Nexu 7000: Difference in Control & Data Plane

[virgoboy009]

Hello Gents,

Can you please tell me what is the Difference in Nexu 7000: Control & Data Plane.

How do we can compare it with 6500 SUP engine.

I know Nexus 7000 control plane features  -

Forwarding table builts on control plane using routing protocols or static configuration.

OSPF,RIP,BGP,IS-IS & Eigrp are dynamic protocols.

But not able to find  Data Plane ( I/O module) Features ?

Can somebody tell me the answer for this .

Thanks and Regards,

KA.

[Oleksandr Nesterov]

Hi Karim

You're right all routing protocols are runing on control plane and routing decisions are made there.

On n7k main dataplane is supervisor.

Then information about this decisions goes down to data plane and programmed in hardware - on linecards.

If you need more info on i/o modules - you can check linecards parameters - fib,tcam, line rate etc..

For example:

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9402/ps9512/Data_Sheet_C78-437757.html

http://www.cisco.com/en/US/products/ps9402/products_data_sheets_list.html

HTH,

Alex

[virgoboy009]

Hello Oleksandr,

Can you please elaborate more on your comments for N7k Dataplane.

I understand that Dataplance does the following -

Data Plane ( I/O Module)

     Forwarding Information Base (FIB) and Cisco Express Forwarding (CEF) switching were introduced to make layer-3 switching deterministic. When IP routes are copied from RIB to FIB, their next hops are resolved, outgoing interfaces are computed and multiple entries are created when the next-hop resolution results in multiple paths to the same destination.

UFDM interface between URIB and IP FIB.

basically i want to know does each I/o module goes for a routing update ( controlplane)  as an examle from 10.1.200.X to 10.1.210.x . what type of cachign they does?

Can you also expalin more on  FIB TCAM and IP Prefixes

Thanks and Regards,

KA.

[Oleksandr Nesterov]

Hi KA

Forwarding Information Base (FIB) entries

128K

Number of entries that base can contain

FIB explanation:

http://en.wikipedia.org/wiki/Forwarding_information_base

For TCAM

type of memoty for storing ACL for example

http://www.cisco.com/en/US/products/hw/switches/ps708/products_white_paper09186a00800c9470.shtml#wp39459

So most of these characteristics are related to forwarding the traffic.

As for lookup - for example using when CEF - lookup will be done once for first packet and then programmed in fib.

So one packet will go to the control plane and all other will be kept in data plane.

But this is general version and each particular case will depend on particular config.

HTH,

Alex