IPv4 1 or 8 Static IPs vs. IPv6

Quick questions about access to a home network from the internet.
I know when I signed up to Zen I was offered 1 or 8 static IP addresses free. I choose 1 at the time. I did not need 8 (then) and there was / is shortage of IPv4 addresses and I was trying to be a good citizen.

So much for being a good citizen.
I just spoke to Zen and this is still on offer to new customers, but as I was a good citizen I am being punished with a £30 admin fee. Well done Zen. However I could cancel and re subscribe to get the same thing. Awful lot of effort, why not offer it for as a free regrade like Zen have done in the past. I if was cynical I would say when it suited Zen.

My situation is I am running a number of services from my 1 IP address via NAT, and IIRC when you get 8 the tops and bottom address are for network addressing , one is for the router and the other 5 are allocated by the router ? Am I still correct here?

This got be thinking about IPv6 If I have Zen enable IPv6 I believe I get 65536 ipv6 addresses, an my router is responsible for management. I also keep my one IPv4 address. My question is about translation,. What technology do zen use for translating the ipv4 to ipv6 for both incoming and outgoing calls, and will this affect any services I currently run on IPv4. Also could I host these on IPv6 and how do Zen do the translation from IPv4 clients.


Kind Regards
Andrew

Zen's IPv6 implementation will give you a static /64 and a static /48. The /64 is used solely for the WAN interface of your router. The /48 is for delegation to your LANs - this gives you 2^16=65536 /64s. A /64 is the smallest prefix allocation normally used on IPv6 other than for point to point links, not least because it's the smallest allocation over which SLAAC works. SLAAC is way that many IPv6 devices acquire their address(es).

A /48 is a large allocation, but not unusual for IPv6. That said, I think there are very few Zen ADSL and FTTx customers whose would find a /56 limiting - that's 2^8=256 /64s. There is no need to scrimp over IPv6 addresses at this stage, and certainly not adopt the practices of some ISPs in the US, which only give a dynamic /60 or, worse still, a dynamic /64, causing all manner of implementation problems. However, even with the somewhat wasteful way I use IPv6, I'm only using five /60s from the sixteen available in the lowest /56 in my /48 allocation. I've deliberately restricted my usage to that lowest /56, so that the remaining 255 /56s could be handed back to Zen in the future without me having to reconfigure anything. I'd encourage anyone else implementing IPv6 on their networks to stick to a similar arrangement, rather than spreading their usage throughout their allocation.


It is best to think of the IPv4 Internet and IPv6 Internet as entirely separate. Translation mechanisms exist to allow some IPv4 endpoints to initiate a connection to an IPv6 endpoint, but many IPv4 endpoints have no way of accessing an IPv6 endpoint. An IPv6 endpoint wishing to initiate a connection to an IPv4 endpoint needs a NAT64 - and I don't believe Zen runs a customer NAT64.

I would encourage you to enable IPv6 if you have a suitable router, then run your devices "dual stack", with both an IPv4 and IPv6 address. The time will come when there are endpoints on the Internet with no IPv4 connectivity that you wish to access, and the best way to prepare for that is for your devices to have native IPv6 enabled. To prepare for endpoints wishing to connect to your network that are IPv6 only, it is best to run any services, such as mail or web servers, on both IPv4 and IPv6.


If NAT with port translation is inadequate for what you want to do over IPv4, your only option is to request a regrade from your single IPv4 address to a /29 (8 IPv4 addresses). I believe Zen have now removed the option of a free /29 at sign up: all new accounts get a single static IPv4 address unless they specifically request and order another option at the prevailing price. I suspect a lot of the people who ordered a /29 when it just required selecting a free-of-charge option at sign up did so because it seemed like a good idea, but have only ever used the gateway address, wasting the rest of the block. Consumer routers typically make the use of anything other than a single IPv4 address on the WAN side difficult or impossible, especially if you want the router to provide NAT for all devices that lack a dedicated IPv4 address.

Now that we've reached IPv4 exhaustion, Zen will be wanting to conserve IPv4 addresses so that they can continue to sign up new customers with a single static IPv4 address. I guess a £30 fee for a /29 is seen as sufficient to discourage those who do not really need a /29. I suspect this fee might also apply to new customers wanting a /29.

For good reasons, I had to move from the free /29 I got at sign up many years ago to a /28 (16 IPv4 addresses) many years ago. Allocation of a /28 or larger block required a RIPE form and a fee some way over the £30 you say Zen are now charging for a /29.


