TD 92326GB
2009-03-10 / Ver. E
Installation and Operation Manual
VoIP Gateway
142
20
Different Usage of the VoIP Gateway
20.1 Dealing with the various ISDN address types
Call numbers are always treated internally by the VoIP Gateway as unknown type of
number. In ISDN however, there are various types of call numbers (see the table below)
with the effect that call numbers are only ever interpreted in combination with their
number types.
On an exchange line in for example Germany, a call number
0
711654321 with the type of
number “unknown” corresponds to the call number 711654321 with the type of number
“national”. This is due to the fact that in Germany the code for national numbers is
0
.
On the other hand the call number 41551234 with the number type “unknown” refers to
a connection within one's own local network, whereas the same number 41551234 with
a number type “international” refers to a connection in the local network of Pfäffikon in
Switzerland.
The call number type “unknown” therefore has to be standardized in order to evaluate
call numbers within the VoIP Gateway. This can be done with the help of entries in the
CGPN (calling party number) map and CDPN (called party number) map, which can be
defined both on the ISDN interfaces, and in the individual VoIP interface definitions.
Number types:
The following map entries for the calling number are included by default in all ISDN
interfaces and gatekeeper interfaces:
Name Description Typical
use Abbreviation
a
a.In the CGPN/CDPN mappings
Code
b
b.Equivalent codes for outgoing calls in Germany
Unknown
Unspecified
Number called in
outgoing call.
u
Subscriber
Call number in local
network.
Number called in
incoming call.
s
National
Call number with area
code
Calling number
from home
country.
n 0
International Call
number
with
country code and area
code.
Calling number
from abroad.
i 00
Abbreviated Unusual
a
Network
specific
Unusual x
Type Number
type
Number
prefix
Replaced
number
prefix
Use
Incoming
calling
number
National Blank
0
Places
the
discriminating
digit 0 in front of national
calling numbers
