Re: [Coin] mtpsa and P4

[Radostin Stoyanov <[e-mail]>]

Hello Hemant,

Thank you for your feedback.

In addition to VMs, cloud providers also provide fully managed container 
orchestration services (Docker, Kubernetes) and serverless computing 
(lambda functions). In contrast to VMs, these technologies have higher 
density, low start-up times (milliseconds or seconds), and automated 
lifecycle management, scaling, and orchestration. A single node in a 
cluster could run workloads from many customers and using a separate 
virtual switch instance for each customer could have a significant 
overhead. Cloud providers often use SmartNICs (AWS Nitro, Azure 
SmartNICs) to offload packet processing to specialised hardware.

MTPSA aims to address the problem of programmable data plane (PDP) 
virtualization [1] as opposed to providing multiple isolated logical 
networks [2]. It is still an early work and it was presented on December 
1, 2020 at the 3rd P4 Workshop in Europe (EuroP4). We proposed an 
implementation of a P4C compiler backend [3], BMV2 software switch 
target [4] and a P4-NetFPGA prototype [5].

[1] https://ieeexplore.ieee.org/abstract/document/9078127
[2] 
https://www.gta.ufrj.br/ensino/cpe717-2011/openflow-tr-2009-1-flowvisor.pdf
[3] https://github.com/mtpsa/p4c
[4] https://github.com/mtpsa/behavioral-model
[5] https://github.com/mtpsa/P4-NetFPGA-MTPSA

I hope this helps.

Best wishes,
Radostin

On 09/02/2021 16:24, hemant=[e-mail] wrote:
>
> For a host, such as a user using a cloud, the cloud operator just 
> provides a VM per user or multiple VMs to a user.  This is why, for a 
> host, a MTPSA wasn’t necessary.  With a network virtual switch, of 
> course, MTPSA would help.  However, in the same cloud, if a virtual 
> switch is used, why not just provide a virtual switch per user and the 
> switch uses a few ports? This way MTPSA is avoided.  Use a router to 
> isolate virtual switch traffic.  If I really want to separate user 
> traffic, I could also use a virtual router per user and don’t use 
> MTPSA – of course, a router has multiple interfaces to supports 
> connections to different VMs for a user.
>
> Around May 2017, the first P4 compiler (p4c) came out as p4lang/p4c.  
> Hardware asic vendors have taken this p4c and developed their p4c 
> backends.  It takes few years to develop a compiler backend.  I 
> suspect, this is why P4’s focus could not get to MTPSA.  In the past 
> few months, a P4 to DPDK p4c backend was added to p4lang/p4c.   Now 
> that server machines are running P4 to DPDK, I think, more virtual 
> switch R&D will take place. In the past there has been a P4 to OVS 
> (Open Virtual Switch) but I don’t know if this effort looked into MTPSA.
>
> Also, the source code for the P4 bmv2 software switch is obtuse and 
> hard to change causing more delays.
>
> Best wishes,
>
> Hemant
>
>