IPv6 discussions

[xiaofan]

1. Singapore Consumer ISP Fibre Internet Plans and IPv6 summary

Updated on 27-March-2025. Please also refer to Post #3 about the details.
++++++++++++++++++++++++++++++

1) Singtel IPv6 related (mainly 6rd but also new on-going deployment of native IPv6 with /56 allocation)
https://forums.hardwarezone.com.sg/threads/no-more-ipv6-in-singtel-home-1g-fibre-broadband.6006714/
https://forums.hardwarezone.com.sg/...v6-6rd-before-any-experience-sharing.6915317/

Singtel's native IPv6 deployment seems still on-going. And it is very difficult for ONR users to get native IPv6 as it needs the help from backend network team and very few Singtel support people know how to do it.
https://forums.hardwarezone.com.sg/threads/singtel-5gbps-ipv6.7053976/

2) Starhub IPv6: /128 for WAN interface, routed /64 prefix for LAN interface.
Seems to have problem with pfSense
https://forums.hardwarezone.com.sg/threads/ipv6-on-starhub-1g-fiber-broadband.6835584/
https://forums.hardwarezone.com.sg/threads/ipv6-on-pfsense-wan-interface-starhub.6975288/

3) M1 IPv6: /128 for WAN interface, routed /64 prefix for LAN interface
https://forums.hardwarezone.com.sg/threads/ipv6-on-m1-broadband.6959543/

4) SIMBA IPv6: /128 for WAN interface, routed /60 prefix for LAN interface

5) VQ -- Static /64 for WAN, /56 for LAN, you need to request for it. Please refer to Post #3. If you have issues, ask in this thread or VQ thread.

Now they can allocate /56 prefixes via DHCP-PD also. no need static config liao.

6) No IPv6 for MR and WC.

+++++++++++++++++++++++++++++++++++++
2. IPv6 basic info: Youtube guide

 

[xiaofan]

This thread will be more for general discussion of IPv6 (using different routers, consumer routers, OpenWRT, pfSense, OPNsense, Ubiquiti, MikroTik, etc) and maybe not so much about specific problems with Singtel/M1/Starhub.

Edit to add: this will also serve as a consolidated info for IPv6 related information as mentioned by @Mach3.2.

 

[Mach3.2]

Fibre ISP IPv6 support matrix

ISP	IPv6 Support	Details/Notes
Singtel	6rd tunnel, limited rollout for DHCPv6 PD	6rd: /128 for WAN interface, routed /64 prefix for LAN interface DHCPv6 PD: /128 for WAN interface, routed /56 prefix for LAN interface 6rd tunnel config
Starhub	DHCPv6 PD	/128 for WAN interface, routed /64 prefix for LAN interface
M1	DHCPv6 PD	/128 for WAN interface, routed /64 prefix for LAN interface Supports DNS64/NAT64 DNS64 prefix: 2401:7400:8000:0:3:0::/96 2401:7400:8000:0:4:0::/96
MyRepublic	No	No lol
Viewqwest	Static IPv6	A routed /56 prefix assigned via DHCPv6 is available upon request from residential tech support at no additional charges. Not required to subscribe to static IPv4 add-on. Email residential tech support at: residential.support@viewqwest.com WAN: /64 LAN: routed /56 prefix for LAN interface If assigned static prefix is not routable, email residential tech support with mtr/traceroute to an address in your /56 allocation from external servers (i.e. Vultr looking glass servers).
Whizcomm	No	Assigned 2405:d180::/32 but no IPv6 prefixes announced under AS135600.
Simba	DHCPv6 PD	LAN: routed /60 prefix

Prefix delegation notes
/48: Great, follows best practices
/56: Acceptable, not great, but at least it still follows best practices
/64: Doesn't follow best practices. Only allows for a single LAN segment to be IPv6 enabled
Ref: https://www.ripe.net/publications/docs/ripe-690

