Re: [port-srv-reg] Four final points for discussion

[Joe Touch <[e-mail]>]

Hi, all,

On 9/7/2010 4:16 PM, Stuart Cheshire wrote:
> On 3 Sep, 2010, at 01:31, Alexey Melnikov wrote:
>
>>>> 2. Service Name Rules
>>>>
>>>> I liked Joe's earlier suggestion to disallow all-numeric service
>>>> names, to avoid service names that look like a numeric port number.
>>>> However, even with that rule, we still allow service names like
>>>> this: "6000-6063" (looks like the X Window System port range). Do we
>>>> care? We could prevent that by requiring that all service names
>>>> contain at least one alphabetic character.
>>>>
>>> I like that proposal.
>>>
>> Fine with me.
>
>
> I've made this change. The text now says:
>
> Valid service names:
>
> o MUST be at least 1 character and no more than 15 characters long
>
> o MUST contain only US-ASCII [ANSI.X3-4.1986] letters 'A' - 'Z' and
> 'a' - 'z', digits '0' - '9', and hyphens ('-', ASCII 0x2D or
> decimal 45)
>
> o MUST contain at least one letter ('A' - 'Z' or 'a' - 'z')
>
> o MUST NOT begin or end with a hyphen
>
> The reason for requiring at least one letter is to avoid service
> names like "23" (could be confused with a numeric port number) or
> "6000-6063" (could be confused with a numeric port number range).

But 3-4-5 can't be confused with a range, nor would 6000-45. AFAICT, 
range-like entries can and should be avoided by the registration 
procedure, the same way we avoid double hyphens that look too similar to 
single-hyphen names already registered.

FWIW, I still don't like adding the "must have at least one alpha" rule, 
but IF we keep it, here's the ABNF:

	NAME = *(1*NUM [HYPHEN]) ALPHA *([HYPHEN] 1*ALPHANUM)

> Although service names may contain both upper-case and lower-case
> letters, case is ignored for comparison purposes, so both "http" and
> "HTTP" denote the same service.

Service names are already noted as case-insensitive. We typically record 
them in the database in lower case only; we do NOT retain any case as 
provided by the registrant to discourage the notion that case matters.

Joe