
Figure 3.4 Model of a Laser transceiver used in an FSO system
3.4 Channel characteristics in FSO system
3.4.1. Types of attenuation in FSO transmission medium
The transmission channel of the FSO system involves the transmission, absorption and scattering of light by the earth's atmosphere. The atmosphere interacts with light depending on the composition of the air, which under normal conditions consists of various types of gas molecules and suspended particles. The interaction produces various optical phenomena: selective absorption, scattering, and flickering of the received light.
Selective absorption : of radiation transmitted in light wavelengths is created by interactions of photons and molecules, atoms (H 2 O, CO 2 , N 2 , O 2 , H 2 , O 3 …). This leads to the disappearance of transmitted photons, signal attenuation and increase in ambient temperature. This phenomenon depends on the composition of the air and the wavelength of the light used. There are wavelength regions where the transmission is almost transparent (no absorption) called frequency windows.

Figure 3.5 Environmental impact on FSO line
Scattering : the air environment is the result of partial interaction of light and elements (dust, water particles in the air) in the transmission medium. It only changes the radiation direction of the interacting component without changing the wavelength. Scattering occurs when the size of particles in the air is similar to the wavelength of the transmitted light. And in real conditions, it is mainly caused by fog and drizzle.
Flicker phenomenon : in FSO is the change of signal under the influence of temperature change inside the transmission medium, the random distribution of air layers on the transmission line is created. These layers have variable distance (10cm - 1km) and different temperatures, creating different refractive coefficients which are the cause of scattering, multi-path, and angle of incidence change. The received signal changes rapidly with a frequency range of 0.01 - 200 Hz. The changing wave front creates convergence and divergence of the light beam.
In addition, other impacts also greatly affect the transmission line such as obstacles arising during use: growing trees, flying creatures, movement of buildings or towers installing equipment, ground vibrations that deflect light rays. These types of occurrence are very low and we can also eliminate them.
Summary diagram of environmental impact on FSO system:
The influence of the atmosphere on the propagation of light fields
Signal degradation effects
Effect of reflection coefficient
Random air turbulence changes the reflection coefficient.
Light loss, due to slow change of reflection coefficients
Scattering
+ Rayleigh scattering (by electron resonance)
+ Mie scattering (due to airborne particles)
Absorb
+ Absorption lines of gas molecules
+ Continuous absorption;
+ Absorbed by solid and liquid elements.
Attenuation in space
Wavefront distortion
Expand the light beam
Flicker
Change the angle of incidence
3.4.2 Effect of atmospheric changes on signal quality
The change in the properties of the air causes a spatial and temporal variation in the signal intensity at the receiver. The reason is that this change causes the refractive index to change and the air acts like a lens that deflects the beam from the main direction to the receiver. The time of this change is the time the beam is transmitted through space and it depends on the wind speed. In practice, if the fluctuations are weak, the signal intensity distribution function is proportional to the logarithmic function. For space optics using horizontal propagation, this change is stronger, so the received intensity distribution function follows an exponential law.
The parameter commonly used to measure air change rate is the structural parameter.
refractive index
. It is directly related to wind speed. The change of
can be used to predict the change in signal strength at the receiver.
(3.2)



Where:
is the variance of the signal intensity change. is the refractive structure parameter ( .
k is the wave propagation constant (rad/m). L is the distance (m).
From the expression we see:
The air change intensity is inversely proportional to the wavelength used (a system operating at 780 nm has about a two-fold change at 1550 nm).
The effect of change is proportional to the distance.
The effect of the change is illustrated in Figure 3.6. The figure shows the receiver mouth with randomly distributed black and white spots. The spot size is proportional to (λR) 1/2 .
At long wavelengths the speckle is larger at the receiver mouth. This is not good for the system operation because there are few speckles at the receiver mouth. If the receiver mouth receives only one spot, the transmitter is required to increase the power to ensure the BER when the spot is a black spot.
Size is proportional to the square root of distance. Longer distances adversely affect the system.

Figure 3.6 Spots and average mouth size
3.5 Factors affecting, evaluating and improving the quality of wireless optical lines
3.5.1 Parameters affecting the quality of the line
3.5.1.1 Transmission equation of the line

The transmission equation of the space optical system in simple form (ignoring transmitter optical efficiency, receiver noise, etc.):
(3.3)
In there:
is the receiver surface area (m 2 )
Div is the beam divergence angle (radians).

