The SS7 protocol stack is similar to the Open System Interconnection or known as the OSI model.  However, there are only four levels are considered to be similar with the OSI layers.  The SS7 protocol stacks are identified at the Message Transfer Part (MTP) level 1, level 2, level 3, and the top level.  These are the same as the physical layer, data link layer, network layer, and the application layer.  The top level consists of TUP, TCAP, ISUP, and SSCP; each section of this level is important to the protocol stack.  The Message Transfer Part (MTP) level 1 is defined in the physical and electrical characteristics in providing the signaling; which include the E-1 network which has 2048 kb/s with providing 30 voice channels with a synchronizing channel and a common signal channel, and the DS-1 network has 1544 kb/s with providing 24 voice channels, or 23 voice channels and one common signaling channel.  The message Transfer Part (MTP) level 2 provides the accurate data transmission during the call including the call initiation and termination.  In this transmission, the layer implements sequence validation, error protection, and flow control.  If the error is detected during the signal transmission, the message will be retransmitted.  The MTP level 3 offers the routing function between the signal points, which avoids failure connection transmission when the signals are congested.  The ISDN User Part distinct the protocol is initiating the call, managing the call, and terminating the circuits to end the call.  Perhaps, if the call is made within the switch system network, it does not require using ISUP signaling.  The Telephone User Part is simpler than ISUP, example is no caller ID; however, TUP is used more in handling analog circuits.  Certain parts of the world still use TUP for setting up the call and terminating the call processes.  The majority networks in the globe replaced TUP by the ISUP, especially in the European Union Nations and North America.  The Signaling Connection Control Part (SSCP); is a connection-oriented and connectionless network.  Its functions are controlling the toll free number, calling card number, and customer identification number; therefore, it is easy to track the billing usage.  The SSCP would translate these numbers into the subsystem number to identify the destination signal to the Transaction Capabilities Application Part.  The TCAP provides information between non-circuits data across the SS7 by using SSCP services.  Its functions are authentication, personal identification number validation, equipment identification, and roaming services.

The Signaling Links is known to transmit both directions between 56 to 64 kilobits per section.  These signals are transmitted on an out-of-band channel, separate from voice channel because they are Intelligent Network to separate these two types of signals.  It also prevents fraudulent network service usage, such as stealing network for commercial purposes and reselling the calling cards.  The Signaling Point are unique because the point codes.  Point codes are addresses in the SS7 network and identify the destination and source.  The Signaling points use routing table rule for the path of individual messages.  There are three types of Signaling Point in SS7:  Service Switching Point (SSP), Signal Transfer Point (STP), and Service Control Point (SCP).  The SSP’s are performing as switches that initiating and terminating the call.  The Signaling messages are being setup, manage and terminate in the voice circuits for every single call.  The STP provides signaling points by routing new message for every incoming message to the specific SSP.  It also acts as a firewall to ensure exchanged manages are secured.  The SCPs provide the configuration service in the event of signaling failure, or for special services like “800” numbers.  If the transmission failed, the SCP re-route the signaling messages to a different base links, or remove the call to a different destination for 800 services.

There are six different Signaling Link types; these are from A to F, in respect to the SS7 protocol.  The A link is connecting between the signaling end points for message from or to the destination sources.  The B link is connecting between STP’s to provide signaling message transmission.  The C link is connecting between STP’s; however, it pairs up the signal point for reliability if a link fails.  The D link provides secondary connection in STP’s unless there is a problem with the primary, and then the D link temporarily replaces the B link connection.  The E link is connecting between SSP and STP, it is an alternating path in the event that the A link is not reachable.  The F link is connecting between the two end points likes the A link.  Normally, it is not used in STPs, unless there is a problem with STP’s, and not being used; therefore, the F link is replaced for straight connection.

The typical call process in the SS7 involves two phone switches; one is as a sender “A” and the other one is a recipient “B.”   During the initial calling process, the sender signaling message goes through a switch “A” to determine the destination number and linking itself to the switch “B.”   The trunk voice routing would be setup in response to address message to define the destination source.  Therefore, from the switch “A” routing the message to the switch “B,” and determine whether the call is signaling or busy due to the recipient engaged in calls.  Once the setup is done, the switch “B” would start to formulate the answer message to identify the connection.  The answer message indicates if the destination reason has gone “off-hook.”  This leads to a voice channel connection.  If the sender hangs up the phone first, then the switch “A” would generate a release message (REL) to the recipient or switch “B.”  The opposite happens when a user hangs up.  In either this case, the other party receives a release complete message (RLC).

In brief the SS7 is a global standard protocol defined by the ITU for telecommunication, and especially for wireless networks.  It consists of 4 different levels and similar to the Open System Interconnection Model.  It has three different signaling Point types and sign different link types.

References:

. Bates, Regis J. “Broadband Telecommunications Handbook.” McGraw-Hill Companies Inc, United States. 2002

. Heine, Gunnar.  “GSM Networks: Protocols, Terminology, and Implementation.” Artech House Inc., Norwood, MA. 1999.

. “SS7 Tutorial” International Engineering Consortium.  November 27, 2008.  <http://www.iec.org/online/tutorials/ss7>

The developed country Governments should consider carefully in make any decision to deal with foreign investment and trades.  Perhaps, they should use their past experiences to assist the developing countries, and possible considering the future outcome not the present.  In contrast developing countries should be modernized to accept foreign relations and adopt capitalism.  In the recent report shows most of developing countries are usually historical Socialist or Monarchy type of Government.  Obviously, there is nothing wrong with being non-capitalism, but they should to choose what had been proven that work best for the economies.  Obviously, some studies show there are downturns of globalization with negative impacts.  In order to prevent the future negative impact and financial crisis, the Government should analysis the weakness that cause problem.