Mobile ISP IPv6 support matrix

ISP	IPv6 Support	Details/Notes
Singtel	Yes*	End point receives a routed /64 prefix *Enabled on 5G standalone networks only. iOS carrier profile enables IPv6 by default (Checked on iPhone 13 iOS 17.5.1, carrier bundle 58.0) Post #17 by bert64
Starhub	Yes*	End point receives a routed /64 prefix *Enabled on 5G standalone networks only. Caveats: - On 5G SA network only. - iOS carrier profile only enables IPv4 by default (Checked on iPhone 13 iOS 17.5.1, carrier bundle 58.0). You'd need to enable IPv6 using a custom APN config profile. - On Android, you'd need to enable IPv6 in APN settings.
M1	Yes	End point receives a routed /64 prefix Supports DNS64/NAT64 Supported NVMO: Circles
Simba	Yes	End point receives a routed /64 prefix Caveats: - Unsolicited inbound traffic blocked - Enabling IPv6 support on iOS requires installing a custom configuration profile with cellular APN configurations

Information collated in this post is non-exhaustive, do comment in this thread if you have new information.

Last edited on 06 September 2025

 

[Mach3.2]

This thread will be more for general discussion of IPv6 (using different routers, consumer routers, OpenWRT, pfSense, OPNsense, Ubiquiti, MikroTik, etc) and maybe not so much about specific problems with Singtel/M1/Starhub.

Actually I'm thinking of throwing up a consolidated table of IPv6 support for easy reference, since the info are kinda all over the place..

 

[bert64]

ISP IPv6 support matrix

ISP	IPv6 Support	Details
Singtel	6rd tunnel, limited rollout for native dual stack via DHCPv6 PD	6rd: /128 for WAN interface, routed /64 prefix for LAN interface Native dual stack: /128 for WAN interface, routed /56 prefix for LAN interface
Starhub	native dual stack via DHCPv6 PD	/128 for WAN interface, routed /64 prefix for LAN interface
M1	native dual stack via DHCPv6 PD	/128 for WAN interface, routed /64 prefix for LAN interface
MyRepublic	No IPv6 support	-
Viewqwest	Used to support static IPv6 prefixes upon request but seem to have stopped doing so	-
Whizcomm	No IPv6 support	-

Technically whizcomms should have the same level of support as singtel - has anyone tried using the 6rd tunnel from a whizcomms line, or requesting a dhcpv6 prefix if in one of the limited rollout areas?

 

[Mach3.2]

Technically whizcomms should have the same level of support as singtel - has anyone tried using the 6rd tunnel from a whizcomms line, or requesting a dhcpv6 prefix if in one of the limited rollout areas?

I agree in theory it might work since they are on Singtel infrastructure, assuming singtel didn't segment the 6rd server from Whizcomms' customers, but I don't think there's any confirmations posted on this board so I'll just update that post as no support with caveat.

 

[xiaofan]

Singtel IPv6 specific info.

1. 6rd IPv6
1) /128 for WAN interface, routed /64 prefix for LAN interface
2) Singtel does not provide IPv6 configuration for Singtel ONR users. But you may be able to configure 6rd by yourself with the ONR.
3) For ONT users, you should be able to configure 6rd by yourself.

IPv6 Protocol: IPv6 - 6rd
6rd Runner Type: Manual.Configuratuon
IPv6 Prefix: 2400:d803::
IPv6 Prefix length: 32
Border Relay: 6rd.singnet.com.sg (202.166.127.6)
IPv4 Address Mask: 0

Or:

6RD Prefix: 2400:d803::/32
6RD Border relay: 202.166.127.6
6RD IPv4 Prefix length: 0

If you want to use SIngtel IPv6 DNS severs, you can use the following. But you can use other IPv6 DNS servers as well.

IPv6 DNS Server 1 : 2400:d800::1
IPv6 DNS Server 2 : 2400:d800::2

2. Native IPv6, deployment on-going from Nov 2023, still not fully deployed as of Nov 2024
1) /128 for WAN interface, routed /56 prefix for LAN interface

2) Singtel does not provide IPv6 configuration for Singtel ONR --> you have to request through Singtel and the backend team needs to enable native IPv6 for you -- you can not configure native IPv6 for the ONR by yourself.

3) For ONT users, you should be able to configure native IPv6 by yourself (DHCP-PD) on your router.

