The fact remains, and it is a fact, that the allocation of static IP addresses decreases the size of the allocatable pool. That was all I said, as an additional factor in them running out of a large enough free pool.

The only possible question can be as to whether or not Plusnet have available a total number of IP addresses greater than their total number of customers. That we don't know, but it's unlikely. A few years ago it was not the case with any ISP - it would remove the need for dynamic allocation, so why keep it if they have?

Their dynamic ones are certainly very non-sticky. Every re-sync or reboot will get a new one. Plenty of people with one do those for all sorts of reasons.

When the "online" graph was available it varied by only a few thousand over 24 hours. That means I do accept that most people leave their modem on overnight. But not all, and not all leave it on all day.

You may be surprised at my initial statement. But it was true. I, in my turn, am surprised you even thought it worth disputing. It's completely irrelevant to an answer to the original question by the OP, which I successfully supplied.

In reply to a post by RobertoS:

The fact remains, and it is a fact, that the allocation of static IP addresses decreases the size of the allocatable pool. That was all I said, as an additional factor in them running out of a large enough free pool.

If you have 2500 customers, you need 2500 IP addresses for those customers. It doesn't matter if 500 of them have essentially the same one provided all the time and the other 2000 have different ones each time they connect - you still need 2500 IP address. If you then sign up another 500 customers you need another 500 IP addresses. You cannot get away with only 300. That is what the dial up world used to do. Every ISP supplying any form of broadband has to have a 1:1 relationship between customer accounts and IP addresses.

Unless you use CGNAT.

The only possible question can be as to whether or not Plusnet have available a total number of IP addresses greater than their total number of customers. That we don't know, but it's unlikely. A few years ago it was not the case with any ISP - it would remove the need for dynamic allocation, so why keep it if they have?

You assume dynamic allocation saves IP addresses. It does not. Unless people are still using "usb frog" type modems for ADSL, the concept of the WiFi router and people using Smart TVs, phones tablets etc, means that every account is always connected.

Their dynamic ones are certainly very non-sticky. Every re-sync or reboot will get a new one. Plenty of people with one do those for all sorts of reasons.

Mostly for a completely unaware concept of security. (hint: hackers don't follow an IP).

You may be surprised at my initial statement. But it was true. I, in my turn, am surprised you even thought it worth disputing. It's completely irrelevant to an answer to the original question by the OP, which I successfully supplied.

Yes, I thought it would be a short side thread

In reply to a post by RobertoS:

The only possible question can be as to whether or not Plusnet have available a total number of IP addresses greater than their total number of customers. That we don't know, but it's unlikely. A few years ago it was not the case with any ISP - it would remove the need for dynamic allocation, so why keep it if they have?

I would imagine most ISPs (of this type, and not doing CGNAT) have more free IP addresses than their customer-base, there can't be many <2%? of customers who are switching routers on and off at night and it would be really risky and foolish for an ISP to run with so little free addresses such that if a few customers started using the internet at once then they would run out of addresses. For example they can be certain that on Christmas day most customers will be switching their routers on to send pointless emails to family members etc.

Having dynamic pools does make it easier to shift IP addresses around more easy though as customers can't then kickup a fuss when their static IP changes.

In reply to a post by Pipexer:

Having dynamic pools does make it easier to shift IP addresses around more easy though as customers can't then kickup a fuss when their static IP changes.

It was also a way of stopping people running servers at home for some ISPs who changed the IP more frequently.

The only thing it stops running is BQM.

It's rather easier to administer dynamic IPs. There's little config information to keep and you don't require a system to recycle IP addresses when you lose a customer. So there's virtually not saving in actual IP addresses required, but it's still probably simpler.

I'll go along with that.

Looks like I'm wrong wrt to the way things work these days. I assume you've seen my thread on Gen Chat where kitkat has an in-depth version of some administration points raised here.

My apologies.

/dodderingoldgit slinks away....

In reply to a post by RobertoS:

Looks like I'm wrong wrt to the way things work these days. I assume you've seen my thread on Gen Chat where kitkat has an in-depth version of some administration points raised here.

My apologies.

/dodderingoldgit slinks away....

I hadn't seen the thread, and thanks for the pointer. kitcat brings up some more complex issues but the encapsulation of IP inside PPP does help ISPs such as Plusnet as they can route the end customers IP address through any of their gateways.

But yes, the simple answer is majority stay connected, and then you need some more to handle your various gateways (BT's @hgXX or plusnet's BNG's etc).

ISP networks are seriously complex; I'm only working on the edge of big corporate networks but have seen enough to know handling the gigabits of traffic that Openreach and the ISPs handle is complex.

I think the biggest reason for not making static standard policy is to differentiate between consumer and business services. This is a comment across the industry as a whole not plusnet, as plusnet go against this trend offering static for a very small cost.
Dynamic also probably allows more flexibility in configuration and management, but I have a feeling this isnt the prime reason.