Line, at around ~60Mpbs, when being used with ZBFW & NAT & 6RD. 

That's quite allright with me, as the DSL modem currently doesn't sync at more than 65/16 anyway, and after all, it's only a 881.
Still, I'd like to have a Cisco 8xx series router that will be able to cope with upcoming faster xDSL or cable lines - residential ISPs around here are pushing towards 250Mbps+ (DOCSIS), or even 1Gig (over fibre).

I borrowed a CISCO891 recently, and could bechmark it a little. All tests done with a single stream. Outside IF was the gig0, inside IF was the fast0&int.vlan1 combination, connected to a Catalyst 3750G-24T. Both sender and receiver connected to the same 3750G with 1Gbps. 

Disclaimer: I do know that my "testbed" will not be fully accurate, does not reflect real world scenarios etc. Yet, I am not rambling about "too slow" or anything. I know that the number I got are already beyond the levels that Cisco is/was marketing these routers for. I was hunting for ballpark figures. 

With smallish packet size (<100bytes) and no features at all, I was able to filled the 100Mbps link with.

87kpps  IPv4  (@ 60% CPU)
75kpps  IPv6  (@ 60% CPU)

Adding NAT (classic nat inside/outside, as NVI-NAT just kills the CPU), figures dropped to: 

 40kpps  IPv4 (@100% CPU),  100b packets
100Mbps  IPv4 (@ 70% CPU),  1500b packets  (didn't bother to record the pps figure here...)

Without NAT, but with ZBFW, the Numbers are pretty much the same:

 40kpps  IPv4 (@100% CPU),  100b packets
100Mbps  IPv4 (@ 70% CPU),  1500b packets  (didn't bother to record the pps figure here...)

But then with both ZBFW + NAT:

12kpps  IPv4 (@ 60% CPU),  100b packets
 80Mbps IPv4 (@100% CPU), 1500b packets  (still at ca. 12kpps)

Allright so far, it seems that the CISCO891 has a bit more juice than my CISCO881, but having a basic NAT+ZBFW config is already limiting it to <100Mbps. That's also quite allright, 80Mbps is way above the 15Mbps Cisco is claiming for routers of this class. 

Now, the more recent versions of the 800 Series (the ones with model numbers starting with C8xx instead of CISCO8xx) are said to be beefier. With the CPU probably being faster, I would expect the pps figures to increase.

But by how much?
How much increase can I expect with ca C891F or a C892FSP (even considering the C891-24X) over a CISCO891 or CISCO881?

If anyone knows about a white paper showing actual numbers ... please let me know.  I work at a Cisco Partner, myself, but so far, I've been unable to find any numbers, not even in PVT presentations or the likes.

thanks for sharing your thoughts, ideas or even test results.

Marc

[Joseph W. Doherty]

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

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In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

See attachment.

[Marc Luethi]

Thanks for sharing the link, Joseph. I know that document already.

I fear the answer iss missing the point somewhat: If the "copyright year" in the footer of the document is anything to go by, the information therein comes from a time when there were no C891F or C892FSP,  just Cisco891 or Cisco892.

About the latter I know what to expect - I played one of these, and got results that are not too far away from what the white paper suggests. 

It's the younger ones that I'm interested in.

Cheers

Marc

[Joseph W. Doherty]

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

Often, but not always, minor model series models have different features, but not a faster CPU.  I.e.  all 89x models might have the same basic performance.  Again, that's not always true.

I just did a quick search through the 89x series data sheets and FAQ, didn't find any mention of PPS.  Sometimes you can find this in published benchmarks (which I didn't search for).

You could also try contacting Cisco sales, and see if the have a PPS rating.