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<DIV><FONT face=Arial size=2>All,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I'm haveing a bit of trouble getting my head around
H.323 and call routing with Gatekeepers, Zones and intra-zone calls - hopefully
someone who is more informed in things H.323 will be able to point me in the
right direction...?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I already have a mature network of Asterisk boxes
dotted around the UK and overseas with hundreds of extensions and our own
number-plan/dial-plan in the form 8EEXXXX where 'EE' is a two digit "exchange
number" and 'XXXX' is the four digit extension number, so for example my desk
phone (a Cisco 7970G as it happens) at home is 8202001 and other phones around
the house 8202002, 8202003 etc.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I have a Cisco 2621XM connection to the internet
with NM-2V and some VIC-2E&M cards and have my home Asterisk box hooked up
to ham radio and other interesting audio sources which I use Asterisk ooh323 to
make H.323 connections to the Cisco and its simple, reliable and just
works.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I'm working on an R&D project with TETRA -- a
digital trunked radio system -- the hardware of which comes from Damm Cellullar
(<A href="http://www.damm.dk">www.damm.dk</A>) and is called TetraFlex - the
system supports point-to-point (half duplex), group comminication and PABX/PSTN
interconnect via H.323. Further investigation shows the system controller
to be built on Windows-XP embedded and use the OpenH323 stack to provide H.323
connectivity, however the use of a Gatekeeper is mandatory in their set
up.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So, I have the following:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>- a network of Asterisk boxes using 8EEXXXX
numbering with IAX2 between sites, hundreds of SIP and SCCP phones</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>- a TETRA system using 'mobiles' that I have
numbered 817XXXX to fit my number plan, a H.323 setup that requires a
Gatekeeper</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>- an Asterisk box (1.2.14 + asterisk-addons-1.2.5)
on the same LAN segment as the TETRA system with OOH323 compiled up and
working</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>
<DIV>- the devices are as follows:</DIV>
<DIV> </DIV>
<DIV> 192.168.1.5 is the
Asterisk box</DIV>
<DIV> 192.168.1.6 is the
Cisco 2621XM GateKeeper</DIV>
<DIV> 192.168.1.7 is the
Damm TETRA system</DIV></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Where I am "stuck" is partly with the H.323
concepts and partly with the implementation...</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>First I went in search of a H.323 Gatekeeper and
tried to build the GNU GK from source on another Fedora Core 6 box which turned
out to be a nightmare (missing libraries, the OpenH323 libraries appear to be
deprecated in favour of Opal? conflicting versions of pwlib, problems with
yacc/bison building the ASN.1 parser, etc. etc.) so next I turned to
Cisco. I have a spare 2621XM router with c2600-jsx-mz.123-22.bin which
includes a H.323 gatekeeper... great... so I've configured it up (all three
lines of it :o) so far:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> !</FONT></DIV>
<DIV><FONT face=Arial size=2> gatekeeper<BR>
zone local TETRA tubby.org 192.168.1.6<BR> no
shutdown<BR> !</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>and can get both Asterisk and the Damm TETRA
equipment to register with the Gatekeeper, like this:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV><FONT face=Arial size=2>
<DIV><BR> router-h323-gw#show gatekeeper endpoints</DIV>
<DIV> </DIV>
<DIV>
GATEKEEPER ENDPOINT REGISTRATION<BR>
================================<BR> CallSignalAddr
Port RASSignalAddr Port Zone
Name Type
Flags<BR> --------------- ----- --------------- -----
--------- ----
-----<BR> 192.168.1.5 1720
192.168.1.5 13030
TETRA
UNKN-GW<BR> H323-ID: PABX</DIV>
<DIV> H323-ID: Asterisk</DIV>
<DIV> E164-ID: 100<BR>
Voice Capacity Max.= Avail.= Current.=
0<BR> 192.168.1.7 1720
192.168.1.7 1085
TETRA
UNKN-GW<BR> H323-ID:
DAMM<BR> Voice Capacity Max.=
Avail.= Current.= 0<BR> Total number of active
registrations = 2</DIV>
<DIV> </DIV>
<DIV> router-h323-gw#<BR></DIV>
<DIV> </DIV>
<DIV>Over at the Asterisk box I have the following in ooh323.conf:</DIV>
<DIV> </DIV>
<DIV> [general]<BR> ;Define the asetrisk
server h323 endpoint</DIV>
<DIV> </DIV>
<DIV> bindaddr=0.0.0.0<BR> port=1720</DIV>
<DIV> </DIV>
<DIV> gateway=yes</DIV>
<DIV> </DIV>
<DIV> h323id=Asterisk<BR> e164=100</DIV>
<DIV> </DIV>
<DIV> gatekeeper = 192.168.1.6</DIV>
<DIV><BR> [cisco-gk]<BR>
type=peer<BR> ip=192.168.1.6<BR>
port=1720<BR> context=from-h323<BR>
disallow=all<BR> allow=alaw<BR>
allow=ulaw<BR> allow=gsm<BR>
rtptimeout=60<BR> dtmfmode=rfc2833<BR>
h323id=PABX</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>I have the Cisco document "Understanding H.323 Gatekeepers" available
here:</DIV>
<DIV> </DIV>
<DIV> <A
href="http://www.cisco.com/warp/public/788/voip/understand-gatekeepers.html">http://www.cisco.com/warp/public/788/voip/understand-gatekeepers.html</A></DIV>
<DIV> </DIV>
<DIV>
<DIV>While there is a diagram (top of page 10) in the Cisco document which
appears to show exactly what I want to make there's scant information on how to
configure it and hence its limited help with what I am trying to do, namely
gateway between two different H.323 gateways in a single zone and route calls
between the two gateways - for example:</DIV></DIV>
<DIV><BR> Route
Where
Description</DIV>
<DIV> </DIV>
<DIV>
817.... TETRA
to mobiles/portables on the Damm TETRA
system<BR> 8......
PABX to
numbers in the rest of my number plan<BR>
0.
PABX through
the PABX on to the PSTN<BR>
9..
PABX through
the PABX to emergency 911/999</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>I can see how this be acheived if I had two Gatekeepers and two
zones, say one called "tetra" and one called "asterisk" by using zone prefixes
and "zone remote" to route between them and putting one of the
gateways on each of the Gatekeepers - but this appears to be over-the-top for
what I want, ie. two gateways on the same Gatekeeper at the same site, in the
same zone, routing calls between them...</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>Can anyone give me a clue where to go next with this?</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>Mike</DIV>
<DIV> </DIV>
<DIV></FONT> </DIV></BODY></HTML>