E.3 Examples of echo control procedure

09.123GPPApplication of ISDN User Part (ISUP) Version 2 for the Integrated Services Digital Network (ISDN) - Public Land Mobile Network (PLMN) signalling interfacePart 1: Protocol specificationTS

The following additional notations are used in figures E.1 to E.13:

G Gateway in the fixed network

(o.i) outgoing half echo control device included

(o.ni) outgoing half echo control device not included

(i.i) incoming half echo control device included

(i.ni) incoming half echo control device not included

(*) echo control device "reserved"

* echo control device enabled

x echo control device disabled

i incoming half echo control device

o outgoing half echo control device

E.3.1 Call from a mobile station to a mobile station via the fixed network

Figure E.1

E.3.2 Call from a mobile station to fixed network with no echo control device

Figure E.2

E.3.3 Call from a mobile station to fixed network with echo control device

Figure E.3

E.3.4 Call from fixed network with no echo control device to a mobile station roaming in a PLMN of another country

Figure E.4

E.3.5 Call from fixed network with echo control device to a mobile station roaming in a PLMN of another country

Figure E.5

E.3.6 Call from fixed network with no echo control device to a mobile station

Figure E.6

E.3.7 Call from fixed network with echo control device to a mobile station

Figure E.7

E.3.8 Call forwarded by the VMSC

Figure E.8

E.3.9 Call forwarded by the VMSC to the fixed network with no echo control device

Figure E.9

E.3.10 Call with no outgoing echo control device included in a preceding exchange forwarded by the VMSC to the fixed network with no echo control device in the terminating network. The VMSC knows that an outgoing half echo control device is not necessary

Figure E.10

E.3.11 Call with no outgoing echo control device included in a preceding exchange forwarded by the VMSC to the fixed network with echo control device in the terminating network. The VMSC knows that an outgoing half echo control device is not necessary

Figure E.11

E.3.12 Call with no outgoing echo control device included in a preceding exchange forwarded by the VMSC to the fixed network with no echo control device in the terminating network. The VMSC knows that an outgoing half echo control device is necessary

Figure E.12

E.3.13 Call with no outgoing echo control device included in a preceding exchange forwarded by the VMSC to the fixed network with echo control device in the terminating network. The VMSC knows that an outgoing half echo control device is necessary

Figure E.13