3. Example network configuration of Singtel 6rd for OpenWRT

root@OpenWrt:~# cat /etc/config/network

config interface 'loopback'
        option device 'lo'
        option proto 'static'
        option ipaddr '127.0.0.1'
        option netmask '255.0.0.0'

config globals 'globals'
        option ula_prefix 'dda5:edda:cf50::/48'

config device
        option name 'br-lan'
        option type 'bridge'
        list ports 'eth1'

config interface 'lan'
        option device 'br-lan'
        option proto 'static'
        option ipaddr '192.168.38.1'
        option netmask '255.255.255.0'
        option delegate '0'
        option ip6assign '64'
        list ip6class 'wan6'

config interface 'wan'
        option device 'eth0'
        option proto 'dhcp'

config interface 'wan6'
        option proto '6rd'
        option peeraddr '202.166.127.6'
        option ip6prefix '2400:d803::'
        option ip6prefixlen '32'

4. Example network configuration of Singtel native IPv6 for OpenWRT

root@OpenWrt:~# cat /etc/config/network

config interface 'loopback'
        option device 'lo'
        option proto 'static'
        option ipaddr '127.0.0.1'
        option netmask '255.0.0.0'

config globals 'globals'
        option ula_prefix 'fd5b:fdb2:a17d::/48'

config device
        option name 'br-lan'
        option type 'bridge'
        list ports 'eth0'

config interface 'lan'
        option device 'br-lan'
        option proto 'static'
        option ipaddr '192.168.18.1'
        option netmask '255.255.255.0'
        option ip6assign '64'
        list ip6class 'wan6'
        option ip6hint '0'

config interface 'wan'
        option device 'eth1'
        option proto 'dhcp'

config interface 'wan6'
        option proto 'dhcpv6'
        option device 'eth1'
        option reqaddress 'try'
        option reqprefix '56'
        option norelease '1'

 

[xiaofan]

M1 native IPv6 Specific Info:
1) /128 for WAN interface, routed /64 prefix for LAN interface
2) Not providing the IPv6 configuration for the bundled router. You need to set up by yourself
3) For pfSense, you need to use DUID-LL instead of the default DUID-LLT. You may need to carry out similar changes for other router systems.

Reference for Point 3: from the post by @bert64.
https://forums.hardwarezone.com.sg/...wan-interface-starhub.6975288/#post-150340553

 

[xiaofan]

Starhub native IPv6 Specific Info:
1) /128 for WAN interface, routed /64 prefix for LAN interface
2) By default enable IPv6 configuration for the bundled router (Linksys EA8100 onwards, Nokia Beacon 1, Nokia Beacon 2, Linksys Velop MX4200, Linksys Atlas MX2001)
3) It is said that pfSense is not working well with Starhub native IPv6 whereas MikroTik Router OS works fine. *

* Reference 3 from @firesong
https://forums.hardwarezone.com.sg/...ub-1g-fiber-broadband.6835584/#post-144793180

 

[xiaofan]

Mobile network info:

1) M1 -- IPv6 available
2) Singtel -- no IPv6 by default for 4G network. IPv6 available on request; 5G SA got IPv6. 5G NSA may or may not get IPv6.
3) Starhub -- no IPv6 for 4G network; 5G SA got IPv6.
4) SIMBA -- IPv6 available

 

[xiaofan]

1. SIMBA info: initially they do not support IPv6 but now it has native IPv6 for both 10Gbps plan and legacy 2.5Gbps plan. Take note SIMBA is using CGNAT.

2. VQ info: VQ starts to offer native IPv6 (Static IPv)6. Please refer to Post #3 for more info.

pfSense setup for VQ IPv6 from Mach3.2.

More about VQ IPv6 settings.

for those on the fence wrt to ipv6... just do it..

pro:
1) free. so why not make best use of it
2) NAT is no longer needed
3) huge update to the underlying internet connection
4) did I say free?

cons:
1) no perceived functionality or speed improvement if you have a static ipv4 currently
2) reading and background understanding needed before proceeding
3) no NAT. so if u screw up the firewall the risks are much higher

ViewQwest will provide you with
1) static wan ipv6 ip
2) static wan gateway ipv6 ip
3) public /56 ipv6 (which allows you to provision 256 /64 subnets) kudos to VQ for this.

