TABLE OF CONTENTS What is wrong with the setup for the roaming in the GSM (in Africa) shown in Figure 16.3: the danger of using international point codes. A group of mobile operators uses a private STP to concentrate the international signaling traffic of its members (several operators in Africa, Asia, and so on). VSAT links exist between the gateway of these mobile operators and the private STP. All have an international point code.
The private STP operator has a direct connection with one of the main SS7 carriers, which offers SCCP service as well as MTP transit traffic. GSM Africa has set up a number of roaming agreements in the past weeks.
The private STP has received a big invoice (for the MSU traffic) sent to the IGP. It has set up an analyzer on the satellite link between the STP and GSM Africa, which shows that many SSTs have been sent from GSM Africa to various international point codes without response. Answer these questions:
What is wrong (but works) with the setup for the roaming of GSM Africa?
What should the private STP operator do to prevent any such occurrence in the future? What should it do to switch from the present configuration to a better one without disrupting the roaming agreement of GSM Africa?
Why is there no response to the SST?
Should the SST on this satellite link be enabled?