α is the air attenuation coefficient.
P transmit is the transmitter power (W).
exp(-α.Range) is the exponential function with base e of the product of the attenuation coefficient and the distance.
The received power is directly proportional to the transmitted power and the receiver area. Inversely proportional to the square of the product of the beam divergence angle and the transmission distance. Inversely proportional to the exponential function of the air attenuation coefficient and the distance.
Looking at the equation the variables that can be changed are: transmit power, receiver size, beam divergence angle and distance. The attenuation coefficient is not controllable, depends on external environmental conditions and can be independent of wavelength in a severely attenuated medium.
It is found that the received power depends greatly on the product of the attenuation coefficient and the distance. Figure 3.7 illustrates this.
This means that in bad weather conditions, even if the designer increases the transmit power, the receiver size, or installs a very narrow beam, the received power will not change. The only variable parameter is the distance, which must be short enough to ensure that the attenuation factor does not dominate the equation.

Figure 3.7 Received power depends on the product of attenuation coefficient and distance
The x-axis represents the distance R (m) of the line. The y-axis is the value of the multiplier

exp(-α.Range) (natural logarithmic function) and the multiplier in the expression
(3.3).
Through this section we see the great influence of the attenuation coefficient in the environment.
weather conditions in the transmission equation compared to other quantities. However, it is possible to achieve efficient, optimal, reliable and economical designs under these constraints.
3.5.1.2 Air attenuation
The parameter that affects the transmission quality is mainly air loss. Let us analyze the influence of this parameter.
The laser power attenuation through air is defined by the Beers-Lambert law:
In there:

is the transfer function at distance R. P(R) is the power at distance R. P(0) is the power at the source.
α is the attenuation coefficient (1/Km).
(3.4)
Common attenuation factors: dry air = 0.1 (0.43dB/Km), haze = 1 (4.3dB/Km) and fog = 10 (43dB/Km).
The attenuation coefficient is caused by the absorption and scattering of laser photons by gas molecules in the air. Since the wavelengths commonly chosen for use (785 nm, 850 nm, 1550 nm) are within the transmission window, the influence of the absorption coefficient is small compared to the total attenuation. Therefore, the influence of the attenuation coefficient caused by transmission line scattering is dominant.
The type of scattering is determined by the specific particle size relative to the transmission wavelength.
It is described by a dimension number called the dimension parameter α :

(3.5)
In which: r is the scattering particle radius,
λ is the laser wavelength.
Table 3.2 Radius of scattered particles in air and corresponding size parameters of laser wavelengths 785 nm and 1550 nm.
Type
Radius (µm) | Dimensional parameters α | ||
785 nm | 1550 nm | ||
Air molecules | 0.0001 | 0.0008 | 0.0004 |
Fog | 0.01 – 1 | 0.08 – 8 | 0.04 – 4 |
Steam | 1 – 20 | 8 – 160 | 4 – 80 |
Rain | 100 – 10000 | 800 – 80000 | 400 – 40000 |
Snow | 1000 – 5000 | 8000 – 40000 | 4000 – 20000 |
Hail | 5000 – 50000 | 40000 – 800000 | 20000 - 400000 |
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Pre-tax Profit of Bidv Tien Giang in the Period 2011-2015
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At that time, the Branch had to set aside a provision for credit risks, which reduced the Branch's income.
Chart 2.2. Pre-tax profit of BIDV Tien Giang in the period 2011-2015
Unit: Billion VND
140
120
100
80
60
40
20
0
63.3
80.34
89.29
110.08
131.99
2011 2012 2013 2014 2015
Profit before tax
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
However, through chart 2.2, it can be seen that BIDV Tien Giang's profit is still increasing continuously, and its operating efficiency is currently leaking. This is a contribution of non-credit services, and this service segment will be increasingly focused on growth by BIDV Tien Giang to ensure the highest profit safety because credit activities have many potential risks. At the same time, focusing on developing non-credit services is consistent with one of the contents of restructuring the financial activities of credit institutions in the project "Restructuring the system of credit institutions in the period 2011-2015" approved by the Prime Minister in Decision No. 254/QD-TTg dated March 1, 2012 [14]: "Gradually shifting the business model of commercial banks towards reducing dependence on credit activities and increasing income from non-credit services".
