Catalyst 9200 Family (Throughput Capacity)

[Richard Pidcock]

General question for the community.  I'm looking to use a Catalyst 9200 as my internet access switch.  Considering bumping my service from 1Gbps to at least 2Gbps and possibly higher.  Can the 9200 switch support higher than Gigabit throughput capacity.  

Looking below is a snip from the 9200 series data sheet.  I see switching capacity at 128Gbps, but forwarding rate at 95.23Mpps.  It appears to me that if I have a 2Gbps internet connection I"m going to need something of higher capacity than the 9200 family can offer.  Welcome to some feedback from the community.

[Giuseppe Larosa]

Hello @Richard Pidcock ,

the problem is not the throughput but the features.

for internet access you will likely need NAT and a Cat9200 does not support it I suppose.

Hope to help

Giuseppe

[Richard Pidcock]

See attached topology. Any natting happens on my FW (i.e. not doing any natting on my router or switch).  So with that said, my concern is can a 9200 support more than 1Gbps of throughput.

[liviu.gheorghe · Accepted solution]

If all the traffic going through your switch would be composed of frames having the minimum frame length of 64 bytes, the forwarding rare of 95.23 Mpps would give you a throughput of around 6 Gbps. This is an extreme situation - Internet traffic is IMIX - different packet lengths - so your traffic going through the switch will be much more than 6 Gbps.

Hope this helps.

[Joseph W. Doherty]

BTW, believe you slipped a decimal.  For minimal sized Ethernet frames, I calculate about 64 Gbps.

[liviu.gheorghe]

Yes, you are right about slipping a decimal - I did the calculation in my head and it seemed right at that moment.

[Reza Sharifi]

Assuming the 9200 uses 2 10Gig interfaces for downlink and uplink, and considering the interfaces can perform at line rate, you have more than enough bandwidth for a 2 gig connection to your provider. A 1Gig interface should give you 760 Mbps of 64-byte packet; for a 10Gig interface, you should get over 7Gig.

HTH

[Joseph W. Doherty]

A 9200 has more than 2 Gbps capacity, a lot more capacity.  Also the PPS spec supports the full fabric bandwidth of 128 Gbps, i.e. wire-speed/line-rate even for minimum sized frames.