Kitz ADSL Broadband Information
adsl spacer  
Support this site
Home Broadband ISPs Tech Routers Wiki Forum
 
     
   Compare ISP   Rate your ISP
   Glossary   Glossary
 
Please login or register.

Login with username, password and session length
Advanced search  

News:

Author Topic: Help needed to ascertain WAN IP lease times for various ISPs  (Read 3400 times)

broadstairs

  • Kitizen
  • ****
  • Posts: 3697
Help needed to ascertain WAN IP lease times for various ISPs
« on: December 21, 2017, 10:25:36 AM »

I have had a thread running on the short WAN lease times used by TalkTalk and they have suggested that this 15 minute (900 second) is normal for ISPs to preserve IPv4 addresses. I really cannot believe that most ISPs have such short lease timings, if a router behaves correctly it will renew the lease at 50% of the lease time which in this case means every 7.5 minutes.

Can people here please take a look at their routers to see if they can ascertain their lease time for their IPs? I'd like to hear from as many as possible including other TT users. For ZyXEL users the way to find this is to use the router log and set to record WAN DHCP entries. I'm not sure if other routers may show this on a status page somewhere, otherwise a log seems to be the way to go to view this.

Stuart
Logged
ISP:Vodafone Router:Vodafone Wi-Fi hub FTTP

jaydub

  • Reg Member
  • ***
  • Posts: 351
Re: Help needed to ascertain WAN IP lease times for various ISPs
« Reply #1 on: December 21, 2017, 01:01:29 PM »

No WAN DHCP option on my ZyXel VMG8924.  I have DHCP Client and DHCP Server options ticked.  The log file for DHCP server contains DHCP requests from devices on the LAN as you might expect.  There is nothing in the DHCP client log file.  ISP=IDNet.
Logged

renluop

  • Kitizen
  • ****
  • Posts: 3326
Re: Help needed to ascertain WAN IP lease times for various ISPs
« Reply #2 on: December 21, 2017, 04:23:42 PM »

From a 2016 post on Plusnet Commumity
Code: [Select]
The WAN IP you're assigned should only change on a reconnection, so indefinite time.
Logged

Jasonkruys

  • Reg Member
  • ***
  • Posts: 101
Re: Help needed to ascertain WAN IP lease times for various ISPs
« Reply #3 on: December 21, 2017, 04:28:18 PM »

Sky's appears to be 90 minutes on my FTTC connection
Logged

Chrysalis

  • Content Team
  • Addicted Kitizen
  • *
  • Posts: 7382
  • VM Gig1 - AAISP L2TP
Re: Help needed to ascertain WAN IP lease times for various ISPs
« Reply #4 on: December 21, 2017, 06:10:14 PM »


sky seems to be 4 hours as i get renew every 2 hours on ipv4

this is on pro with dhcp preservation (static)
« Last Edit: December 21, 2017, 06:13:25 PM by Chrysalis »
Logged

ejs

  • Kitizen
  • ****
  • Posts: 2078
Re: Help needed to ascertain WAN IP lease times for various ISPs
« Reply #5 on: December 21, 2017, 06:54:37 PM »

I think this will not apply to ISPs who use a PPP connection, where the WAN IP is assigned using IPCP while establishing the PPP connection.
Logged

broadstairs

  • Kitizen
  • ****
  • Posts: 3697
Re: Help needed to ascertain WAN IP lease times for various ISPs
« Reply #6 on: December 21, 2017, 09:16:40 PM »

It is beginning to seem to me that TT are likely to be way out of line with 15 minutes. I simply cannot see the benefit of such a short lease time. Even a couple of hours would seem more reasonable to me. Still thanks to all who have commented so far but I still hope for some further reports.

Stuart
Logged
ISP:Vodafone Router:Vodafone Wi-Fi hub FTTP

tubaman

  • Senior Kitizen
  • ******
  • Posts: 12507
Re: Help needed to ascertain WAN IP lease times for various ISPs
« Reply #7 on: December 22, 2017, 08:05:12 AM »

No sign of any renewal attempt on my BT FTTC connection in the last 24 hours.
 :)
Logged
BT FTTC 55/10 Huawei Cab - Zyxel VMG8924-B10A

adrianw

  • Reg Member
  • ***
  • Posts: 163
Re: Help needed to ascertain WAN IP lease times for various ISPs
« Reply #8 on: December 22, 2017, 09:45:04 AM »

As others say, there is only activity in my pfSense PPPoE logs for two lines (Plusnet and AAISP) with bridged modems when the line resyncs. One was over a month ago, the other a couple of days ago.
Logged

renluop

  • Kitizen
  • ****
  • Posts: 3326
Re: Help needed to ascertain WAN IP lease times for various ISPs
« Reply #9 on: December 22, 2017, 03:25:20 PM »

Same IP since
20 Dec 2017 07:01:43
Logged

broadstairs

  • Kitizen
  • ****
  • Posts: 3697
Re: Help needed to ascertain WAN IP lease times for various ISPs
« Reply #10 on: December 22, 2017, 03:36:21 PM »

I now have had some sense from the TT network team. Why this cold not have been explained earlier is beyond me:-

Quote
Our Network Service Team have provided the following information to address the points you've raised
Sky are the only other operator who use DHCP for subscriber termination in volume. BT, Plusnet and AAISP all use PPP PPP has more keep alives than DHCP – traditionally one PPP LCP keepalive per 30 seconds; some other operators go as low as ever second – so we are not putting undue load on the network or CPE – quite the opposite in fact. Shorter lease times mean greater recovery if things go wrong - as we are only waiting 15 minutes for a lease to expire – not an hour.

So that explains what is going on here. I suspect that those here who do not see DHCP renews will if they are able to investigate see PPP keep-alive which as they explain is more of a load as it happens quite often.

Now as to what effect this may be having I am not sure. I do see quite often pauses when accessing the web which I thought might be associated with this activity  as it only happened every few minutes but on further investigation I am now pretty sure the problem is with my wireless network and not the router connection.

Stuart

[Moderator edited to fix the problem with the [/quote] tag.]
« Last Edit: December 22, 2017, 05:20:12 PM by burakkucat »
Logged
ISP:Vodafone Router:Vodafone Wi-Fi hub FTTP