ros2的REP是啥？
参考
ROS 2 Target Platforms
REP Source
《软件工程：实践者的研究方法》
前言
ROS Enhancement Proposals (REPs)，是ROS组织对开发者的倡议，是一种规范。
是一种工程管理办法
记录
Support Tiers
Tiers即等级的概念，Tier1支持等级最高，Tier2次之，Tier3支持度最低。
但是这三个等级都是官方支持的，只是支持的细粒度不同
如以下是ROS2 C版本对各目标平台的支持力度，可以看到ubuntu 16.04处于Tier2的程度，说明开发者要获得最大开发支持，最好使用ubuntu 18.04。而ROS 通信中间件的支持，就是frtps支持最好，处在tier1的位置。
Crystal Clemmys (December 2018 - December 2019)
Targeted platforms:
| Architecture | Ubuntu Bionic (18.04) | MacOS Sierra (10.12) | Windows 10 (VS2017) | Ubuntu Xenial (16.04) | Debian Stretch (9) |
|---|---|---|---|---|---|
| amd64 | Tier 1 [d][a][s] | Tier 1 [a][s] | Tier 1 [a][s] | Tier 2 [s] | Tier 3 [s] |
| arm64 | Tier 1 [d][a][s] | Tier 2 [s] | Tier 3 [s] |
The following indicators show what delivery mechanisms are available for each platform.
" [d] " Debian packages will be provided for this platform for packages submitted to the rosdistro.
" [a] " Binary releases are provided as a single archive per platform containing all packages in the Crystal ROS 2 repos file [4].
" [s] " Compilation from source.
Middleware Implementation Support:
| Middleware Library | Middleware Provider | Support Level | Platforms | Architectures |
|---|---|---|---|---|
| rmw_fastrtps_cpp | eProsima Fast-RTPS | Tier 1 | All Platforms | All Architectures |
| rmw_connext_cpp | RTI Connext | Tier 1 | All Platforms except Debian | All Architectures except arm64 |
| rmw_opensplice_cpp | ADLink OpenSplice | Tier 2 | All Platforms except Debian | All Architectures |
| rmw_fastrtps_dynamic_cpp | eProsima Fast-RTPS | Tier 2 | All Platforms | All Architectures |
| rmw_connext_dynamic_cpp | RTI Connext | Tier 2 | All platforms except Debian | All architectures except arm64 |