Subject: [Ecrit] ECRIT client implementation report

From: Richard Barnes <[email-masked]>
Date: Mon, 12 Apr 2010 10:00:21 +0300

Executive summary:
We built a bare-bones ECRIT client in around a week's worth of labor.

Full report:

Just a quick note to relate some recent experience implementing ECRIT:  
A colleague and I just spent some time extending the SIP Communicator  
multi-protocol client [1] so that it can place calls to service URNs  
using the ECRIT system.  It's not phonebcp compliant (e.g., since we  
probably don't do anything that's in ED-65), but at least you can talk  
to a PSAP:  It turns a service URN into a SIP URI and places a call to  
it.

Our starting point was the "Internet Geolocation Toolkit" (igtk [2]),  
the HELD/DHCP location client we've been working on.  The client  
itself is written in C++, but we've got a Java version via SWIG.   
Starting from there, here's the time it took, in man-hours:

16 hr  Figuring out SIP Communicator's architecture
  4 hr  Adding a location plug-in to expose igtk to SIP Communicator
  8 hr  Adding an "ECRIT resolver" to do LoST mapping
  8 hr  Integrating the ECRIT resolver into the call path
=====
36 hr  TOTAL

What it doesn't do:
-- LoST discovery
-- LoST number recognition
-- LoST <listServicesByLocation>
-- Any ECRIT-specific SIP things (e.g., including service URN or  
Geolocation)
What it does do:
-- LIS discovery and HELD
-- DHCP geolocation options
-- LoST <findService> query
-- Place SIP call to PSAP URI from LoST

You can even add urn:service:sos.police as a "buddy" :)

I hope to have the source code posted in the next update to igtk,  
which should be in a few weeks.

Cheers,
--Richard

[1] <http://www.sip-communicator.org/>
[2] <http://igtk.sourceforge.net/>