Route Processor (RP) VS CPU

[Raoof]

is there any difference between the two terms? and speaking about the old 1st,2nd ISR ex (2800,2900), are the CPU and RP physically seperated ? or it is all about seperated functions where the RP is where the routing processes take place ? 

Thank you 

[Jon Marshall · Accepted solution]

Generally speaking you see RP being used in hardware devices where the RP is responsible for the control plane functions such as establishing routing peerings and building forwarding tables etc. and then there are dedicated hardware chips that are responsible for the actual forwarding of the data using the forwarding tables built by the RP. 

For the ISRs you are referring to as far as I know they do not have a RP as such just a general CPU that does both functions ie. the RP and SP but crucially there are no dedicated hardware chips in those devices. 

Jon

[Raoof]

@Jon Marshall , thank you 
so in the platforms that use the RPs, we will find the CPU or ASICs and the RPs
it is a little bit confusing as long as the new ISR series as an example ISR 1000 mention to the processors by ASIC

[Jon Marshall]

I am not familiar with the ISR 1000 series but a quick look suggests it is using multiple cores some of which are dedicated to the control plane (RP functionality) and some to the data or forwarding plane. 

Of course that could mean that it is still just a main CPU using cores as opposed to an RP/SP (Switch Processor) where the SP part is using dedicated ASICs and are not part of the main CPU. 

Jon

[Raoof]

@Jon Marshall  thank you again