Computer networks two marks questions and answers pdf

The server has two components: GE Computer Programming 4. The UA prepares the message, creates the envelope, and puts the message in the envelope. Write the keys for understanding the link state routing. A router gets its coomputer about its neighbors by periodically sending them a short greeting packets. In longitudinal redundancy check LRCa block of bits is divided into rows and a redundant row of bits is added to the whole block.

These bitts are called framing bits. Thus flow control is an end to an end issue, while congestion control is concerned with how hosts and networks interact. CS — Computer Networks Page 12 of 24 6. Why Ethernet is said to be a I -persistent protocol? If a frame is corrupted comuter transit, a NAK ansewrs returned and the frame is resent out of sequence.

Security issues include protecting data from unauthorized access and viruses. What is the function of FECN? Here each entity can create a pair of keys, keep the private one, and publicly distribute the other one. In the NRZ-L sequence, positive and negative voltages have specific meanings: The quality of service defines a set of attributes related to the performance of the connection. Pretty Good Privacy is used to provide security for electronic mail.

Calculating the cipher text using the long keys takes a lot of time. A Character level encryption in which the characters retain their plaintext but the position of the character changes. Means that 2 or more bits in the data unit have changed from 1 to 0 from 0 to 1.

A protocol is a set of rules that govern data communication. What are the four aspects related to the reliable delivery of netwoks Using Qestions, encode the bit stream What are the three pieces of information in the configuration messages?

In network transactions, you can create an equivalent of an electronic or digital signature by the way you send data. Anna University — B. The quality of service defines a set of attributes related to the performance of the connection. Where is the Menu?

A simple example of modulation is to vary the power amplitude of a single wavelength. Mobility and hosts:Hosts may move between networks without reconfiguring. Mobility of network:Possible for internet service providers to reconfigure customers address transparently. Save address space if individual clients are not always active.

What are the services offered by network layer? Packets in the IP layer are called datagrams. An IP address is a numerical label assigned to each divide in a computer network that uses internet protocol for communication.

Two important functions at IP address 1. Host identification 2. Location addressing How can the routing be classified? The routing can be classified as, Get Unique study materials from www. Salient features are : 1. Efficient and hierarchical addressing and routing infrastructures. IPv6 networks provide auto configuration capabilities. Better support for QOS. Large Address space. UNIT 4 1. Does not include the overhead needed to detect and maintain connection oriented semantics.

TCP provides a connection oriented,reliable byte stream service. The connection oriented means the two applications using TCP must establish a TCP connection with each other before they can exchange data. Define congestion When too many packets rushing to a node or a part of network, the network performance degrades so this situation is called as congestion. TCP header contains six flags. Give the approaches to improve the QOS.. Fine grained approaches , which provide QOS to individual applications or flows.

Quality of Service is used in some organizations to help provide an optimal end user experience for audio and video communications. Qos is most commonly used on networks where bandwidth is limited:with a large number of network packets competing for a relatively small amount of available bandwidth. The job of gathering data chunks at the sourcs host from different sockets, encapsulating each data chunks with header information to create segments, and passing the segments bto the network layer is called multiplexing.

RTT is an acronym for Round Trip Time: it is a measure of the time it takes for a packet to travel from a computer , across a network to another computer, and back.

Transport layer protocols send data as a sequence of packets. Applications running on different hosts communicate with TCP with the help of a concept called as ports. A port is a 16 bit unique number allocated to a particular application. Guarantee message delivery. Delivery messages in the same order they are sent. Deliver at most one copy of each message. Support arbitrarily large message. Support synchronization. When load on network is greater than its capacity, there is congestion of data packets.

Congestion occurs because routers and switches have queues or buffers. What are the functions of transport layer? Breaks messages into packets. Provide reliability List some ways to deal with congestion 1. Flow control 3. Buffer allocation 4. Choke packets Define a network congestion? What are the flow characteristics related to QOS? What are the techniques to improve QOS? What are the two types of protocols used in Transport layer? Define Throughput. It is defines as a number of packets passing through the network in a unit of time What is the need of port numbers?

Port numbers are used as a addressing mechanism in transport layer What are the types of port numbers used in transport layer? Why TCP services are called Stream delivery services?

TCP allows the sending process to deliver data as a stream of bytes and the receiving process to deliver data as a stream of bytes. Define jitter Get Unique study materials from www.

Unicast communication is one source sending a packet to one destination. Multicast communication is one source sending a packet to multiple destinations. UNIT 5 1. GUI based:They contain GUI components that allow the user to interact with the software by using both the keyword and mouse. What is DNS? The inverse domain is used to map an address to a name. Simple Mail Tranfer Protocol is a standard and reliable host to host mail transport protocol that operates over the TCP port These configuration and monitoring capabilities are collectively referred to as management.

What is the Domain name system responsible for? The Domain name system converts domain names of the form www. Global Uniform Resource Identifier 2. Request response exchange. Resource metadata 8. What is SMTP used for? What is virtual terminal? A virtual terminal is a data structure maintained by either the application software or a local terminal.

Define www? It is an internet application that allows users to wiew web pages and move from one web page to another. Web browser is a software program that interprets and displays the contents of HTML web pages. What is URL?