Warning over satellite security bugs..

Satellite systems used on aircraft, ships and by the military contain bugs that could hackers take control of the a security researcher has warned.....

The worst bugs could let attackers overcharges satellite antenna to damage the equipment or harm operators and other could be used to betray the exact location of military forces in crisis zones the researcher said. IoActive which found the bugs said  it was working with manufactures to harden devices against attack.

TYPES OF NETWORKING DEVICES

1) NIC- NIC stand for network interface card. It is indeed a circuit board or a card that is installed in a computer so that it can be connected to a network. The network interface card provides the computer with a dedicated, full-time connection to a network. Personal computer and workstations on a local area network(LAN) typically contain a network interface card specifically designed for the LAN transmission technology.

2) REPEATER- Repeater is a network device, which used to regenerate or replicate a signal. It removes the unwanted noice in an incoming signal. Unlike an analog signal, the original signal, even if weak or distorted, can be clearly perceived and restored. With analog transmission signal are re-strengthened with amplifiers which unfortunately also amplify noise as well as information.

3) HUB- Basically a hub is a common connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contain multiple ports. When a packet arrives at one port it is copied to the other ports so that all segments of the LAN can see all packets.

4) BRIDGE- Bridge devices inspect incoming network traffic and determine whether to forward or discard it according to its intended destination. An Ethernet bridge for example, inspects each incoming Ethernet frame-including the source and destination MAC addresses, and sometimes the frame size in making individual forwarding decisions.

5) SWITCH- Switch is a very common types of networking device that channels coming data from any of multiple input ports to the specific output port that will take the data toward, its intended destination in a telecommunications network. In the traditional circuit-switched telephone network one or more switch are used to set up a dedicated communication through temporary connection or circuit for data exchange between two or more network devices. On an Ethernet LAN the switch determines from the physical devices like MAC address in each incoming message frame which output port to forward it to and cut of. In an internet a switch determines from the IP address in each packet, and the output port of switch is connected to the next part of the intended destination.

6) GATEWAY- A gateway is a network node which connects two network in different protocols. Gateway can take a several forms including routers or computers and can perform a variety of tasks.

7) ROUTER- Router is one of the most used networking devices used to sharing internet connection between two devices. The operating of router is complicate as it can be both software and hardware and operate at layer 3 of OSI model.

8) MODEM- MODEM stands for modulator-demodulator. A modem is a device or program that enables a computer to transmit data over. Computer information is stored digitally whereas information transmitted over telephone lines is transmitted in the form of analog waves. A modem converts between these two forms analog to digital and vice versa.

OSI MODEL LAYERS |

                                                            OSI MODEL

• PHYSICAL LAYER :- This layer is primary layer of the osi model and consists of connection  devices such as Ethernet cable, Token ring, Hubs, Repeaters and electrical specification for data connection. 

• DATA LINK LAYER :- Data link layer encodes and decodes data packet into bits and using its transmission protocol it handles the errors in the physical layer. this is work on Switch.  MAC address, NIC, Bridge, Framing, Encapsulation, or Error detection.

• NETWORK LAYER :- The Network layer adds the concepts of routing above the Data link layer. Tagging IP Address, Choose best path, Routing. Most used protocol in this layer is internet protocol(IP), Internet packet exchange(IPx), ARP, RARP etc.

• TRANSPORT LAYER :- In the fourth layer variable length data sequence has to be transferred from source to destination host through one or more network. This transport layer delivers data across network connection. The supported prrotocols at this layer are TCP(Transmission control protocol) UDP(User datagram protocol) and SPX(Sequential packet exchange).

• SESSION LAYER  :- Create and manage the session via port number is know as session layer.  Synchronization, Dialog, Control, Reconnection.

• PRESENTATION LAYER :- The presentation layer is the simplest in function of any piece of the OSI model. It handles syntax processing of message data such as format conversions and encryption/decryption needed to support the application layer above it. File Formats are Mp4, AVI, MKV, PNG, JPG etc.

• APPLICATION LAYER :- This is last layer of OSI model and this layer represents the data that is understood by the end user. The application layer supplies network services to end user application. Protocols are FTP, HTTP, HTTPS, TELNET, DNS, SMTP, POP  etc..