Cisco CAT 9200, does it support non-blocking and where can I find information? It's not mentioned in the data sheet.

[Rick de Goeij]

Cisco CAT 9200, does it support non-blocking and where can I find information? It's not mentioned in the data sheet.

[vb10]

Hello,

probably, you can use following resources

https://www.cisco.com/c/en/us/products/collateral/switches/catalyst-9200-series-switches/nb-06-cat9200-ser-data-sheet-cte-en.html

Table 8.            Bandwidth Specifications

It's not mentioned explicitly, but we can do some calculation, for example:

Description	Switching capacity	Forwarding rate
C9200-24T	128 Gbps	190.4 Mpps

C9200-24T has 24x1G ports and 4x10G uplinks. So, total bandwidth would be: 24*2G (1g for ingress + 1g for egress) + 4*20G = 128Gbps, which matches switching capacity from the table. 

[Rick de Goeij]

Thank you,

I understand this calculation, but non-blocking usually refers to the capacity available between the ports and the backplane.

For example, a set of 8* 1Gb ports should have 8* 1Gb (or 8* 2Gb for duplex) capacity to the backplane. Quite often this is not the case and this connectivity to the backplane is oversubscribed (e.g. 8 ports share 4 Gb connectivity to the backplane).

So the question is whether there is full capacity from the ports to the backplane.

[vb10 · Accepted solution]

Oversubscription to backplane is usually characteristic of modular switches with linecards and centralized forwarding (on sup), like cat4k, or Cat9400.

In fixed switches physical ports are reside and "served" directly by ASIC(s) on the switch. Of course, there are some intermediate components between physical ports and ASIC, but usually they don't have too much intelligence, and don't introduce "bottleneck".

So, main characteristic is ASIC performance. 9200 uses UADP 2.0 mini, which has up 100G total bandwidth.

https://community.cisco.com/t5/networking-blogs/uadp-the-powerhouse-of-catalyst-9000-family/ba-p/3764605

I would assume, that for example in switch 9200-24T, two of such ASICs are used - 1 to serve access ports, and 1 to serve uplink ports.  So, ideally architecture should be non-blocking.

If you need more details about architecture of the switch, I believe there are not too much places, where you can get it, apart of Cisco itself (TAC or account team)  :-)

[vb10]

Just to add, I'm talking about standalone switch. If stack is planned, then bandwidth/oversubscription should be calculated accordingly, taking into account  Stacking bandwidth limitation (160G), which probably might be exceeded under some circumstances (depends on model of stacking switches) 

[Rick de Goeij]

Thanks for you reply, it was helpfull. We can continue now.

Regards,

Rick de Goeij 

[apereira3]

Hello vb10,

I've the same doubt of this question.

Today, I have found the "Catalyst 9k e-book" that says Catalyst 9200 Switches Series have a single UADP 2.0 mini ASIC, in this case of non-mGig models (page 30).

The "Table Cisco UADP 2.0 , 2.0 XL and 2.0 mini comparison" on page 81 that talk about Cisco UADP 2.0 says that UADP 2.0 mini supports up to 80Gbps of inter-ASIC connectivity.

Please, you can access this document from the link below:

https://www.cisco.com/c/dam/en/us/products/collateral/switches/catalyst-9000/nb-06-cat9k-ebook-cte-en.pdf

So, is it documment authentic?

The Catalyst 9200 and Catalyst 9200L Series switches have a nonblocking architecture?

Thank you very much for your comment and explanation!

Allyson

[Leo Laohoo]

The Catalyst 9200 is meant to be the "cheapest" switch (among the 9K family).  Don't expect it to "compete" with the 9300 and this means that port buffers is the shallowest of the 9K range.