2.2. Current status of non-credit service development at BIDV Tien Giang.
2.2.1. BIDV Tien Giang has deployed the development of non-credit services in recent times.
Along with the development of the Head Office, BIDV Tien Giang's products and services are constantly improved and deployed in a diverse manner to ensure provision for many different customer groups in the area: individual customers, corporate customers, and financial institutions. Typical services are as follows: Payment services, treasury services, guarantee services, card services, trade finance, other services: Western Union, insurance commissions, consulting services, foreign exchange derivatives trading, e-banking services,...
2.2.1.1. Payment services:
In accordance with the Prime Minister's Project to promote non-cash payments in Vietnam [15], banks in Tien Giang province have continuously developed payment services to reduce customers' cash usage habits through card services and electronic banking services such as: salary payment through accounts, focusing on developing card acceptance points, developing multi-purpose cards, paying social insurance by transfer, paying bills through banks, etc.
Chart 2.3. Net income from payment services in the period 2011-2015
Unit: Million VND
6000
5000
4000
3000
2000
1000
0
3922 4065
4720 5084 5324
2011 2012 2013 2014 2015
Net income from payment services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Along with the technological development of the entire system, BIDV Tien Giang has a payment system with a fairly stable transaction processing speed, bringing many conveniences to customers. The results of observing chart 2.3 show that the income from payment services that the Branch has achieved has grown over the years but the speed is not high and the products are not outstanding compared to other banks. Domestic payment products such as: Online bill payment, electricity bills, water bills, insurance premiums, cable TV bills, telecommunications fees, airline tickets, etc. bring many conveniences to customers. Regarding international payment, this is an indispensable activity for foreign economic activities, BIDV Tien Giang is providing international payment methods for small enterprises producing agriculture, aquatic food and seafood that have credit relationships with banks in industrial parks in Tien Giang province such as: money transfer, collection, L/C payment.
2.2.1.2. Treasury services:
BIDV Tien Giang always focuses on ensuring treasury safety and currency security, always complies with legal regulations, and minimizes risks in operations such as: counting and collecting money from customers, receiving and delivering internal transactions, collecting from the State Bank (SBV) or other credit institutions, receiving ATM funds, bundling money, etc. BIDV Tien Giang's treasury service management department is always fully equipped with modern machinery and equipment such as: money transport vehicles, fire prevention tools, money counters, money detectors, magnifying glasses, etc. to ensure absolute safety in treasury operations, immediately identifying real and fake money and other risks that may affect people and assets of the bank and customers. In addition, implementing regulation 2480/QC dated October 28, 2008 between the State Bank of Tien Giang province and the Provincial Police on coordination in the fight against counterfeit money, in the 3-year review of implementation, BIDV Tien Giang discovered, seized and submitted to the State Bank of Tien Giang province 475 banknotes of various denominations and was commended by the Provincial Police and the State Bank of Tien Giang province [17].
Chart 2.4. Net income from treasury services in the period 2011-2015
Unit: Million VND
350
300
250
200
150
100
50
0
105 122
309 289 279
2011 2012 2013 2014 2015
Net income from treasury services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
However, as shown in Figure 2.4, income from treasury operations is not high and fluctuates. Specifically, in the period 2011-2013, net income increased and increased most sharply in 2013, then in the period 2013-2015, there was a downward trend. This fluctuation is due to the fact that fees collected from treasury services are often very low and can even be waived to attract customers to use other services.
2.2.1.3. Guarantee and trade finance services:
BIDV Tien Giang, thanks to the advantages of the province and the favorable location of the Branch, has continuously focused on developing income from guarantee services and trade finance.