Things to look out for
1) Firewall: icmpv6 is a critical component. So if you have been living in the drop all icmp ipv4 on wan world. you need a new strategy. everything else pretty much the same if you are using a zone based firewall.
2) DHCPv6 vs SLAAC. If you have android/chrome device, you will need SLAAC. DHCPv6 is not supported. My preference is DHCPv6 for the host running services. For the access devices, phone, laptop, tv, tablets SLAAC is the way to go. As usual read up to know what you are getting into.
3) test and verify!

As always, buy some beer and chips before you start. Cos you will need it.
Have fun!

 

[xiaofan]

I also believe what Mach3.2 mentioned here is also correct for Singtel. You can only request IPv6 prefix for once or twice (probably twice) within 24 hour time span.

https://forums.hardwarezone.com.sg/...ibre-broadband.6006714/page-13#post-150291980

Try enabling "Do not allow PD/Address release" (System > Advanced > Networking). I suspect it's like M1 where you can only request for a prefix once or twice within a 24 hour time span. Any more requests after that they will just ignore until 24 hours is up.

 

[xiaofan]

A common question asked is why need IPv6, you can search the posts from @bert64.

Example:
https://forums.hardwarezone.com.sg/...ibre-broadband.6006714/page-14#post-150307729

IPv6 is the production version of IP designed for a global network, IPv4 was an experimental protocol designed for the ARPANET and cannot properly support a global network, such that you need all kinds of complex workarounds (eg NAT and others) to keep it limping along. These workarounds add complexity, cost, performance bottlenecks and security risks.

Without IPv6, an increasing number of sites will be inaccessible to you and some things won't work, other things may still work but in a degraded fashion.

Several governments including China and the US have policies of moving completely to IPv6 and eliminating IPv4.

 

[xiaofan]

Consumer router IPv6 setting guide: (more to be updated)

Asus router
https://www.asus.com/sg/support/FAQ/113990/

TP-Link Deco:
https://www.tp-link.com/sg/support/faq/2642/

TP-Link Archer
https://www.tp-link.com/sg/support/faq/1525/

Netgear:
https://kb.netgear.com/24006/How-do-I-set-up-an-IPv6-Internet-connection-on-my-NETGEAR-router

 

[xiaofan]

More advanced router OS IPv6 settings: (more to be updated)

OpenWRT
https://openwrt.org/docs/guide-user/network/ipv6/start

pfSense
https://docs.netgate.com/pfsense/en/latest/network/ipv6/index.html

OPNsense
https://docs.opnsense.org/manual/ipv6.html

Ubiquiti Unifi
https://help.ui.com/hc/en-us/articl...eway-Static-IPv6-and-DHCPv6-Prefix-Delegation

MikroTik RouterOS
https://wiki.mikrotik.com/wiki/Manual:IPv6_Overview

Youtube Video Guide on basic IPv6 setup.

1) OpenWRT


2) OPNsense


3) MikroTik RouterOS


4) pfSense -- suprisingly no good video guide other than the following old video

 

[bert64]

Mobile network info:

1) M1 -- IPv6 available
2) Singtel -- no IPv6
3) Starhub -- no IPv6
4) SIMBA -- ?

When last i used Simba (during the free trial period), IPv6 was available on the Simba (TPG) mobile network, but with some caveats.

There was no official carrier bundle, so you had to configure the APN yourself.
On iOS you don't get the option for IPv6 unless you make a custom profile with the apple configurator tool, the default profile for "unsupported carrier" is stuck to just legacy networking.

They also blocked inbound traffic via IPv6.

Not sure if any of this has changed since the trial period.

M1 - IPv6 works on 4G/5G, but not on 3G which seems to use older equipment. IPv6-only mode with NAT64 also works, but is optional.
Enabled by default on iOS devices and many android devices.

Singtel - you can request IPv6 and they will enable it, doing so can be a troublesome process because their support staff are not trained on it. You have to enable it yourself on the handset (simple on android, involves creating a custom profile on iOS). Based on APNIC stats their IPv6 usage has gone up quite a bit so perhaps they are gradually starting to enable it more widely.

