The wap121, 321, 551 and 561 do support radius accounting. I don't know what price point you were looking for, but which model you choose depends on how many users and the capabilities you are looking for.
Enable RADIUS Accounting—Enables tracking and measuring of the resources a particular user has consumed, such as system time, amount of data transmitted and received, and so on. If you enable RADIUS accounting, it is enabled for the primary RADIUS server and all backup servers.
I am not sure of the details, or format of the accounting info.
Hello, This article will describe how to configure PPTP VPN on the new
RV340/345 routers from the Small Business series. RV340/345
Configuration The first step is to enable the PPTP Server: Go to VPN ->
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Article ID:5748 Use TheGreenBow VPN Client to Connect with RV34x Series
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Article ID:5728 Configure a Teleworker VPN Client on the RV34x Series
Router Objective The Teleworker VPN Client feature minimizes the
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