North American Network Operators Group

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Re: IPv6 news

  • From: Andre Oppermann
  • Date: Tue Oct 18 10:53:20 2005

[email protected] wrote:
Right, cause phone number portability is up and running for several
of prefixes in various regions across the world[1], so there's definitely nothing we can learn from them. ;)
Well, we can learn from them that circuit switched networks are different
than packet switched networks. Beyond that not much.
I disagree. There are many parallels and in many ways the telephony operators are struggling with the same kinds of
problems that we are. NANPA has forecast that the North
American number plan will be exhausted within 20 years.
Just like the IPv4 address space.

Their plan is to extend the number plan by two digits
using 4-digit area codes and 4 digit central office
codes. Rather like IPv6's extended address length.
The new digits will be introduced at the same time
so that everyone will dial an extra digit at the end
of their existing area code, and another extra digit
at the beginning of their central office code. Today
you would dial (703)227-0660 to reach ARIN's help
desk. After the change you would dial (7030)0227-0660.
Full details here:

NANPA's website points to more information.

There is also a North American Numbering Council that meets regularly and has several working groups.

It is foolish to regard people outside the IP
networking industry as inferior. Good ideas can
come from anywhere and we can often understand our
own area of interest much better by comparing and contrasting with other similar areas of interest.
There is a major difference between phone numbers and IP addresses
which makes direct comparisons harder.  Phone numbers are more like
Domain names (+email addresses behind them) than IP addresses.  People
use phone numbers the same way they use domain names.  They remember
them and use them to access other people, or companies.  I haven't
seen many billboards with IP addresses on them lately. Nobody cares
about the actual IP address.  Only the computer does at the time of
the DNS lookup.

So an IP address is only used as underlying transport vehicle of
data.  For the enduser it doesn't have any direct significance.

A phone number has significance to the end user and has a hybrid
function as underlying routing element to varying degrees too.

The entire problemset with IP address portability comes from two
issues: Ease of ISP changes and redundant connectivity.  The former
could theoretically be solved with with better procedures and methods
for host address assignment.  However it still requires some labor
intensive transition period and the IP addresses are much tangled with
other things like DNS and so on.  The second issue is IP architecture
specific.  The PSTN, due to its symmetric nature, doesn't have the
redundancy problem to the same extent as the Internet.  For the
IP prefix however you have to participate in the global routing
system to survive link losses.  Without any shim6 or SCTP stuff
that is.

Again, phone numbers and their portability can and should not be
compared with the IP address portability issues.  They're very
different animals.