[Standards] UPDATED: XEP-0156 (A DNS TXT Resource Record Format for XMPP Connection Methods)
stpeter at jabber.org
Tue Jan 30 23:18:21 UTC 2007
Hi Matthias, as usual you are right...
Matthias Wimmer wrote:
> XMPP Extensions Editor schrieb:
>> Abstract: This document defines a DNS TXT Resource Record format for
>> use in specifying methods of connecting to an XMPP server.
>> Changelog: Removed _xmpp-client-tcpssl attribute since use of the
>> old-style SSL-only port is discouraged. (psa)
> Could we please remove _xmpp-client-tcp and _xmpp-server-tcp as well? I
> very much feel, that these records are not good.
The justification I have heard for _xmpp-client-tcp is the lack of SRV
support in client-side libraries.
> Especially the
> _xmpp-server-tcp record is very bad.
Yes I think _xmpp-server-tcp is really not needed. Push your service
provider to support SRV. Server-side code should have access to a
library that has SRV lookups (unlike client libs).
> For compatibility we already have to do up to four DNS lookups:
> _xmpp-server SRV
> _jabber SRV
Let's deprecate _jabber SRV, shall we? I have already removed any text
about it from rfc3920bis (version -01).
> Especially with slow nameservers this can take some time until the
> connection is established.
> Even if the _xmpp-server-tcp TXT record is discurraged, it only makes
> sence to have it, if we REQUIRE servers to look it up. (Not requiring
> this lookup would make the record completely useless and making servers
> using it only available for a subset of the Jabber network.)
> I don't think we sould introduce new records, that are discouraged to be
> used from the beginning. Better we should start working at stopping to
> support the old _jabber SRV record and focusing on _xmpp-server SRV.
> For _xmpp-client-tcp the disadvantages are not that problematic as
> typically only a single serie of lookups is required at the startup of
> the client. But still I think having a _xmpp-client-tcp TXT record type
> only makes everything more complicated and we should not introduce
> something that is discouraged from the beginning. And it confuses
> admins, that try to use the records and have to notice, that most
> clients will not support it (as usage is discouraged). One example for
> this can be currently seen on the jadmin list.
I don't have a strong argument against your reasoning. It's certainly
not a hill for me to die on.
Even the TXT records for things like http binding will be deprecated
eventually if U-NAPTR takes off. But that might take a while. In the
meantime, the TXT lookups for http binding etc. are helpful.
XMPP Standards Foundation
-------------- next part --------------
A non-text attachment was scrubbed...
Size: 7358 bytes
Desc: S/MIME Cryptographic Signature
More information about the Standards