Question : what is DHCP? What is DNS? what is pop3? what is router? what is different between router and hub ? what is different between switch and router?     Answers: DHCP:Dynamic Host Configuration Protocol is... Read More

Question : 1.explain 7 osi layers briefly. 2.define router,gateways,brouter. 3.explain abt encryption & decryption.        Answers: 7 OSI LAYER IS A MODEL WHICH ARE DESCRIBE OPERATION HOW YOUR PACKET... Read More

Normally in IP address in fourth tab usually they will give the serial number of the using computer. in that case we can say how many computers are there. if not its impossiable to say. Read More

HUB When Ethernet was originally designed it used a single fat coax called a backbone. Individual hosts were physically connected to the backbone. This created a party line. Each host has to listen for the backbone to be idle before it started... Read More

PING stands Packet Internet Gopher. This is a utility for ensuring connectivity between computers . ICMP protocol works behind this utility. Under it , sending node sends packets to destination node and reply is received if there is proper... Read More

The address resolution protocol (ARP) is used to associate the 32 bit IP address with the 48 bit physical address, used by a host or a router to find the physical address of another host on its network by sending a ARP query packet that... Read More

An unspecified passive open has the server waiting for a connection request from a client. A fully specified passive open has the server waiting for a connection from a specific client. Read More

DHCP is only available on newer IOS-based switches. For example, Catalyst 3550 and 3750 offer DHCP. Let us take Cisco 2611 router running IOS12.2 To begin, connect the router's Ethernet port to a switch, and connect the switch to a... Read More

In a baseband transmission, the entire bandwidth of the cable is consumed by a single signal. In broadband transmission, signals are sent on multiple frequencies, allowing multiple signals to be sent simultaneously. Read More

It is a project started by IEEE to set standards that enable intercommunication between equipment from a variety of manufacturers. It is a way for specifying functions of the physical layer, the data link layer and to some extent the network layer to... Read More

Series of interface points that allow other computers to communicate with the other layers of network protocol stack. Read More

Bit rate is the number of bits transmitted during one second whereas baud rate refers to the number of signal units per second that are required to represent those bits. baud rate = bit rate / N where N is no-of-bits represented by each signal... Read More

HUb: limiteded port compare to switch.less speed compare to switch because more collision. Switch: To Avoid collision we use switch. In switch Each Port having own collision Domain. HUB:Hub is a layer-1 device,in this data transmission in... Read More

Server-based network. Peer-to-peer network. Peer-to-peer network, computers can act as both servers sharing resources and as clients using the resources. Server-based networks provide centralized control of network resources and rely on... Read More

The data unit in the LLC level is called the protocol data unit (PDU). The PDU contains of four fields a destination service access point (DSAP), a source service access point (SSAP), a control field and an information field. DSAP, SSAP are addresses... Read More

RAID stands for Redundant Array of Independent(or Inexpensive) Disk Drives that employ two or more drives in combination for fault tolerance and Performance. Read More

NETBIOS is a programming interface that allows I/O requests to be sent to and received from a remote computer and it hides the networking hardware from applications. NETBEUI is NetBIOS extended user interface. A transport protocol designed by... Read More

Transmission is a physical movement of information and concern issues like bit polarity, synchronisation, clock etc. Communication means the meaning full exchange of information between two communication media. Read More

A bridge is an layer 2 device - it works based on mac address. bridge is s/w based. It is usually used to bridge 2 networks (or even more in recent times) Bridge is configured by having the the mac address of the switches connected directly to... Read More

normally u can assigh one ip, if u ant to assign more than one ip , then u use diff LAN card(external lan card) Read More

An Directory is the database that holds information about component locations, users, groups, passwords, security, and other COM information. Some of this information is currently stored in the Registry, but will eventually (with Windows 2000) be... Read More

It is a set of rules defining a very simple virtual terminal interaction. The NVT is used in the start of a Telnet session. Read More