 

[hwzlite]

APNIC: IPv6 in the region (SG)​

• https://www.apnic.net/community/ipv6/ipv6-in-your-region/?cc=SG
• https://stats.labs.apnic.net/ipv6/SG

Capable: The percentage of users able to access online content using IPv6 in this Economy.
Preferred: ‘Dual stack’ (IPv4 and IPv6 enabled) systems that prefer to use IPv6 if given a choice.

More breakdown at "ASN" tab.

 

[xiaofan]

From the above link.

AS4773 == M1, Fibre and Mobile combined
AS4817 SIMBA -- more for Mobile now as the 2.5G Fibre Internet service just started
AS4657 -- maybe this is for Starhub Mobile??
AS3758 -- Maybe this is for Singtel Business Broadband??

ASN​	AS Name​	IPv6 Capable​	IPv6 Preferred​	Samples​
AS9506​	SINGTEL-FIBRE Singtel Fibre Broadband​	0.12%​	0.06%​	135434​
AS4773​	MOBILEONELTD-AS-AP MobileOne Ltd. MobileInternet Service Provider Singapore​	53.03%​	52.24%​	111581​
AS55430​	STARHUB-NGNBN Starhub Ltd​	61.52%​	61.02%​	93690​
AS45143​	SINGTELMOBILE-AS-AP SINGTEL MOBILE INTERNET SERVICE PROVIDER Singapore​	4.64%​	4.44%​	75069​
AS4657​	STARHUB-INTERNET StarHub Ltd​	0.69%​	0.65%​	36482​
AS4817​	STPL-SG-AP Simba Telecom Pte Ltd​	58.12%​	57.52%​	34510​
AS56300​	MYREPUBLIC-SG MyRepublic Ltd.​	0.06%​	0.04%​	23881​
AS3758​	SINGNET SingNet​	0.68%​	0.46%​	6343​
AS18106​	VIEWQWEST-SG-AP Viewqwest Pte Ltd​	0.14%​	0.04%​	5657​
AS135600​	WHIZCOMMS-AS-AP Whiz Communications Pte Ltd​	0.08%​	0.08%​	2457​

 

[Mach3.2]

Decided to email M1's senior management this time round regarding their policy of not delegating a prefix longer than /64 since it didn't get anywhere the last time I tried through IMDA.

Hopefully Singtel delegating /56 prefixes to consumers can pressure M1 into moving towards that direction.

Dear Mr Denis Seek,

I'm writing to propose a change in M1's prefix delegation policy to better align with industry best practices outlined in RIPE-690, Best Current Operational Practice for Operators: IPv6 prefix assignment for end-users - persistent vs non-persistent, and what size to choose.


It is recommended in RIPE-690 that ISPs delegate a /48 prefix to all customer premises equipment (CPE), and if some level of service distinction has to be made between consumer and business connections, a /48 prefix should be delegated for business customers and a /56 prefix to consumers.


Currently, M1 delegates a /64 prefix via DHCPv6 PD to CPEs, which contravenes industry best practices of delegating at least a /56 prefix. This also has the knock on effect of preventing customers from subnetting their local network, which can isolate other IPv4 only networks from IPv6 only sites.


While Singtel does not have high IPv6 penetration rate within their fibre broadband network due to the use of archaic 6rd tunnels which requires manual configuration by end users, there has been an observed limited rollout of native IPv6 support via DHCPv6 PD, which can be expected to be more widespread in the coming months. In contrast to M1, Singtel is delegating a /56 prefix to CPEs, which follows the best practices outlined in RIPE-690.


Thus, I implore M1 to review their prefix delegation policy to better align with industry best practices, or in the more pragmatic sense, to better compete with their competitors who are following IPv6 best practices.

Best regards,

 

[xiaofan]

Decided to email M1's senior management this time round regarding their policy of not delegating a prefix longer than /64 since it didn't get anywhere the last time I tried through IMDA.

Hopefully Singtel delegating /56 prefixes to consumers can pressure M1 into moving towards that direction.

Very well written.

Maybe some Starhub users can follow and send a similar letter to Starhub.