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Haven't found info on max conn/max conn per second for ISR resp ISRG2

Hi all,

I've been searching for detailed numbers:

maximum connections for ZBF plus NAT-PAT (extended NAT entries)

Max connections per second ZBF plus NAT-PAT (extended NAT entries)

for different current platforms:

800 series

1800 series

1900 series

The data sheets don't state the numbers.

I appreciate any hint, where to find that info.




Bandwith is very moderate but the number of connections and connection rate is very high at peaks:

up to some 70,000 transactions within a short time, each transaction consisting of several short connections (I don't have the details yet but it could be up to 5 or 10 connections per transaction)

Hall of Fame Super Gold

Re: Haven't found info on max conn/max conn per second for ISR r

Cisco doesn't have or does not release this kind of performance number, so I'm afraid you will have to find by yourself.

Anyway the most importa factor remain the access spped, for example if you only have 10 Mbps, doesn't matter how manyn transaction per second, router will keep up.


Re: Haven't found info on max conn/max conn per second for ISR r

Very sad, that there are no numbers. A few years ago there were quite detailed infos available, e.g. how many bytes of RAM a CBAC-connection needs etc... so could at least give a *very rough* estimate if you know how much free mem you have, even if you calculate an insecurity of -50% to +100% you could at least have a rough estimate.

I do not agree on link speed as the primary issue. With short connections on a saturated 10 MBit/s line it could mean some 2000 or 1000 connections per second if you estimate a "short connection" at roughly 500 or 1000 bytes.

And with up to 2000 clients beeing active at the same time and each of the clients probably occupying several connections (maybe up to 10 or 20 because of connection/translation timeouts) you could end up with 20000 entries or more in the NAT and connection tables.

That seems to me a higher impact than a forwarding rate of 10 MBit/s

But thx anyhow and rgds,


Addendum: I have seen posts on message boards, reporting "cpu meltdown" on a 2811 with around 3000 conn/second and on a 1811 with around 1000 conn/second. That's why I was asking.

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