Hybrid devices that combine the features of both bridges and routers. Read More

 technology called VLAN (Virtual LAN broadcast domains logically segmented on an Ethernet switch) trunking that was once primarily the domain of network switches has now trickled down to the rest of the Data Center to address these issues. Now... Read More

Dial up connection requires a username/password & a modem to connect to internet.The maximum speed will be of 56kbps only. In this either the phone or the internet will work at a time. While in broadband connection (it need a modem & may... Read More

A network in which there are multiple network links between computers to provide multiple paths for data to travel. Read More

The address for a device as it is identified at the Media Access Control (MAC) layer in the network architecture. MAC address is usually stored in ROM on the network adapter card and is unique. Read More

Signals are usually transmitted over some transmission media that are broadly classified in to two categories:- Guided Media: These are those that provide a conduit from one device to another that include twisted-pair, coaxial cable and fiber... Read More

The degeneration of a signal over distance on a network cable is called attenuation. Read More

It is any routing protocol used within an autonomous system. Read More

A Hub is a Layer2 device. It is a Broadcast device which sends out the information to all the devices connected to it. It is a non-intelligent device which is used in smaller networks and increases the network traffic. A Hub is a multiport... Read More

POP3 is Email clients download your emails onto your computer. Using a specialized email program such as Outlook Express or Apple Mail has the advantage of giving you complete control over your email; every email you receive is placed on your... Read More

When hierarchical routing is used, the routers are divided into what we call regions, with each router knowing all the details about how to route packets to destinations within its own region, but knowing nothing about the internal structure of other... Read More

The three types of routing tables are fixed, dynamic, and fixed central. The fixed table must be manually modified every time there is a change. A dynamic table changes its information based on network traffic, reducing the amount of manual... Read More

Repeater: Also called a regenerator, it is an electronic device that operates only at physical layer. It receives the signal in the network before it becomes weak, regenerates the original bit pattern and puts the refreshed copy back in to the link.... Read More

Question : Why should we care about the OSI Reference Model ? What is the main purpose for creating this OSI model? Why it is a layered model? Answers: message's can transfer from one place to other .and the message not... Read More

When hierarchical routing is used, the routers are divided into what we call regions, with each router knowing all the details about how to route packets to destinations within its own region, but knowing nothing about the internal structure of... Read More

if there are more than one way for reaching a particular router from the same source router. 1.If TTL(time to live)field become zero. 2.Invalid destination. 3.if any fragment is lost. Read More

Advantages All the IP configuration information gets automatically configured for your client machine by the DHCP server. If you move your client machine to a different subnet, the client will send out its discover message at boot time and work... Read More

SIP is meant for Session Initiation Protocol. It works in application layer. It specially used for initiating, modifying and terminating a session. you can find all details in rfc3261. Read More

A Physical address is a 48-bit flat address burned into the ROM of the NIC card which is a Layer1 device of the OSI model. This iis divided into 24-bit vendor code and 24-bit serial address. This is unique for each system and cannot be changed. A... Read More

The Trivial File Transfer Protocol (TFTP) allows a local host to obtain files from a remote host but does not provide reliability or security. It uses the fundamental packet delivery services offered by UDP. The File Transfer Protocol (FTP)... Read More

10Base2?An Ethernet term meaning a maximum transfer rate of 10 Megabits per second that uses baseband signaling, with a contiguous cable segment length of 100 meters and a maximum of 2 segments. 10Base5?An Ethernet term meaning a maximum... Read More

To establish a connection, TCP uses a 3-way handshake. Before a client attempts to connect with a server, the server must first bind to a port to open it up for connections: this is called a passive open. Once the passive open is established then a... Read More

The function of PAD (Packet Assembler Disassembler) is described in a document known as X.3. The standard protocol has been defined between the terminal and the PAD, called X.28; another standard protocol exists between hte PAD and the network,... Read More