Chart 2.5. Net income from guarantee and trade finance services in the period 2011-2015
Unit: Million VND
14000
12000
10000
8000
6000
4000
2000
0
5193 5695
2742 3420
8889
3992
11604 12206
5143 5312
2011 2012 2013 2014 2015
Net income from guarantee services Net income from Trade Finance
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Through chart 2.5, we can see that BIDV Tien Giang's income from guarantee services and trade finance has grown over the years. The reason is: Among BIDV Tien Giang's corporate customers, the construction industry is the industry with the highest proportion of customers after the trading industry, this is a group of customers with potential to develop guarantee services. The second group of customers is corporate customers in the fields of agricultural production, livestock and seafood processing with high import and export turnover in the area.
are the target of trade finance development. In addition, BIDV Tien Giang also focuses on continuously developing these customer groups to increase revenue for many other products and services in the future.
2.2.1.4. Card and POS services:
As a service that BIDV Tien Giang has recently developed strongly, it can be said that this is a very potential market and has the ability to develop even more strongly in the future. Card services with outstanding advantages such as fast payment time, wide payment range, quite safe, effective and suitable for the integration trend and the Project to promote non-cash payments in Vietnam. Cards have become a modern and popular payment tool. BIDV Tien Giang early identified that developing card services is to expand the market to people in society, create capital mobilized from card-opened accounts, contribute to diversifying banking activities, enhance the image of the bank, bring the BIDV Tien Giang brand to people as quickly and easily as possible. BIDV Tien Giang is currently providing card types such as: credit cards (BIDV MasterCard Platinum, BIDV Visa Gold Precious, BIDV Visa Manchester United, BIDV Visa Classic), international debit cards (BIDV Ready Card, BIDV Manu Debit Card), domestic debit cards (BIDV Harmony Card, BIDV eTrans Card, BIDV Moving Card, BIDV-Lingo Co-branded Card, BIDV-Co.opmart Co-branded Card). These cards can be paid via POS/EDC or on the ATM system. In addition, with debit cards, customers can not only withdraw money via ATMs but also perform utilities such as mobile top-up, online payment, money transfer,... through electronic banking services.
In order to attract customers with card services, BIDV Tien Giang has continuously increased the installation of ATMs. As of December 31, 2015, BIDV Tien Giang has 23 ATMs combined with 7 ATMs in the same system of BIDV My Tho, so the number of ATMs is quite large, especially in the center of My Tho City, but is not yet fully present in the districts. Basic services on ATMs such as withdrawing money, checking balances, printing short statements,... BIDV ATMs accept cards from banks in the system.
Banknetvn and Smartlink, cards branded by international card organizations Union Pay (CUP), VISA, MasterCard and cards of banks in the Asian Payment Network. From here, cardholders can make bill payments for themselves or others at ATMs, by simply entering the subscriber number or customer code, booking code that service providers notify and make bill payments.
Chart 2.6. Net income from card services in the period 2011-2015
Unit: Million VND
3500
3000
2500
2000
1500
1000
500
0
687
1023
1547
2267
3104
2011 2012 2013 2014 2015
Net income from card services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Through chart 2.6, it can be seen that BIDV Tien Giang's card service income is constantly growing because the Branch focuses on developing businesses operating in industrial parks, which are the source of customers for salary payment products, ATMs, BSMS. Specifically, there are companies such as Freeview, Quang Viet, Dai Thanh, which are businesses with a large number of card openings at the Branch, contributing to the increase in card service fees [25].
Table 2.6. Number of ATMs and POS machines in 2015 of some banks in Tien Giang area.
Unit: Machine
STT
Bank name
Number of ATMs
Cumulative number of ATM cards
POS machine
1
BIDV Tien Giang
23
97,095
22
2
BIDV My Tho
7
21,325
0
3
Agribank Tien Giang
29
115,743
77
4
Vietinbank Tien Giang
16
100,052
54
5
Dong A Tien Giang
26
97,536
11
6
Sacombank Tien Giang
24
88,513
27
7
Vietcombank Tien Giang
15
61,607
96
8
Vietinbank - Tay Tien Giang Branch
6
46,042
38
(Source: 2015 Banking Activity Data Report of the General and Internal Control Department of the Provincial State Bank [21])
Through table 2.6, the author finds that the number of ATMs of BIDV Tien Giang is not much, ranking fourth after Agribank Tien Giang, Dong A Tien Giang, Sacombank Tien Giang. The number of POS machines of BIDV Tien Giang is very small, only higher than Dong A Tien Giang and BIDV My Tho in the initial stages of merging the BIDV system. Besides, BIDV Tien Giang has a high number of cards increasing over the years (table 2.7) but the cumulative number of cards issued up to December 31, 2015 is still relatively low compared to Agribank, Vietcombank, Dong A (table 2.6).
