Subject: [port-srv-reg] Survey of current service (port) names

From: Stuart Cheshire <[email-masked]>
Date: Wed, 25 Mar 2009 11:46:15 -0700

Since none of us could remember this morning how many exceptions there  
are to the service name rules, I decided to do a quick check.

Note that <http://iana.org/cgi-bin/usr-port-number.pl> says:

> What SHORT name (14 CHARACTER MAXIMUM) do you want associated with  
> this port number? (For example: sums)

I pulled down <http://www.iana.org/assignments/service-names> and <http://www.iana.org/assignments/port-numbers 

All names in the service-names list are legal according to our new  
rules: LHD, only interior hyphens, 14 characters or less.

The port-numbers list is more interesting. Of the service (port) names  
listed here:

* 10,299 entries have legal names
*    162 were legal except for containing underscores
*     92 were legal except for being 15 characters long
*      7 were legal except for containing underscores *and* being 15  
characters long
*     16 contained other invalid characters: + * / .
*      0 were longer than 15 characters

Here are the ones with invalid characters

whois++          63/tcp    whois++
whois++          63/udp    whois++
sql*net          66/tcp    Oracle SQL*NET
sql*net          66/udp    Oracle SQL*NET
cl/1            172/tcp    Network Innovations CL/1
cl/1            172/udp    Network Innovations CL/1
z39.50          210/tcp    ANSI Z39.50
z39.50          210/udp    ANSI Z39.50
914c/g          211/tcp    Texas Instruments 914C/G Terminal
914c/g          211/udp    Texas Instruments 914C/G Terminal
novell-lu6.2    1416/tcp   Novell LU6.2
novell-lu6.2    1416/udp   Novell LU6.2
EtherNet/IP-1   2222/tcp   EtherNet/IP I/O
EtherNet/IP-1   2222/udp   EtherNet/IP I/O
EtherNet/IP-2   44818/tcp   EtherNet/IP messaging
EtherNet/IP-2   44818/udp   EtherNet/IP messaging

If we want to be lazy, we can allow 15 characters and underscores, and  
then we only have eight to fix by hand.

If we want to be strict we have more work do to: 162 to rename by  
mapping underscore to hyphen, 92 to truncate down to 14 characters,  
and 7 to map and truncate.

Stuart Cheshire <[email-masked]>
* Wizard Without Portfolio, Apple Inc.
* Internet Architecture Board
* www.stuartcheshire.org

---

From: Stuart Cheshire <[email-masked]>
Date: Thu, 26 Mar 2009 10:09:07 -0700

> The port-numbers list is more interesting. Of the service (port)  
> names listed here:
>

I meant to include the actual text files with my last email, but  
forgot. Here they are.

---

From: Joe Touch <[email-masked]>
Date: Thu, 26 Mar 2009 11:11:18 -0700

Hi, all,

I'm wondering what specific requirements limit hostnames to 14
characters, and if it'll break anything to allow 15-character service
names or longer.

The DNS allows labels of 63 characters or less (RFC1035).

Hostnames are as follows (case-insensitive):

	[a-z0-9]([a-z0-9\-]*[a-z0-9])?

I'm wondering if we can allow strings with the hostname syntax limited
to 63 characters max, with 14 or less preferred as a current
recommendation (but not limitation).

Joe