ICMP is Internet Control Message Protocol, a network layer protocol of the TCP/IP suite used by hosts and gateways to send notification of datagram problems back to the sender. It uses the echo test / reply to test whether a destination is... Read More

The data unit created at the application layer is called a message, at the transport layer the data unit created is called either a segment or an user datagram, at the network layer the data unit created is called the datagram, at the data link layer... Read More

A TCB is a complex data structure that contains a considerable amount of information about each connection. Read More

Every line has an upper limit and a lower limit on the frequency of signals it can carry. This limited range is called the bandwidth. Read More

When the computers on the network simply listen and receive the signal, they are referred to as passive because they don?t amplify the signal in any way. Example for passive topology - linear bus. Read More

The Mount protocol returns a file handle and the name of the file system in which a requested file resides. The message is sent to the client from the server after reception of a client's request. Read More

Frame relay is a packet switching technology. It will operate in the data link layer. Read More

It is using a router to answer ARP requests. This will be done when the originating host believes that a destination is local, when in fact is lies beyond router. Read More

It provides a framework for discussing network operations and design. Read More

Virtual channel is normally a connection from one source to one destination, although multicast connections are also permitted. The other name for virtual channel is virtual circuit. Read More

A layer of a glass surrounding the center fiber of glass inside a fiber-optic cable. Read More

DNS uses UDP for communication between servers. It is a better choice than TCP because of the improved speed a connectionless protocol offers. Of course, transmission reliability suffers with UDP. Read More

The HELLO protocol uses time instead of distance to determine optimal routing. It is an alternative to the Routing Information Protocol. Read More

The most common two letter combinations are called as digrams. e.g. th, in, er, re and an. The most common three letter combinations are called as trigrams. e.g. the, ing, and, and ion. Read More

A Management Information Base is part of every SNMP-managed device. Each SNMP agent has the MIB database that contains information about the device's status, its performance, connections, and configuration. The MIB is queried by SNMP. Read More

(i) Simplex (ii) Half-duplex (iii) Full-duplex. Read More

In a Ethernet network, between any two points on the network, there can be no more than five network segments or four repeaters, and of those five segments only three of segments can be populated. Read More

The basic difference is Forest is main domain who can control all tree on networks. Read More

The process that allows a network to self-repair networks problems. The stations on the network notify the other stations on the ring when they are not receiving the transmissions. Beaconing is used in Token ring and FDDI networks. Read More

Telnet is also called as terminal emulation. It belongs to application layer. Read More

i) Broadcast (ii) point-to-point. Read More

It is an Internet routing protocol that scales well, can route traffic along multiple paths, and uses knowledge of an Internet's topology to make accurate routing decisions. Read More

A pseudo tty or false terminal enables external machines to connect through Telnet or rlogin. Without a pseudo tty, no connection can take place. Read More

Vlan is virtual Lan... vlan have 2 main advantages: 1] it is used for security purpose, eg by making vlan u can diffenrentiate group. 2]u can increase collision domain, so collision is reduced Read More

It is a collection of routers under the control of a single administrative authority and that uses a common Interior Gateway Protocol. Read More

The header should have a minimum length of 20 bytes and can have a maximum length of 60 bytes. Read More

A generic term for section of a large networks usually separated by a bridge or router. Read More

One of the main causes of congestion is that traffic is often busy. If hosts could be made to transmit at a uniform rate, congestion would be less common. Another open loop method to help manage congestion is forcing the packet to be transmitted at a... Read More

Sending a message to a group is called multicasting, and its routing algorithm is called multicast routing. Read More

Routable protocols can work with a router and can be used to build large networks. Non-Routable protocols are designed to work on small, local networks and cannot be used with a router. Read More

DNS is called domain name server.it is used to resolved the ip address to domain name or vise versa. Read More

It is a sequence of IP addresses identifying the route a datagram must follow. A source route may optionally be included in an IP datagram header. Read More

