On 02/27/2018 12:52 PM, Aaron Gould wrote:
Thanks
For #2 – what if the ports allocated aren’t enough for the amount of inet
traffic the customer site uses ? …is the customer denied service based on
insufficient port range ? …or are they assigned another block within that some
ip’s range of I think it’s 0-64k or 1025-64k… but how far can you take that
before there aren’t anymore port blocks left on that single ip ? …and if you
have to allocate that customer another port block from a *different* ip, then
we are in the situation of the bank website not liking the fact that the
session is bouncing to a different ip maybe ?
Yes, common problem, and the session just fails (TCY SYN dropped)
because of insufficient ports.
Most CGNs allow you to configure a range of ports for a customer, and
reserve an additional range if they need more ports. Yes, if you
allocate 1000 ports for one IPv4 address to each of 50 customers and
they all need hundreds more ports than that, you're going to run out of
ports and connections fail.
This is why you have IPv6. Even while many web sites and apps don't
support IPv4, enough do that it relieves some pressure on your CGN.
Lee
- Aaron
From: Michael Crapse [mailto:mich...@wi-fiber.io]
Sent: Tuesday, February 27, 2018 11:19 AM
To: Mike Hammett
Cc: Aaron Gould; NANOG list
Subject: Re: cgnat - how do you handle customer issues
For number 2, I'm a fan of what mike suggests. I believe the technical term is
MAP-T.
For number 1, anyone who wants one, gets one. We provide free public static IP
to any customer who asks for one. Another solution, using above solution is to
ask them which ports they need, and forward those to them using a port within
their assign range. i.e. teach them how to access their home web server using a
different port(say 32424, or similar). This won't solve all the issues, which
is why we use solution 1.
On 27 February 2018 at 09:32, Mike Hammett <na...@ics-il.net> wrote:
I'm a fan of nailing each customer IP to a particular range of ports on a given
public IP. Real easy to track who did what and to prevent shifting IPs.
-----
Mike Hammett
Intelligent Computing Solutions
Midwest Internet Exchange
The Brothers WISP
----- Original Message -----
From: "Aaron Gould" <aar...@gvtc.com>
To: Nanog@nanog.org
Sent: Tuesday, February 27, 2018 10:30:21 AM
Subject: cgnat - how do you handle customer issues
Couple questions please. When you put thousands of customers behind a cgnat
boundary, how do you all handle customer complaints about the following.
1 - for external connectivity to the customers premise devices, not being
able to access web servers, web cameras, etc, in their premises?
2 - from the premise natted device, when customers go to a university or
bank web site, how do you handle randomly changing ip addresses/ports that
may occur due to idle time and session tear-down in nat table such that the
bank website has issues with seeing your session ip change?
-Aaron
