RISC OS Developments have been open about working on a new modern TCP/IP stack (funded by a commercial user) over the last 18 months for RISC OS 5. We are really excited that this has now resulted in a release for the general RISC OS Community!

This is release 1.0 (as with any first release they want lots of feedback, but don't immediately put on all your critical production systems).
 
It is based on the BSD stack but a major aim has been to make it as compatible and easy to fit into RISC OS as possible. It should also be easier to update with new versions and track the BSD stack. And there is even documentation!
 
There is a lot to digest here so we will run some in-depth future articles, but it is very exciting!
 
RISC OS Developments lists the key features as:- 

Modern TCP/IP stack supporting IPv4 and IPv6 network/internet standards

Static (manual) and automatic address assignment via DHCP (IPv4 and SLAAC (IPv6)

Easy installation (or uninstall) alongside the classic RISC OS network stack. No need to replace your OS - it can be installed on any modern-ish version of RISC OS 5 (ideally 5.24+), but please check the supported platforms below.

Supports Acorn's internet 4 (80s/90s) and 5 (~1996 onwards) APIs for compatibility with every network application we have found to test with.

Highly compatible - even your existing network config files work seamlessly with the new stack!

No requirements for developers to modify existing code (unless they wish to).

New Open Source Resolver and MBufManager modules to replace closed-source versions. These are compatible with the older stack too, to allow developers to test new software (eg. IPv4 and IPv6 aware applications) on all machines.

Extensive documentation included for developers with no restrictions on access.

Dynamic network configuration means no more reboots when reconfiguring your networking (at last!)

802.11 protocol support paves the way for wifi

Unlocks potential for higher performance networking - stack supports much larger mbufs, jumbo frames and more. Real world performance varies based on application, typically ranging plus/minus 25%, but can be dramatically faster. For example, Titanium users report up to 40x faster performance at gigabit speeds! Note that this is with existing, unmodified software.

Supports larger number of sockets (although existing applications will be limited to Acorn's previous specifications to avoid compatibility issues).

For the first time, Unix Domain Sockets are supported to allow inter-task communication in line with other platforms.

Optimized for ARMv7+ platforms, but also supports ARMv5 such as Pi zero and Pi 1.

Testers report noticeable network reliability improvements with the new stack. To quote one user "I've not been able to do that for a number of years... Well done to the TCP/IP stack developers - it's made RISC OS more producive."

Open Source technology coupled with commercial partnerships mean that the new stack (and its source code) is available to all RISC OS users, developers and vendors equally, at no cost.

Responsive feedback system allows both users and developers direct access to information, resources and assistance from ROD and its developers.

 
The next step will be to expand things with more drivers and support, improved network configuration, and of course... wifi
 
You can download ad try the software for yourself from the RISC OS Developments website