One of two sublayers of the data link layer of OSI reference model, as defined by the IEEE 802 standard. This sublayer is responsible for maintaining the link between computers when they are sending data across the physical network connection. Read More

It is a simple protocol used to exchange information between the routers. Read More

It is an authentication service developed at the Massachusetts Institute of Technology. Kerberos uses encryption to prevent intruders from discovering passwords and gaining unauthorized access to files. Read More

BUS topology: In this each computer is directly connected to primary network cable in a single line. Advantages: Inexpensive, easy to install, simple to understand, easy to extend. STAR topology: In this all computers are connected using a... Read More

Packet filter is a standard router equipped with some extra functionality. The extra functionality allows every incoming or outgoing packet to be inspected. Packets meeting some criterion are forwarded normally. Those that fail the test are dropped. ... Read More

Class A 0.0.0.0 - 127.255.255.255 Class B 128.0.0.0 - 191.255.255.255 Class C 192.0.0.0 - 223.255.255.255 Class D 224.0.0.0 - 239.255.255.255 Class E 240.0.0.0 - 247.255.255.255 Read More

Hub: A passive device, Can't support full duplex, can't support 100 Mbps Mode, Can't store port wise MAC Addresses. Switch: A Active devise, it can support 10 base_T full/half and also 100 base_T full/half, and in higher end it... Read More

Anonymous FTP enables users to connect to a host without using a valid login and password. Usually, anonymous FTP uses a login called anonymous or guest, with the password usually requesting the user's ID for tracking purposes only. Anonymous... Read More

Request to Exit (REX) - A signal that informs the controller that someone has requested to exit from a secure area. Read More

A protocol that assures accurate local timekeeping with reference to radio and atomic clocks located on the Internet. This protocol is capable of synchronising distributed clocks within milliseconds over long time periods. It is defined in STD 12, ... Read More

POP3 and IMAP4 are used to retrieve mails. IMAP4 stores a copy of message on the server whereas POP3 does not. Read More

Piggybacking is gaining access to restricted communication channel by using session that another user has already established. Piggybacking can be defeated by logging off before leaving a workstation or terminal or by initiating a protected mode,... Read More

255.255.255.255.255.0 Read More

we can use static and Dynamic Routing in one network. However Dyanmic Routing is used to have the best path no matter what the status of the physical links.All routing protocols have some sort of shortest-path or lowest-cost or best-choice algorithm... Read More

A portion of a network that shares a common address component. On TCP/IP networks, subnets are defined as all devices whose IP Address have the same prefix. For example, all devices with IP addresses that start with 100.100.100. would be part of... Read More

The Network Time Protocol (NTP) is a protocol for synchronising the clocks of computer systems over packet-switched, variable-latency data networks. NTP uses UDP as its transport layer. It is designed particularly to resist the effects of... Read More

1 synchronous txn 2 asynchronous txn Read More

It is a protocol used to advertise the set of networks that can be reached with in an autonomous system. BGP enables this information to be shared with the autonomous system. This is newer than EGP (Exterior Gateway Protocol). Read More

It is a problem that can ruin TCP performance. This problem occurs when data are passed to the sending TCP entity in large blocks, but an interactive application on the receiving side reads 1 byte at a time. Read More

A communications protocol used to connect computers to remote networking services including Internet service providers. Read More

These are all different things in networking. Hub:Where we connect all the the links for a networking connection. Node:It can be identified as a one connection. Host:is nothing than if you are going to send a request to the server the questioned... Read More

In Microsoft Office Outlook 2003, a new offline folder file format is introduced that offers greater storage capacity for items and folders and supports multilingual Unicode data. An offline file folder is used to keep a local copy of your Exchange... Read More

Broadcast Domain: A set of all devices that recieve broadcast frames originating from any device within the set. Broadcast domains are typically bounded by routers (or, in a switched network, by VLANs) because routers do not forward broadcast frames.... Read More

