I am collecting some info about ISP issued free routers for Fibre Internet here.
https://forums.hardwarezone.com.sg/threads/openwrt-router-firmware.5967482/page-18#post-149528916
1. As I have not used M1, I would like to get the help from the users here to confirm on M1 side. Thanks.
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Singtel issued free routers for Fibre Internet
2-wire 5012NV --> Pace A5520N --> Aztech DSL7003GRV(AC) --> Aztech DSL 7009GR(AC) --> Singtel AC Elite (AC1900) --> Singtel AC Plus (AC1200) --> SIngtel Mesh Router --> Airties Air 4960R -->Airties RT5703W (now)
Singtel ONR users may get mesh nodes like Singtel Mesh Extender and
Singtel AC Plus (AC1200) --> SIngtel Mesh Router --> Singtel Mesh Extender or Askey AP5100W WiFi Mesh (mesh node, not router) --> Singtel WI-FI 6 MESH AP5690W (not a router) or Airties RT5703W
Starhub issued free routers for Fibre Internet (D-Link models up to July 2017)
?? --> D-Link DIR-865L (2013-2014) --> D-Link DIR-850L --> D-Link DIR-868L and D-Link DIR-890L (for upgrade?) --> Linksys EA7500v2 --> Linksys EA8100 v1 --> Nokia Beacon 1 --> Nokia Beacon 2 (now)
M1 issued free routers for Fibre Internet (?)
RT-N15U --> RT-N56U --> RT-AC56S --> RT-AC68U (not free, for upgrade?) --> RT-AC1200G+ --> RT-AC2600 --> RT-AX55 or TP-Link Archer AX73 (short time) or Archer AX72 --> RT-AX3000P or TP-Link Archer AX72
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2. The older Asus routers from M1 are mostly supported by alternative FW except RT-AC1200G+, not the new ones though like RT-AX55 and RT-AX3000P (no Merlin support). TP-Link Archer AX72 and Archer AX73 are also unlikely to get alternative FW support.
For the older Asus routers which are no longer supported by Asus, you may choose to use the alternative FW and continue using them as a router or AP.
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Asus RT-N15, RT-AC56S (similar to RT-AC56U) and RT-AC68U are supported by
DD-WRT.
https://wiki.dd-wrt.com/wiki/index.php/Supported_Devices#Asus
Asus RT-N15, RT-AC56S (similar to RT-AC56u) and RT-AC68U are also supported by
FreshTomato.
https://wiki.freshtomato.org/doku.php/hardware_compatibility
RT-N15U is also supported by OpenWRT up to version 19.07.2 but not recommended.
https://openwrt.org/toh/asus/rt-n15
RT-N56U is supported by OpenWRT (but it is said 5GHz WiFi may have some stability issues)
https://openwrt.org/toh/asus/rt-n56u
RT-AC56S (similar to RT-AC56U) is also partially suppoted by OpenWRT without 5GHz wireless.
https://openwrt.org/toh/asus/rt-ac56u
RT-AC68U is a long life product and it is still supported by Asus official FW (latest FW: Version 3.0.0.4.386.51665, 98.78 MB, 2023/05/11) and Merlin alternative FW (386.12 stable version).
RT-AC68U is also partially supported by OpenWRT but no wireless (not even 2.4GHz).
https://openwrt.org/toh/asus/rt-ac68u
RT-AC1200G+ is not supported by alternative FW.
RT-AC2600 should be supported by OpenWRT (needs confirmation) by using RT-AC85P OpenWRT FW (with double RAM).
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