MCSE

Adding 1’s as a bit means increasing the subnets and decreasing the hosts. Removing or decreasing 1’s means decreasing subnets and increasing hosts. Hence by increasing or decreasing the subnet architecture can be decided as per needs.

A subnet mask allows identification of host part and network part of an IP address. Subnet mask can be used to find if an IP address is present on a subnet or not.

Real-Time Transfer Protocol lays a standard or a way to transfer or manage real time data over a network. It does not guarantee the delivery of data or provide any quality of service. However it helps to manage the data. Which means that RTP can be used deliver the necessary data to the application to make sure it can put the received packets in the correct order Real time data examples could be audio and video

RTP multiplexing allows multiple media flows within a single RTP data payload between two points. This means that it can be used to carry multiple streams of data in one RTP packet. RTP multiplexing will reduce the bandwidth used. RTP multiplexing will also increase scalability.

Use of RTP and RTCP:-

1. RTP can be used to transfer Real time data like voice packets.

2. RTP can be used with RTCP which makes it possible to monitor data.

3. Packet loss can be detected by RTP using Sequence number

RTCP provides Qos feedback :- Packets lost, round trip time

Multicasting allows a single message to be sent to a group of recipients. Emailing, teleconferencing, are examples of multicasting. It uses the network infrastructure and standards to send messages.

IP multicast technology reduces traffic by sending stream of information to many recipients at one go. Video conferencing, stock quotas are the examples based on IP multicast.

Multicast protocol or Internet protocol delivers a singles message to multiple machines. One packet from the source is replicated and sent to the destination. Every multicast message requires a multi case group. The group defines the addresses which will receive the message. The group is defined by the class D address. Different routing protocols are used to find the multicast groups and build routes for them. Distance Vector Multicast protocol is one of them. The receiver, to whom the multicast packet is sent to, needs to ‘join’ the group. Joining the group is enabled and managed by IGMP. Multicast routers are used to transmit the messages from one network to another.

Controlling the scope of multicast transmission restricts the range of group members. TTL (Time To Live) is one of the mechanisms to limit the scope. If the TTL value is small, packets would only be multicast to smaller distance destinations. More the value of TTL, more would be the scope of transmission to a larger number of machines. Administrative scoping is another mechanism. In this, transmission is restricted to a specific address space of an organization or a site.

* a. When the same message or packet needs to be sent to multiple destinations, multicasting is used.

* b. Within campus and offices, using multicasting file distribution can be done.

* c. System messages, news and videos can be sent at the same time.

* d. More commonly used for audio and video streaming.

A socket is used to connect an application to a network protocol. A socket enables communication between a client and a server. The communication is started when the client is assigned a local port number, and binds a socket to it. The client writes on the socket and gets information from server by reading it.

Stream can be considered as a pipe that allows full duplex connection. A datagram or a packet on the other hand, has a source and a destination. There is no connection. Stream is like a communication channel while datagram is completely self contained. Streams provide a reliable and sequenced communication. Datagram’s on the other hand are unreliable and no sequence maintained.

A stream socket provides two way communications between a client and server. This communication is reliable and sequenced. Stream sockets are above TCP to run across any networks. They provide unduplicated flow of data and have well established mechanism for creating and destroying connections and for detecting errors.

IP address or Internet Protocol address is the address of a device attached to an IP network (TCP/IP network). It is a must for every client, server and network device to have a unique IP address for each network connection (network interface). Every IP packet contains a source IP address and a destination IP address. As a device moves from one network to another, its IP address changes.

Static IP is also called as permanent address assigned to each device in a network, whereas Dynamic IP, a temporary address assigned to the device via DHCP software. IP address assigned to your service by your cable or DSL Internet provider is typically dynamic IP. In routers and operating systems, the default configuration for clients is dynamic IP

A public IP address allows equipment accessible to everyone on the internet. A private IP address is for private use within the network and allows many more PCs to be connected. If you are using a private IP and wants VOIP, you need to change to a public IP address.

Network Address Translation acts as an agent between the Internet and a local network. It is a dynamic method which is used to minimize Internet connectivity needs. Network address translation describes the rewriting of the Internet Protocol (IP) addresses of data packets so that multiple transmissions require only one IP address.

IP multicast technology reduces traffic by sending stream of information to many recipients at one go. Video conferencing, stock quotas are the examples based on IP multicast.

Subnet adds one level to the way IP address is represented. It logically organizes the network. For instance, it can logically group computers belongs to the finance department.