It is the protocol the routers in neighboring autonomous systems use to identify the set of networks that can be reached within or via each autonomous system. Read More

Along any transmission path from a given source to a given destination, a group of virtual circuits can be grouped together into what is called path. Read More

In token Ring , hub is called Multistation Access Unit(MAU). Mau is connect two or more pc together in network. Read More

If u want to access ur corporate network from ur public network(internet) u have to use VPN. It carries the data in a secured mode in public network. For this u need to install VPN software n u need some authentication for that from u r company.... Read More

Maximum Transmission Unit is the largest physical packet size, measured in bytes, that a network can transmit. Any messages larger than the MTU are divided into smaller packets before being sent. Every network has a different MTU, which is set by... Read More

CIDR (Classless Inter-Domain Routing) is a way to allocate and specify the Internet addresses used in inter-domain routing Read More

It is a system that performs a protocol translation between different electronic mail delivery protocols. Read More

routing depends on ip address : layer 3 s/w routing depends on mac- address : layer 2 s/w Read More

It is a protocol formerly used to exchange routing information between Internet core routers. Read More

DNS- Domain Name Server or Services. WINS- Windows Internet Name Service. DNS is resolve the web site name to IP address or you can say. In WINS used a file name those is LMhost, this file in the System32, and when we put the websit name and its... Read More

External Data Representation is a method of encoding data within an RPC message, used to ensure that the data is not system-dependent. Read More

Frames Packet data unit(PDU)is called ---------------- segment at transport layer packet at a network layer frame at data link and bit/bytes at physical layer Read More

It is a very simple protocol used for transmission of IP datagrams across a serial line. Read More

Redirector is software that intercepts file or prints I/O requests and translates them into network requests. This comes under presentation layer. Read More

A gateway operates at the upper levels of the OSI model and translates information between two completely different network architectures or data formats. Gateway provide the bestpath to the system to reach the server in the same network ... Read More

Recovery Console:That helps you restore your operating system when you cannot start your system. Read More

Emergency Repair Disk, an ERD is a diskette that creates backups of important system files and settings and is used to help troubleshootand fix issues for Microsoft WINNT and WIN 2000. The ERD is used in conjunction with the Windows repair option... Read More

First of all what is VPN." VPN " stand for Virtual Private Network .Next how it works and where it is used . VPN works when the IP Conficts and IP is conflict because we dont use the PUBLIC IP means the IP we use is may be used by onther Company or... Read More

Question : Why should we care about the OSI Reference Model ? What is the main purpose for creating this osi model? why it is a layered model? Answers: It is very important model for networking: The main aim to design the OSI model is... Read More

Email Client Email clients download your emails onto your computer. Using a specialized email program such as Outlook Express or Apple Mail has the advantage of giving you complete control over your email; every email you receive is placed on your... Read More

Interior gateways connect LANs of one organization, whereas exterior gateways connect the organization to the outside world. Read More

PING TRACEROUTE PATHPING Read More

obviously it s time to live(TTL) it fixes up a time to reach,if it s not reached within that stipulated time,it is being killed by the auto timer... Read More

A resource record is an entry in a name server's database. There are several types of resource records used, including name-to-address resolution information. Resource records are maintained as ASCII files. Read More

Supernetting refers to increase host and reduce the subnet's. It mean reduce the network bits and increase the host bits. We do use supernetting because when the PCs in the network increase where we need the more valid IP's in the same... Read More

Question : Difference between the communication and transmission. Transmission is a physical movement of information and concern issues like bit polarity, synchronisation, clock etc. Communication means the meaning full exchange of... Read More

RAID - Redundant Array of Independent / Inexpensive Disks. RAID has many different levels such as 0 1 2 3 4 5 10 01 etc. Read More

No answer available currently. Be the first one to reply to this question by submitting your answer from the form below.   Read More

It is a host that has a multiple network interfaces and that requires multiple IP addresses is called as a Multi-homed Host. Read More