Instructions . Mention Your Name, Id and section Number clearly For safe assignm
ID: 3698827 • Letter: I
Question
Instructions . Mention Your Name, Id and section Number clearly For safe assignments if any students copy from 80 to 90 percent then 10% mark will be deducted. If any students copy from 90 to 100 percent then 20% marks will be deducted . . Any late assignment will not be accepted Submit soft copy through corresponding links . Cheating is prohibited( zero marks) Course message submission is not accepted Late penalty of a student who submitted her assignment after due date is 10% deducted from the marks for first day and 20% for second day and so on Assignment-IL Question (3 Marks) Briefly discuss the role of following devices in the context of networking. [ 2 Marks] 1.1 Modem 1.2 Switch 1.3 Repeater 1.4 Gateway 2. If we can extend the LAN then why we need a WAN? [1 Mark >>View/CompleteExplanation / Answer
1.1)Answer:
Modem:
A modem is a network device that both modulates and demodulates analog carrier signals (called sine waves) for encoding and decoding digital information for processing. Modems accomplish both of these tasks simultaneously and, for this reason, the term modem is a combination of "modulate" and "demodulate."
Computer information is storeddigitally, whereas information transmitted over telephone lines is transmitted in the form of analog waves. A modem convertsbetween these two forms.
The most common use for modems is for both sending and receiving of the digital information between personal computers. This information used to be transmitted over telephone lines using V.92, the last dial-up standard, to an analog modem that would convert the signal back to a digital format for a computer to read.
Now, access to the Internet more commonly takes place using high-speed broadband modems.
1.2)Answer:
Switch:
A switch, in the context of networking is a high-speed device that receives incoming data packets and redirects them to their destination on a local area network (LAN). A LAN switch operates at the data link layer (Layer 2) or the network layer of the OSI Model and, as such it can support all types of packet protocols.
Essentially, switches are the traffic cops of a simple local area network
A switch in an Ethernet-based LAN reads incoming TCP/IP data packets/frames containing destination information as they pass into one or more input ports. The destination information in the packets is used to determine which output ports will be used to send the data on to its intended destination.
Switches are similar to hubs, only smarter. A hub simply connects all the nodes on the network -- communication is essentially in a haphazard manner with any device trying to communicate at any time, resulting in many collisions. A switch, on the other hand, creates an electronic tunnel between source and destination ports for a split second that no other traffic can enter. This results in communication without collisions.
Switches are similar to routers as well, but a router has the additional ability to forward packets between different networks, whereas a switch is limited to node-to-node communication on the same network.
1.3)Answer:
Repeater:
A repeater is a network device that retransmits a received signal with more power and to an extended geographical or topological network boundary than what would be capable with the original signal.
A repeater is implemented in computer networks to expand the coverage area of the network, repropagate a weak or broken signal and or service remote nodes. Repeaters amplify the received/input signal to a higher frequency domain so that it is reusable, scalable and available.
Repeaters were introduced in wired data communication networks due to the limitation of a signal in propagating over a longer distance and now are a common installation in wireless networks for expanding cell size.
Repeaters are also known as signal boosters.
1.4)Answer:
Gateway:
A gateway is a data communication device that provides a remote network with connectivity to a host network.
A gateway device provides communication to a remote network or an autonomous system that is out of bounds for the host network nodes. Gateways serve as the entry and exit point of a network; all data routed inward or outward must first pass through and communicate with the gateway in order to use routing paths. Generally, a router is configured to work as a gateway device in computer networks.
2)Answer:
A bridge LAN is not considered a wide area technology because bandwidth limitations prevent a bridge LAN from serving arbitrarily many computers at arbitrarily many sites. Performance issue, an in LAN shared medium is used and only two computers are communicate at one time and where as in WAN more than two computers can communicate at one time. Scalability is another issue; a WAN must be able to grow as needed to connect many sites spread across large geographic distance, with many computers at each site. Scalability is very expensive in the extended LAN