I recommend you to take a look at DANOS.

https://danosproject.atlassian.net/wiki/spaces/DAN/pages/416153601/Carrier+Grade+NAT+CGNAT

- A very active open-source project.
- Sponsored by AT&T.

- Uses Vyatta (and DPDK for good performance)

- The Routing Engine is based on FRR.
- Syntax sounds like Junos.
- Is the ONLY ONE open source project(at least that I know) that implements CGNAT on Bulk Port Allocation mode(not deterministic/predefined).

- Had very good improvements on PCP recently.
- Supports a few NAT-ALGs.

I and some good friends here in Brazil had some good experiences with it.

Marcelo Gondin wrote this tutorial in pt_BR, mentioning about a case with:
26Gbps / 1.5Mpps / 11502 simultaneous clients / 192 used Públic IPv4 addresses.
https://wiki.brasilpeeringforum.org/w/CGNAT_Bulk_Port_Allocation_com_DPDK

Em sex., 19 de fev. de 2021 às 11:57, Steve Saner <ssaner@ideatek.com> escreveu:

We are starting to look at CGNAT solutions. The primary motivation at the moment is to extend current IPv4 resources, but IPv6 migration is also a factor.

We've been in touch with A10. Just wondering if there are some alternative vendors that anyone would recommend. We'd probably be looking at a solution to support 5k to 15k customers and bandwidth up to around 30-40 gig as a starting point. A solution that is as transparent to user experience as possible is a priority.

Thanks

--
Steve Saner
ideatek HUMAN AT OUR VERY FIBER
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