The lowest address of an IPv4 subnet is the network address, and the highest address is the broadcast address. Strictly speaking, neither of these addresses can be used, though it there is normally no barrier to using the network addresses of an allocation smaller than a /24 with 1:1 NAT so long as the address isn't x.y.z.0 or x.y.z.255. If possible, it's best to leave the network and broadcast addresses unused.

Zen use the highest address of your IPv4 block other than the broadcast address as your gateway address - this will be the address allocated to your router via IPCP. It is important not to configure a static IPv4 address in the PPPoA or PPPoE settings of your router, as Zen use a dynamic gateway address. As with a single IPv4 address, Zen will always allocate the same address to your router via IPCP. Every router I've come across allows you to use this gateway address for NAT, just as you do with a single IPv4 address.

Once you've allowed for the network address, subnet address and gateway address (which you can almost certainly use for NAT), you have five addresses remaining from a /29. These can be allocated in any way you choose. Exactly how you use them depends on your router and the arrangement of your internal network(s).

Thanks David excellent explanation,

So I should consider IPv4 and IPv6 not seamlessly accessible from each other, fair enough, seems reasonable.

If you buy a new contract from Zen you will be offered 8 IP free even now.
If I cancel and then take out a new contract I can get 8 IP now free. IIRC the sales persons comment was something along the lines of I can�t direct you to take that approach. Because I was a good citizen Zen now want to charge to enable the 8 static IP addresses. Not good

Kind Regards
Andrew

For what it's worth, I don't think the £30 admin fee is anything new. I recall it being there as far back as 2007.

Remember... If you cease & re provide you will end up paying more. It sounds like a lot of messing round to leave for another provider only to come back. I'd pay the admin fee myself.

And as others have said - I think the cost of a IP regrade has been there for a very long time.

This started off as a technical question with a bit of a moan about regrades. I think some people are misinterpreting my emails. I have too much invested to just leave for £30. The point is one of principle.

When I was a new customer many years ago and new customers today are offered 8 IPs free. Being a good citizen I choose not to take the 8 IP addresses I did not need at the time especially given the shortage of IPv4 addresses. Whereas some people I would imagine just clicked on yes I have it as it�s free. May be I should have done that taken what I do not require, is this the way the world is going? If there was a £30 fee for new or existing customers then I would understand it given the limited IPv4 addresses.

Also while I can also understand admin charges they are everywhere. I have had multiple no charge regrades across my multiple accounts I have with Zen , from memory there was the FTTC1 � FTTC2 upgrade, ADSL Pro ( If I remember the name correctly) to ADSL unlimited. No charges for any of these perhaps the first one was good advertising for Zen and the 2nd was getting old products of their books.


Rant over�.

This is going to bug you big time.

Initial service started with Zen in April 2014. Like you, I opted for a single IP.

Called them up Feb 2015 to enquire about regrading to 8 IPs. A very helpful polite young woman answered (after a long ring-wait time) and I enquired, already stating I know that it's chargeable (as I'm way past the initial 30-days of being a new customer) and the response was "oh I can put that through for you now, no charge...."

And so it was done.

It does appear to be a bit hit and miss. Though I was still in contract at this point (around 2 months left) so maybe that is why she waived the fee.

I'm sorry they appear to be this strict in your case. Understandable for a greater than 8 IP regrade (16, 32 etc) where the fees are clearly on their website, but in this case, I just don't get it.

Thanks It made me smile I can quite believe it

I really do believe its down to the people on the end of the phone. Some follow the strict guide (Larger companies script based calls) others can see sense / be flexible (like I thought Zen were), usually only those with the power to offer / experience act this way.

Any one from Zen care to help ?

Andrew

An admin charge for a change is not unreasonable or unusual, sometimes they may chose to wave the change. Its not a simple change e.g. not just be a click of a button. the £30 fee will be less than it costs them to arrange and do the work.

The company I work for charges much more for much simpler changes.

I'd be surprised if it was any more complicated than a simple button press actually.

I had a lot of help trying to get IPv6 working (failed in the end) including an offer to completely change my IP range.

It seems odd that they would charge for a simple IPv4 change but are willing to do far more complicated fiddling with IPv6 for free.

Personally I would probably persist in hounding them and asking politely if this could be raised higher in the company. It may help if you can give a good reason for why you actually need them.

Edited by alexatkin (Thu 11-Aug-16 01:03:42)