[Serusers] Re: [Serdev] ENUM issues - req. for discussion

[Juha Heinanen]

Andrei Pelinescu-Onciul writes:

 > This could be fixed by limiting the ammount of time that a dns lookup
 > can take in ser (e.g. a new config parameter).

that kind of parameter would indeed be a good thing.  slow dns query has
nothing special to do with enum.  it would affect also lookups on
request uri host.

 > > This may result in a failed transaction, or like revealed at the 
 > > ENUM plugtest in failed accounting. 

accounting should succeed.  failure may be result of yet another bug in
radiusclient library, not necessarily in ser.  i asked more details
about this incident, but i guess adrian has been too bury to provide
it.
 
 > > Thus you can't avoid doing some URI checks against the URI received from 
 > > the ENUM lookup. Perfomance issues are no valid arguements! Once I give 
 > > control to external services (DNS, radius, exec), the perfomance 
 > > penalties due to parsing the SIP URI are much more less than due to the 
 > > ENUM lookup.
 > 
 > What kind of checks? Run parse_uri and if fails return an error?
 > This will happen any way at the first forward attempt that takes uri
 > into account (the forward will fail).

this is what i said too.  i could try to parse every uri returned from
enum, but i have considered it waste of time, because bad uris will be
detected later anyway either by ser or, in case of 302, by sip ua.

 > This could be easily done, but as I said above, if the uri is bad
 > forwarding will fail anyway.

exactly.

-- juha