Before the World Trade Center was attacked by Terrorists in September 2001, the globalization was the main subject for discussion in increasingly international economies.  It plays the major role in intellectual and political divides; in order to be well developed nations must undergo through many phrases, and many positive and negative impacts as the results.  There is always tough decision on Government because some problems arise from globalization such as job loss, immigration issues, national boarder protection, and etc.  Sometimes private sectors have problem making decision due to economies downturn.  But mostly the trend in decision making is always to the Government.   In the recent interview President Obama’s Senior Economic Advisor, Mr. Larry Summers by Harold Myerson; who stated, ‘”those who, just as in the 1930s, tried to learn the lesson that market capitalism didn’t work and needed to be replaced with an entirely different model.” He believes in the past capitalism did not work well as it should; therefore, suggesting the Government should take different approaches on capitalism to aim for positive result.  That could be a tough decision on Politian enough because the Government controls regulations and foreign policies.  Since September 11, 2001 incident with terrorism, many developed countries are protested and debated against globalization.  However, the debated issues are much stronger due to the essential of how economies are structured and especially individual governments deal with each others.  In the recent years, it has been increasing interaction of Governmental agencies in globalization because of their federal economic systems.  Moreover, the developed countries should make the market leaning forward to world economies, or maybe at least some essential aspect.  Mr. Alan Greenspan of Bank for International Settlements believes that developing countries must strive to have more globalization.

The globalization could be beneficial depends on how individual national government dealing with international relations with other countries.  It gives opportunities for developing countries to improve benefit consumers and proficient producers, but it requires more challenges.  Furthermore, providing free trade between nations and link countries to peace likes United Nations.  In modern economies, marketing and trading play major key in national wealth.  Therefore, globalization is the opening for countries to access large markets, and beneficial capital flows.  Perhaps increasing the imports and exports of goods and services would be the factor of its benefits.   In other words, more investment would boost better living standards within the developing country, meaning it is force for long term economy stabilities.  For certain countries specialize at different products, for example, Japan is known well in the electronic and automobile productions, China is known for cheap labor in goods, so India in customer services.  Per Mr. Palmer’s research shows free trade is the greatest path to eliminated child labor.  “Around the world approximately 250 million children labor,” this number has been dropped dramatically when globalization is implemented.  It also improve their education opportunities because with better living condition would be an open door.

Although globalization brings many benefits to the world, but always there are people fears of international financial market crises; besides, the benefits for invested countries would be unbalanced.  In this case, the Government would be the central regulation for limited trades leading to imports issue to become dangerous.  This is possible to become more broken economic systems around the world.   Last year, the world economies were suddenly shifted to unexpected direction, many countries poverty had risen up to high percentages.  The national average income had dropped across the developing countries include:  17% in Indonesia, 40% in China, 32% in South Africa, 40% in China, 40% in India, 24% in Argentina, and etc.  In the article, “Why Globalization Is in Trouble,” by Mr. Branko Milanovic, he emphasizes that more developed countries fear with globalization due to job loss because of outsourcing to developing countries.  Today with modern technologies have shifted the jobs outsourcing to low-wage countries, which give the countries like United States and Canada financial crisis.  Maybe the benefit of job outsourcing would help the price on production cheaper for consumers; however, imagine million jobs are sent to over-sea that means million people lose their jobs.   Another fear is increasing immigration, which possible lead to culture intensity issue.  The immigration has been the most important agenda in the United States for the past decade; especially during the recent presidential election.  Whether the there are methods to control immigration problem in this country.  Both job loss and immigration problems are brought by globalization, which is harmful to developed countries.

In order to minimize the negative impact on globalization, every country should attempt to stop terrorism.   Mr. Alan Greenspan’s research shows terrorism is number one concern in globalization on economy downturns. “Terrorism poses a challenge to the remarkable record of globalization.  A global society reflects an ever more open economic environment…” There are several ways that the Government and Central Bank can do to minimize the negative impact on globalization such as changing policies on foreign affairs, trading, or lowering interest rates.

In brief, globalization is the central key to world economies; however, not every single participated country would be beneficial.  Some countries might suffer serious crisis due to terrorism, job loss, market downturns, and even national debts.  In the opposite side, new age of globalization has brought to high standard and most of developing countries are up to the speed.  Improving the marketing trades and living condition standard are most influences.

REFERENCES

• Faiola, Anthony. “A Global Retreat As Economies Dry Up.”  Washington Post, March 5, 2009.
• Gjelten, Tom. “Economic Crisis Poses Threat to Global Stability.” National Public Radio, February 18, 2009.
• Greenspan, Alan. “Globalization.” Bank for International Settlements.  October 24, 2001.  Retrieved on July 5, 2009. URL: http://www.bis.org/
• Milanovic, Branko. “Developing Countries Worse Off Than Once Thought.” Yale Global Online. Carnegie Endowment. February 11, 2008.  URL: http://www.carnegieendowment.org
• Milanovic, Branko.”Why Globalization Is in Trouble.” Yale Global Online. Carnegie Endowment. August 29, 2006. URL: http://www.carnegieendowment.org
• Palmer, Tom G. “Globalization is Great.”  Cato Institute. October 2002. Retrieved on July 7, 2009.
• Beneficial trend: The globalization of well-being”. Growth Strategies. FindArticles.com. 02 Aug, 2009. http://findarticles.com/p/articles/mi_qa3908/is_200301/ai_n9208283/