What is MCA
• Missed Call Alert system
• Notify subscriber who has just return to network
about missed calls while he was unavailable
• It is can also be useful to notify the caller that
called party is now reachable. We call it
• MCA is one of killing Value added Services, beside
RingBackTone, SMS, which generate most VAS
revenue for Mobile network.
2 ways to develop MCA service
• (1)Call Forwarding based (CFb). The system
will receive call forwarding on B party
unavailable, record the missed calls then
• (2) Camel Monitor based (CMb). The system
will do non-intrusive monitoring the signaling
between gsmSSF and gsmSCF to detect missed
Camel Monitor based solution
• It is best for network with almost Prepaid
subscriber or the gsmSCF can also handle call
procedure for Postpaid.
• Like the CFb, it is still required modules for
detecting B party to be online, sending SMS.
• The most advantage of CMb is it does not
require new SS7Node to be installed, CMb is
fast to detect Missed call and also can monitor
all normal calls.
The CMb Model
• Call Monitor is in charge of collecting missed call
• In Camel, TD50 and 51 used for Missed Call (this
may be variant in mobile networks)
Span ports or live tapping
• Can monitor both legacy SS7 and SS7 over IP
• The SS7analyzer engine inside CallMonitor, we
call it Netmon.
• You will need CallMonitor to develop MCA,
and Netmon for CallMonitor
• The Network Monitor module, used to decode
SS7 message collected from live tapping or SPAN
• It is very fast, since it was developed in C++
language, for Unix based system and almost
activities are C pointer movement based. No
copying philosophy is applied.
• It support traffic based on M2UA, M3UA.
• Supported Stack: sccp, tcap, gsmmap and Camel
• Only Data is filtered, other signaling message will
be drop to increase performance. I.e on M3ua
layer, only Data with SCCP payload is retrieved, in
Sccp layer, only UDT (and xUDT) will be retrieved.
• Sccp Reassemble is supported
• Multiple Tcap Component portions is supported.
• Performance: about 8000 Ip frames/second on a
MacbookPro 2.4Ghz Duo core, 4GbRam, Debian
Netmon Decoding status
Multiple chunks supported
Call related message
messages will soon
• Compliant with: itut-Sccp (Q773, Q775), Itut-
Tcap (Q.713), GsmMap (gsm 09.02) and Camel
• At present, only Call related messages are
supported, i.e: Initital DP, requestBCSMReport,
eventBCSMReport, ApplyCharging, applyChargingReport,
• GPRS related message will soon be supported
To use Netmon
• Dedicate a file captured with Sigtran data in
• We will check for compatibility, customize
Netmon if necessary, the give you binary
• Decoding result will be written to a text file in
nice format. Your system can read the text file
for further processing.
• Information include: Sccp, Tcap, Cap data
To own Netmon
• Get full source with cmake ready.
• Customize netmon to redirect decoding result
to a core logic via networking for processing.
• Just email firstname.lastname@example.org to
• You can visit scansource to see Dialogic price
for Sigtran Monitor, only support to sccp