VSAT represents a Very Small Aperture Terminal. It is a two-way satellite ground terminal with a dish wire that is lower than 3 meters. It is generally used to transmit narrowband data (point of sale transactions such as credit card, polling) or broadband information (for the provision of satellite internet access to remote areas, VOIP or video). It is also used for mobile communications.Features of VSATBand L has a Bandwidth of 15 MHz where Downlink frequency is 1.5 GHz, and Uplink frequency is 1.6 GHz. For Band S, Bandwidth is 70 MHz where Downlink is 1.9 GHz, and Uplink is ... Read More

There are various types of ETHERNET Cables which are as follows −10Base 5The first standard defined in IEEE 802.3 is 10 Base 5. It is a Thick Ethernet or Thicknet. It is a bus topology LAN with baseband signaling. The data speed is 10 Mbps, and the maximum allowed segment length is 500 meters. The bus's total length should not exceed 2500 meters, i.e., with a segment of 500 meters, each resulting in only five segments to be used. Each station should be separated from its neighbours by 2.5 meters, i.e., only 200 stations are permitted in maximum in each ... Read More

Ethernet is a LAN architecture developed by XEROX and extended by DEC, IC and Xerox. It is specified by IEEE 802.3, and it defines two categories.These categories are as follows−BasebandBroadbandBaseband uses digital signals, while broadband uses analog signals. Baseband is further divided into five standard names as follows −10 Base 510 Base 210 Base T1 Base 5100 Base TThe first numbers used in all standards, i.e., 10, 1, 100, indicate the data rate in Mbps, while the last numbers 2, 5, and letter T indicate the maximum cable length or type of cable. Only one specification is defined for broadband, ... Read More

There are various network security threats and attacks which are explained below−Natural DisastersEarthquakes, floods, lightning, and fire can cause several damages to computer systems. It could include other threats such as riots, wars, and terrorist attacks could be included here. Although they are human-caused threats, they are classified as disastrous.Deleting and altering dataMalicious attackers who delete or alter data usually do this to prove a point or take revenge for something that has occurred to them. Inside attackers frequently do this to spite the organisation because they are disgruntled about something. Outside attackers might need to prove that they can ... Read More

The objective of the network is to send data among its users located locally or remotely. Hence, it is possible that undesired users can hack the web and prove harmful to the network or the user's health.The network administrator should follow a few essential points to provide the network with adequate security other than network-specific security, such as e-commerce. These are given below:Networks are designed to share data. Therefore, it should configure the network to identify shareable data and non-shareable data.The network must also clear with whom can share the shareable data.With the increase of network security, the cost for ... Read More

SMTP represents Simple Mail Transfer Protocol. SMTP is a set of interaction guidelines that allow the software to transmit electronic mail over the internet, referred to as Simple Mail Transfer Protocol.The main objective of SMTP is used to set up communication rules between servers. The servers have a way of recognizing themselves and announcing what kind of communication they are trying to perform. They also have a way of handling errors such as incorrect email address. For example, if the recipient address is wrong, then receiving a server reply with an error message of some kind.Working of SMTPSMTP is an ... Read More

TFTP operation is very simple. The client sends a read or write request at the server's UDP port 69. The server accepts the request by sharing data messages in case of the read request and sending acknowledgement in the write request. In either case, the server chooses a UDP port for further dialogue and sends its first response to the client through the selected UDP port.Each data message has a fixed size of the data block (512 octets) and is individually acknowledged. The last data block containing EOF (End of File) or a data block containing less than 512 octets ... Read More

TFTP represents the Trivial File Transfer Protocol. Some applications do not need the full functionality of TCP, nor can they afford the complexity. TFTP supports an inexpensive structure that does not require complex interactions between the client and the server. TFTP confine operations to simple File Transfer and does not support authentications.The benefit of using TFTP is that it enables bootstrapping code to use the similar underlying TCP/IP protocols that the operating framework uses once it starts execution. Thus it is the possibility for a device to bootstrap from a server on another physical network.TFTP does not have a dependable ... Read More

When using File Transfer Protocol (FTP), the user implements some or all of the following operations −Connecting to a remote hostTo implement a file transfer, the user begins by logging into the remote host. Four commands are used.Open selects the remote host and sets up the login session.User recognizes the remote user ID.Pass authenticates the client.Site sends data to the foreign host that is used to provide services specific to that host.Navigating the directory structureAfter a client has been authenticated and logged on to the server, that client can navigate through the remote host's directory structure to locate the file ... Read More

The two types of Connections in FTP are as follows −Control ConnectionThere are two steps −The server issues a positive open on the well-known port 21 and waits for a client.The client uses an ephemeral port and issues an active open.The connection remains open during the whole process.Data ConnectionThe data connection facilitates the well-known port 20 at the server site. The following steps display how FTP creates a data connection.The user, not the server, issues a passive open using an ephemeral port.The client assigns this port number to the server using the PORT command.The server receives the port number and ... Read More