NAME OF THE EXPERIMENT: Broadcast Tree. AIM: Implement broadcast tree for a given subnet of hosts HARDWARE REQUIREMENTS: Intel-based Desktop PC :- RAM of 512 MB SOFTWARE REQUIREMENTS:   Turbo C / Borland C. THEORY:   This technique is widely used because it is simple and easy to understand. The idea of this algorithm is to build a graph of the subnet with each node of the graph representing a router and each arc of the graph representing a communication line. To choose a route between a given pair of routers the algorithm just finds the broadcast between them on the graph. ALGORITHM/FLOWCHART: step 1: declare variable as int p,q,u,v,n; step 2: Initialize min=99,mincost=0; step 3: declare variable as int t[50][2],i,j; step 4: declare variable as int parent[50],edge[50][50]; step 5: Begin step 6: write "Enter the number of nodes" step 7: read "n" step 8: Initialize i=0 step 9:  repeat step(10-12) until i<n step10: inc

    Address Mapping:  Ø The  delivery of a packet to a host or router requires two levels of addressing: Logical and physical. Ø    We need to map logical address to its corresponding physical address and vice versa. Ø    This can be done by  Static mapping and Dynamic mapping. Ø    Static mapping  involves in the  creation of a table that associates a logical address with a physical address.  This address mapping table is  stored in each device  on the network. Ø    Static mapping has some limitations because physical addresses may change in the following ways: ·       A machine could  change its Network Interface Card (NIC)  , which results in a new MAC address. ·        In some Local Area Networks(LAN), such as  Local Talk, the MAC address changes every time the computer is turned on. ·        A  mobile device can move from one physical network to another, which results in a change in its MAC address. Ø    To implement these changes, a static mapping table mu

Session Layer: Ø   Session layer in OSI reference model is responsible for establishing, maintaining and terminating the sessions . Ø    Session Layer   is also called as Layer 5 of OSI layer. Ø   It deals with sessions or interactions between the applications(Live example of Phone call) Ø   Session ID is used to identify a session or interaction. Ø   Ex: RPC,SQL,NFS Specific Responsibilities of Session Layer in Computer Network: Ø   Dialog control: The session layer allows two systems to enter into a dialog . It allows the communication between two processes to take place in either half-duplex (one way at a time) or full-duplex (two ways at a time) mode. Ø   Synchronization: The session layer allows a process to add checkpoints, or synchronization points , to a stream of data. For example, if a system is sending a file of 2000 pages, it is advisable to insert checkpoints after every 100 pages to ensure that each 100-page unit is received and acknowledge

Domain Name System (or Service or Server): Ø   When DNS was not into existence, one had to download a Host file containing host names and their corresponding IP address. Ø   But with increase in number of hosts of internet, the size of host file also increased. Ø   This resulted in increased traffic on downloading this file . To solve this problem the DNS system was introduced. Ø   It is an  internet  service that translates  domain names  into IP addresses. Ø   Because domain names are alphabetic, they're easier to remember . Ø   The Internet however, is really based on  IP addresses . Ø   Every time you use a domain name, therefore, a DNS service must translate the name into the corresponding IP address. Ø   For example, the domain name  www.example.com  might translate to  198.105.232.4 . Ø   It uses a hierarchical naming scheme and distributed database of IP addresses and associated names. Ø   If one DNS server doesn't know how to translate a par

Domain Name System Architecture: Ø   The Domain name system comprises of Domain Names, Domain Name Space, Name Server that have been described below: a)     Domain Names:   Ø   Domain Name is a symbolic string associated with an IP address . Ø   Each node in the tree has a domain name. Ø   A full domain name is a sequence of labels separated by dots (.). Ø   The domain names are always read from the node up to the root . Ø   The last label is the label of the root (null) . This means that a full domain name always ends in a null label , which means the last character is a dot because the null string is nothing .   Fully Qualified Domain Name Ø   If a label is terminated by a null string [null means nothing, the label ends with a dot (.) ] , it is called a fully qualified domain name .(FQDN). Ø   An FQDN is a domain name that contains the full name of a host. Ø   It contains all labels, from the most specific to the most general, that uniquely