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Model system to assess the suitability of Vietnam's population-economic development process - 21 -
Research Model to Evaluate the Effectiveness of the Ksnb System at Provincial Radio and Television Stations in Vietnam -
Building a Research Model on Factors Affecting the Effectiveness of Internal Control System in Social Insurance Collection -
Linkage Model of a Typical Qtdnd System 1.2.2.2- Linkage Development Support Department
Rayleigh scattering occurs when air particles are smaller than the laser wavelength (785 nm and 1550 nm) due to gas molecules (Cox, Nox…) in the air. The attenuation coefficient varies according to λ -4 . The influence of this scattering on the total attenuation coefficient is very small.
As the particle size approaches the laser wavelength, the radiation of the particle scatters in the direction opposite to the propagation direction. This scattering is Mie scattering caused by small fog particles. With Mie scattering, the wavelength exponent in relation to the attenuation coefficient changes from -1.6 to 0.

Figure 3.8 Scattering particle size parameters
Figure 3.8 shows the scattering particle size parameters in Table 3.2 at laser wavelengths of 785nm and 1550nm for Rayleigh, Mie and non-selective scattering, respectively.
The third common scattering occurs when the particle size is larger than the wavelength. For size parameters greater than 50, this scattering is called geometric or non-selective scattering (since there is no dependence of the attenuation coefficient on wavelength and the exponent of the wavelength in the attenuation coefficient is zero). These scattering particles are large enough that the angle of the scattered radiation can be described by geometric optics. Falling rain, snow, and heavy fog will cause this scattering.
The amount of air scattering for short communication links is either wavelength dependent (Mie scattering) or wavelength independent (geometric or non-selective scattering).
3.5.2 Parameters for evaluating the quality of the line
3.5.2.1 Route usability
Line usability is a key factor to consider when installing the system.
Affected by many factors:
Equipment reliability. This factor can be ensured by selection, calculation, and design.
The air attenuation statistics are unknown. They are collected through specialized equipment such as visibility and rainfall meters. These devices are often installed with the space optical system. From the data of these devices, we can calculate the air attenuation coefficient. And we can accurately estimate the usability of the line over a transmission distance.
3.5.2.2 Bit error rate BER and data rate over transmission distance
We consider the effect of fog based on the visibility range. The distant building is about 300m away from the photographed building. The left image shows dry air, the attenuation coefficient is about 6.5dB/Km (2000m visibility) measured by a nephelometer (turbidity measuring device) mounted on the camera. During the fog, the attenuation coefficient is about 150dB/Km (113m visibility) shown in the middle image, the building is still visible. In the right image, the attenuation coefficient is 225dB/Km (75m visibility) and the building is completely lost.

![Pre-tax Profit of Bidv Tien Giang in the Period 2011-2015
zt2i3t4l5ee
zt2a3gsnon-credit services, joint stock commercial bank
zt2a3ge
zc2o3n4t5e6n7ts
At that time, the Branch had to set aside a provision for credit risks, which reduced the Branchs income.
Chart 2.2. Pre-tax profit of BIDV Tien Giang in the period 2011-2015
Unit: Billion VND
140
120
100
80
60
40
20
0
63.3
80.34
89.29
110.08
131.99
2011 2012 2013 2014 2015
Profit before tax
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
However, through chart 2.2, it can be seen that BIDV Tien Giangs profit is still increasing continuously, and its operating efficiency is currently leaking. This is a contribution of non-credit services, and this service segment will be increasingly focused on growth by BIDV Tien Giang to ensure the highest profit safety because credit activities have many potential risks. At the same time, focusing on developing non-credit services is consistent with one of the contents of restructuring the financial activities of credit institutions in the project Restructuring the system of credit institutions in the period 2011-2015 approved by the Prime Minister in Decision No. 254/QD-TTg dated March 1, 2012 [14]: Gradually shifting the business model of commercial banks towards reducing dependence on credit activities and increasing income from non-credit services.
