Definition of VLAN:
VLAN is the abbreviation of English Virtual Local Area Network, also called virtual local area network. It is a technology that realizes virtual working group by dividing the devices in the local area network logically rather than physically into individual network segments. If you want to divide VLAN, you must purchase network equipment that supports VLAN function.
The role of VLAN division:
VLAN is proposed to solve the broadcast problem and security of Ethernet. Broadcast and unicast traffic within a VLAN will not be forwarded to other VLANs. Even if two computers on the same network segment are not in the same VLAN, their respective broadcast streams will not be forwarded to each other.
Dividing VLAN helps to control traffic, reduce equipment investment, simplify network management, and improve network security. Because VLAN isolates the broadcast storm and also isolates the communication between different VLANs, the communication between different VLANs must rely on routers or Layer 3 switches to achieve.
VLAN division method:
There are four ways to divide VLANs, each of which has its own strengths and weaknesses. When dividing a VLAN into a network, you must choose an appropriate dividing method according to the actual situation of the network.
1. Divide VLANs according to ports: Many network vendors use switch ports to divide VLAN members. As the name suggests, to divide VLAN based on ports is to define certain ports of the switch as a VLAN.
Dividing VLANs according to ports is the most commonly used method of dividing VLANs. The advantages of dividing VLANs according to ports are simple and clear, and management is also very convenient. The disadvantage is that maintenance is relatively cumbersome.
2. Divide VLAN according to MAC address: Each network card has a unique physical address in the world, namely MAC address. According to the MAC address of the network card, several computers can be divided into the same VLAN.
The biggest advantage of this method is that when the user's physical location moves, that is, when changing from one switch to another, the VLAN does not need to be reconfigured; the disadvantage is that when a VLAN is initialized, all users must be configured, which is a burden on the operator Heavier.
3. Divide VLANs according to the network layer: This method of dividing VLANs is based on the network layer address or protocol type of each host, not based on routing. Note: This VLAN division method is suitable for wide area networks and is basically not used in local area networks.
4. Divide VLANs according to IP multicast: IP multicast is actually a definition of VLAN, that is, a multicast group is considered to be a VLAN. This division method expands the VLAN to the wide area network, which is not suitable for the local area network, because the scale of the enterprise network has not yet reached such a large scale.
Obviously, all VLAN technologies are not completely suitable for a network. After having a comprehensive understanding of VLAN, we should be able to make an accurate judgment on whether we need to divide VLAN according to our network environment.
Choose the appropriate VLAN division mode
Many technical personnel only know that VLAN division can improve network transmission performance, but do not know that an unreasonable VLAN division mode will reduce network transmission performance. Due to the different environments of various networks, the VLAN division methods most suitable for their use are also different. Below, we will discuss in detail which VLAN division mode the enterprise network uses is more reasonable with an example.
Example corporate network: There are 43 clients in the network, of which 35 are desktop computers and 8 are laptops. The network traffic is not too large. Because the finance department has some sensitive data that do not want ordinary employees to see, in order to improve the security of the network, the network management decided to divide the network into VLANs to block the communication between ordinary employees and the PCs of the finance department employees.
Application requirements: From the above description, it can be seen that the company divides VLANs to improve security, and it is not the main purpose to improve network transmission performance. Due to the small number of client computers in this enterprise, notebooks are highly mobile. In daily office, managers usually need to move notebooks to conference rooms to meet the needs of mobile office. In this case, the mode of dividing VLANs based on ports is not suitable for the enterprise, and the most appropriate way to divide VLANs is based on MAC addresses.
Therefore, for enterprises, the most suitable VLAN division mode is to divide VLAN according to port and divide VLAN according to MAC address. For corporate networks where the number of clients is small and mobile offices are often required, dividing VLANs based on MAC addresses is the best division mode. For enterprise networks with a large number of clients and no mobile office, VLANs can be divided according to ports. In a word, choose an appropriate VLAN division mode according to network requirements.
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How far(long) the transmitter cover?
The transmission range depends on many factors. The true distance is based on the antenna installing height , antenna gain, using environment like building and other obstructions , sensitivity of the receiver, antenna of the receiver . Installing antenna more high and using in the countryside , the distance will much more far.
EXAMPLE 5W FM Transmitter use in the city and hometown:
I have a USA customer use 5W fm transmitter with GP antenna in his hometown ,and he test it with a car, it cover 10km(6.21mile).
I test the 5W fm transmitter with GP antenna in my hometown ,it cover about 2km(1.24mile).
I test the 5W fm transmitter with GP antenna in Guangzhou city ,it cover about only 300meter(984ft).
Below are the approximate range of different power FM Transmitters. ( The range is diameter )
0.1W ~ 5W FM Transmitter ：100M ~1KM
5W ~15W FM Ttransmitter : 1KM ~ 3KM
15W ~ 80W FM Transmitter : 3KM ~10KM
80W ~500W FM Transmitter : 10KM ~30KM
500W ~1000W FM Transmitter : 30KM ~ 50KM
1KW ~ 2KW FM Transmitter : 50KM ~100KM
2KW ~5KW FM Transmitter : 100KM ~150KM
5KW ~10KW FM Transmitter : 150KM ~200KM
How to contact us for the transmitter?
Call me +8618078869184 OR
Email me [email protected]
1.How far you want to cover in diameter ?
2.How tall of you tower ?
3.Where are you from ?
And we will give you more professional advice.
About Us
FMUSER.ORG is a system integration company focusing on RF wireless transmission / studio video audio equipment / streaming and data processing .We are providing everything from advice and consultancy through rack integration to installation, commissioning and training.
We offer FM Transmitter, Analog TV Transmitter, Digital TV transmitter, VHF UHF Transmitter, Antennas, Coaxial Cable Connectors, STL, On Air Processing, Broadcast Products for the Studio, RF Signal Monitoring, RDS Encoders, Audio Processors and Remote Site Control Units, IPTV Products, Video / Audio Encoder / Decoder, designed to meet the needs of both large international broadcast networks and small private stations alike.
Our solution has FM Radio Station / Analog TV Station / Digital TV Station / Audio Video Studio Equipment / Studio Transmitter Link / Transmitter Telemetry System / Hotel TV System / IPTV Live Broadcasting / Streaming Live Broadcast / Video Conference / CATV Broadcasting system.
We are using advanced technology products for all the systems, because we know the high reliability and high performance are so important for the system and solution . At the same time we also have to make sure our products system with a very reasonable price.
We have customers of public and commercial broadcasters, telecom operators and regulation authorities , and we also offer solution and products to many hundreds of smaller, local and community broadcasters .
FMUSER.ORG has been exporting more than 15 years and have clients all over the world. With 13 years experience in this field ,we have a professional team to solve customer's all kinds of problems. We dedicated in supplying the extremely reasonable pricing of professional products & services. Contact email : [email protected]
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Where is Fmuser ?
You can search this numbers " 23.127460034623816,113.33224654197693 " in google map , then you can find our fmuser office .
FMUSER Guangzhou office is in Tianhe District which is the center of the Canton . Very near to the Canton Fair , guangzhou railway station, xiaobei road and dashatou , only need 10 minutes if take TAXI . Welcome friends around the world to visit and negotiate .
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For Warranty .
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