One hertz is one cycle per second, meaning repeating cycle as an event. For example, hertz is applied physics measuring the number of times for a second wave (either acoustic or electromagnetic) is repeated or can be applied, among other uses, to ocean waves that reach the Beach vibrations per second or a solid. The quantity that measures the frequency hertz is called,in this regard, the inverse of the period. One hertz is an oscillation frequency of suffering a particle over a period of one second.

The global system for mobile communications (English Global System for Mobile communications, GSM, and originally from the French groupe spécial mobile) is a standard system, royalty-free, digital mobile phone. A GSM client can connect through your phone to your computer and send and receive emails, faxes, surf the Internet, access to the computer network security acompany (LAN/Intranet) and use other functions of digital data, including short message service (SMS) or text messages. What are the differences between GSM and UMTS? The GSM system operates by TDMA, ie, time is divided into slots and each user is assigned a slot, ie, a period for which data can be transmitted. Therefore each channel is shared by a ndetermined number of users. The system is a UMTS (WCDMA) code division multiple access broadband. In this system there are no time slots and GPRS. All users transmit simultaneously on the channel, but each user signals are encoded with a unique code so that even though we think that an "indecipherable signal" is formed by using the same frequencies simultaneously, It is not toyes, because the base station is capable of decoding and re perfectly separate each of the communications received from different users. This obviously implies a much higher channel utilization, to not share in time.

General Packet Radio Service (GPRS) or general packet radio service created in the 80s is an extension of the Global System for Mobile Communications (Global System for Mobile Communications or GSM) for the transmission of data by packet switching. A similar service for mobile phones, the IS-136 system. It allows transfer rates of 56-114 kbps. These Class A devicesThey can simultaneously use GPRS and GSM services. Only Class B may be connected to one of the two services at all times. While GSM service (voice or SMS) is used, the GPRS service, which automatically restarts when the GSM service ends is suspended. Most mobile phones are of this type. Class C are alternately connected to one or another service. Switching between GSM and GPRS shouldperformed manually.

Universal mobile telecommunications system (Universal Mobile Telecommunications System or UMTS) is one of the technologies used by mobile third-generation successor to GSM, because the GSM technology itself could not follow an evolutionary path to get to providing services considered third generation. Although initially is designed for use in mobile phones, the UMTS network is not LIMITADaa these devices and it can be used by others. What are the differences between GSM and UMTS? The GSM system operates by TDMA, ie, time is divided into slots and each user is assigned a slot, ie, a period for which data can be transmitted. Therefore each channel is shared by a number of users. The system is a UMTS (WCDMA) code division multiple access dand broadband. In this system there are no time slots and GPRS. All users transmit simultaneously on the channel, but each user signals are encoded with a unique code so that even though we think that an "indecipherable signal" is formed by using the same frequencies simultaneously, It is not, because the base station is capable of decoding and re perfectly separate each of the communicationsreceived from different users. This obviously implies a much higher channel utilization, to not share in time.

MiFi is a mobile router that acts as an access point to the Internet via 3G or later. You can connect to one or more devices at once by WiFi. It can be used with multiple WiFi devices such as desktops, laptops, tablets, smartphones, etc.

WAN, which is also known as wide area network is a network that consists of several private computers or organizations. Today with the speed that is in LANs is no longer necessary to use WAN

4G is the next generation of technology that the International Telecommunication Union has created for transferring data via the Internet. The speed is 100 MB/s downstream and 50 MB/s upstream, with a bandwidth of 20 MHz. The idea that used to wield the great value of 4G format that society is consuming more video and heavy images and this will make the mobile phone supports it. A continuación show you a small graphic comparison between 3G and 4G in the most common uses computer-related.

When we talk about RJ45 ("Registered Jack" 45) we refer to a telecommunications network interface for wired connection of voice and data equipment.

This connector has 8 pins or connections and may have a specific category depending on the data transfer speed and bandwidth (category 5e, 6, etc.)

The common application is their use in Ethernet network cables under TIA/EIA-568-B standard that defines the arrangement of pins (pinout), but can also be used for other applications.

- Direct pin diagram:

EIA-568A
Pin No.1: WHITE-GREEN
Pin No.2: GREEN
Pin No.3: WHITE-ORANGE
Pin No.4: BLUE
Pin No.5: WHITE-BLUE
Pin No.6: ORANGE
Pin No.7: WHITE-BROWN
Pin No.8: BROWN

EIA-568B
Pin No.1: WHITE-ORANGE
Pin No.2: ORANGE
Pin No.3: WHITE-GREEN
Pin No.4: BLUE
Pin No.5: WHITE-BLUE
Pin No.6: GREEN
Pin No.7: WHITE-BROWN
Pin No.8: BROWN

- Schematic of crossed pins:

The crossover cable has one end with EIA-568A scheme and the other one with EIA-568B.

Depending on the quality and type, network cables are classified into categories that help us know the characteristics of them.

The categories of network cables most commonly used are:

- Category 5
- Category 5e
- Category 6
- Category 6
- Category 7

As can be seen, category 5e (enhanced or improved) and category 6A (Augmented), are an improvement of categories 5and 6, respectively, which it has improved the top speed and bandwidth.

The higher the category, the higher the speed of maximum data, the maximum 100 meters distance as its standard.

You can see a table which shows the 5 categories, where V is the maximum velocity, D is the maximum and MHz frequency which can work away.