Subnet support on N66 WAN port?

[SuperTeeJay]

Hello folks,

I will be having Hyperoptic broadband installed shortly and plan to use my N66 with Merlin instead of the supplied router. Their FAQ says:

"If you are a 20 Mb, or a 100Mb customer your router needs to support /31 (255.255.255.254) subnet mask on its WAN port in order for the router to work with Hyperoptic."

https://www.hyperoptic.com/connecting-a-non-hyperoptic-router/

(The ISP uses fibre to the building and then CAT6 from their equipment to a port in the flat.)

Could someone explain how I could configure the router to work properly? Thanks.

 

[joegreat]

I would say nothing to do here, just choose

under WAN "WAN Connection Type" = Automatic IP ​

and the DHCP of the provider will do the rest!

In case you get a fixed IP from the vendor you need to choose

under WAN "WAN Connection Type" = Static IP,
and enter the details as given from the provider under "WAN IP Setting" - including the Subnet Mask and Gateway​

I do not get why they question about "needs to support /31 (255.255.255.254) subnet mask on its WAN port" as this is default stuff for every router...

Maybe the right question is:
Does the router support manual setting of the WAN IP configuration (including Subnet Mask of 255.255.255.254, Fixed IP and Gateway)?

 

[ColinTaylor]

I do not get why they question about "needs to support /31 (255.255.255.254) subnet mask on its WAN port" as this is default stuff for every router...

Yes, initially I was a bit confused about this. But there is actually a difference .

They appear to be alluding to RFC 3021 (Using 31-Bit Prefixes on IPv4 Point-to-Point Links). Normally the smallest subnet you can have is /30 (255.255.255.252) because of the 2 reserved addresses (network address and broadcast address). RFC 3021 allows a /31 prefix by doing away with the two reserved addresses.

http://showipprotocols.blogspot.co.uk/2014/11/rfc3021-slash-31-subnets-for-ipv4-p2p-wan.html
https://www.ietf.org/rfc/rfc3021.txt

FYI My router's WAN connection is on a /22 (255.255.252.0) network.

 

[SuperTeeJay]

Thanks guys. It sounds like, initially, I should just plug it in and see if it works without messing with any settings.