2.2. Current status of non-credit service development at BIDV Tien Giang.
2.2.1. BIDV Tien Giang has deployed the development of non-credit services in recent times.
Along with the development of the Head Office, BIDV Tien Giangs products and services are constantly improved and deployed in a diverse manner to ensure provision for many different customer groups in the area: individual customers, corporate customers, and financial institutions. Typical services are as follows: Payment services, treasury services, guarantee services, card services, trade finance, other services: Western Union, insurance commissions, consulting services, foreign exchange derivatives trading, e-banking services,...
2.2.1.1. Payment services:
In accordance with the Prime Ministers Project to promote non-cash payments in Vietnam [15], banks in Tien Giang province have continuously developed payment services to reduce customers cash usage habits through card services and electronic banking services such as: salary payment through accounts, focusing on developing card acceptance points, developing multi-purpose cards, paying social insurance by transfer, paying bills through banks, etc.
Chart 2.3. Net income from payment services in the period 2011-2015
Unit: Million VND
6000
5000
4000
3000
2000
1000
0
3922 4065
4720 5084 5324
2011 2012 2013 2014 2015
Net income from payment services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Along with the technological development of the entire system, BIDV Tien Giang has a payment system with a fairly stable transaction processing speed, bringing many conveniences to customers. The results of observing chart 2.3 show that the income from payment services that the Branch has achieved has grown over the years but the speed is not high and the products are not outstanding compared to other banks. Domestic payment products such as: Online bill payment, electricity bills, water bills, insurance premiums, cable TV bills, telecommunications fees, airline tickets, etc. bring many conveniences to customers. Regarding international payment, this is an indispensable activity for foreign economic activities, BIDV Tien Giang is providing international payment methods for small enterprises producing agriculture, aquatic food and seafood that have credit relationships with banks in industrial parks in Tien Giang province such as: money transfer, collection, L/C payment.
2.2.1.2. Treasury services:
BIDV Tien Giang always focuses on ensuring treasury safety and currency security, always complies with legal regulations, and minimizes risks in operations such as: counting and collecting money from customers, receiving and delivering internal transactions, collecting from the State Bank (SBV) or other credit institutions, receiving ATM funds, bundling money, etc. BIDV Tien Giangs treasury service management department is always fully equipped with modern machinery and equipment such as: money transport vehicles, fire prevention tools, money counters, money detectors, magnifying glasses, etc. to ensure absolute safety in treasury operations, immediately identifying real and fake money and other risks that may affect people and assets of the bank and customers. In addition, implementing regulation 2480/QC dated October 28, 2008 between the State Bank of Tien Giang province and the Provincial Police on coordination in the fight against counterfeit money, in the 3-year review of implementation, BIDV Tien Giang discovered, seized and submitted to the State Bank of Tien Giang province 475 banknotes of various denominations and was commended by the Provincial Police and the State Bank of Tien Giang province [17].
Chart 2.4. Net income from treasury services in the period 2011-2015
Unit: Million VND
350
300
250
200
150
100
50
0
105 122
309 289 279
2011 2012 2013 2014 2015
Net income from treasury services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
However, as shown in Figure 2.4, income from treasury operations is not high and fluctuates. Specifically, in the period 2011-2013, net income increased and increased most sharply in 2013, then in the period 2013-2015, there was a downward trend. This fluctuation is due to the fact that fees collected from treasury services are often very low and can even be waived to attract customers to use other services.
2.2.1.3. Guarantee and trade finance services:
BIDV Tien Giang, thanks to the advantages of the province and the favorable location of the Branch, has continuously focused on developing income from guarantee services and trade finance.
Chart 2.5. Net income from guarantee and trade finance services in the period 2011-2015
Unit: Million VND
14000
12000
10000
8000
6000
4000
2000
0
5193 5695
2742 3420
8889
3992
11604 12206
5143 5312
2011 2012 2013 2014 2015
Net income from guarantee services Net income from Trade Finance
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Through chart 2.5, we can see that BIDV Tien Giangs income from guarantee services and trade finance has grown over the years. The reason is: Among BIDV Tien Giangs corporate customers, the construction industry is the industry with the highest proportion of customers after the trading industry, this is a group of customers with potential to develop guarantee services. The second group of customers is corporate customers in the fields of agricultural production, livestock and seafood processing with high import and export turnover in the area.
are the target of trade finance development. In addition, BIDV Tien Giang also focuses on continuously developing these customer groups to increase revenue for many other products and services in the future.
2.2.1.4. Card and POS services:
As a service that BIDV Tien Giang has recently developed strongly, it can be said that this is a very potential market and has the ability to develop even more strongly in the future. Card services with outstanding advantages such as fast payment time, wide payment range, quite safe, effective and suitable for the integration trend and the Project to promote non-cash payments in Vietnam. Cards have become a modern and popular payment tool. BIDV Tien Giang early identified that developing card services is to expand the market to people in society, create capital mobilized from card-opened accounts, contribute to diversifying banking activities, enhance the image of the bank, bring the BIDV Tien Giang brand to people as quickly and easily as possible. BIDV Tien Giang is currently providing card types such as: credit cards (BIDV MasterCard Platinum, BIDV Visa Gold Precious, BIDV Visa Manchester United, BIDV Visa Classic), international debit cards (BIDV Ready Card, BIDV Manu Debit Card), domestic debit cards (BIDV Harmony Card, BIDV eTrans Card, BIDV Moving Card, BIDV-Lingo Co-branded Card, BIDV-Co.opmart Co-branded Card). These cards can be paid via POS/EDC or on the ATM system. In addition, with debit cards, customers can not only withdraw money via ATMs but also perform utilities such as mobile top-up, online payment, money transfer,... through electronic banking services.
In order to attract customers with card services, BIDV Tien Giang has continuously increased the installation of ATMs. As of December 31, 2015, BIDV Tien Giang has 23 ATMs combined with 7 ATMs in the same system of BIDV My Tho, so the number of ATMs is quite large, especially in the center of My Tho City, but is not yet fully present in the districts. Basic services on ATMs such as withdrawing money, checking balances, printing short statements,... BIDV ATMs accept cards from banks in the system.
Banknetvn and Smartlink, cards branded by international card organizations Union Pay (CUP), VISA, MasterCard and cards of banks in the Asian Payment Network. From here, cardholders can make bill payments for themselves or others at ATMs, by simply entering the subscriber number or customer code, booking code that service providers notify and make bill payments.
Chart 2.6. Net income from card services in the period 2011-2015
Unit: Million VND
3500
3000
2500
2000
1500
1000
500
0
687
1023
1547
2267
3104
2011 2012 2013 2014 2015
Net income from card services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Through chart 2.6, it can be seen that BIDV Tien Giangs card service income is constantly growing because the Branch focuses on developing businesses operating in industrial parks, which are the source of customers for salary payment products, ATMs, BSMS. Specifically, there are companies such as Freeview, Quang Viet, Dai Thanh, which are businesses with a large number of card openings at the Branch, contributing to the increase in card service fees [25].
Table 2.6. Number of ATMs and POS machines in 2015 of some banks in Tien Giang area.
Unit: Machine
STT
Bank name
Number of ATMs
Cumulative number of ATM cards
POS machine
1
BIDV Tien Giang
23
97,095
22
2
BIDV My Tho
7
21,325
0
3
Agribank Tien Giang
29
115,743
77
4
Vietinbank Tien Giang
16
100,052
54
5
Dong A Tien Giang
26
97,536
11
6
Sacombank Tien Giang
24
88,513
27
7
Vietcombank Tien Giang
15
61,607
96
8
Vietinbank - Tay Tien Giang Branch
6
46,042
38
(Source: 2015 Banking Activity Data Report of the General and Internal Control Department of the Provincial State Bank [21])
Through table 2.6, the author finds that the number of ATMs of BIDV Tien Giang is not much, ranking fourth after Agribank Tien Giang, Dong A Tien Giang, Sacombank Tien Giang. The number of POS machines of BIDV Tien Giang is very small, only higher than Dong A Tien Giang and BIDV My Tho in the initial stages of merging the BIDV system. Besides, BIDV Tien Giang has a high number of cards increasing over the years (table 2.7) but the cumulative number of cards issued up to December 31, 2015 is still relatively low compared to Agribank, Vietcombank, Dong A (table 2.6).
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