Routers : What Are Routers?

“Networks are all around us. They are in our walls, in the air. At schools, hotels, hospitals, even coffee shops. Always there, always on…This power exists today. In our routers. In our switches... . (Cisco, n.d.)

3: Network Layer: The use of network layer is switching and routing technologies. It demonstrates logical path and virtual circuits for transferring data from one node to

D. Routers are Layer 2 devices, so they can connect to LANs but not WANs.

gateway. When the data packets reach their destination, they fit back together to for the

Bridge is a simple device that aids in interconnecting similar LAN's between local area networks that use identical protocols for the physical and data link layers in accordance with the IEEE 802.3 standards. As the devices connected to the bridge use the same protocols, the amount of processing required is minimal. Nowadays, routers are used more commonly to interconnect LAN’s as bridges are Layer 2 devices and pose almost no security while the router is a Layer 3 device and offers better Data Security.

A Router is a Layer 3 or Network layer device that connects a network to another network. It connects networks with the same protocol such as RIP (Routing Information Protocol) and IP (Internet Protocol).

1. For what purpose is a transceiver used? A transceiver can be used for converting one type of Ethernet connector to another or by converting one type of I/O port to an Ethernet port. 2. This lab connects routers directly to each other via serial cables. Is this a typical configuration? No, By default, Cisco routers are DTE (Data Terminal Equipment)/ DCE (Data Circuit-Terminating Equipment) If not, to what equipment does the DCE end of the serial cable usually connect? If Router A is connected to the DTE end of the cable, Router B must be connected to the DCE end 3. What does a rollover (console) cable look like? Rollover cable is often used to connect a computer terminal to a

| Given a network topology of two or more routers and an IPv4 addressing scheme, implement static routing and confirm layer 3 connectivity.

In this example, we have three routers A, B and C. C’s E0 is directly connected to 192.168.3.0. And C’s routing table is (192.168.3.0; 0; E0) which shows that 192.168.3.0 is 0 hop away. RIP (Routing Information Protocol), running on C, tells B that 192.168.3.0 is reachable through C with a distance of 0. B adds 1 hop to the distance and enters the route to 192.168.3.0 into its own routing table which becomes (192.168.3.0; 1; S1). Now RIP is running on B and tells C that 192.168.3.0 is 1 hop away. Similarly, C adds 1 hop to the distance and enters the route to 192.168.3.0 into its own routing table which becomes (192.168.3.0; 2; S1).

When a computer needs to send a packet to another subnet, it sends the packet to its default gateway, which is also known as the default router.

With the network performance issues being addressed through a restructuring and the implementation of specific VLANs the routers themselves can be optimized by the removal of the current, singular routing table which has grown so complex with a Virtual Routing & Forwarding (VRF) instance which permits several routing tables to exist at any one time, all of which can be updated with network and boundary information and therefore remove the current performance issue on router CPU utilization as well as providing a further element of a scalable network.

There are two types of Internet Protocol (IP) traffic, such as Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). Some of the features that UDP possesses that are not provided by TCP/IP. First, UDP is a connectionless protocol (No handshake), which means packets sent from one node to another without making sure whether any packet may be lost during the transfer. TCP, on the other hand, makes sure to establish a connection in order to send the packets from one node to another without losing any packets. It is also known as handshake process, where nodes synchronize (SYN),

The transport layer: This layer determines how the packets are transported such as the order and what to do if there are errors. The purpose of this layer is to make sure the data be transported correctly. Besides, due to the limitation of physic (maximum IP packet size is 65535bits), the speed of transportation is limited. As a result, this layer needs break big data in to small packets. This can also collect small data into a big packet to reduce unnecessary transmission, which can improve the transmitting speed. Example protocols are TCP, UDP, SCTP.

Router devices have become popular in the networking world today. Routers are devices that forward data packets along networks. Often, they are used for small to medium networks, and overall prove efficient for users. Routers are now considered vital to the internet as well as many home and small business networks. The Internet is one of the 20th century 's best developments because it allows people worldwide to conduct e-mails and communicate back and forth in a timely manner, view web pages, make purchases, view videos, have live chat, and keep up to date with certain people on web pages such as Facebook. The internet is now considered a means of communication. Many people are all so accustomed to a computer

#include <iostream> #include <fstream> #include <sstream> #include <cstdlib> #include <string> #include <cstring> #include <list> #include <queue> #include <climits> #include <functional> #include <vector> #include <cmath> #define MAX_N 150 #define INFINITE 1000 using namespace std; //Structure of router struct router { int router_id; //int inp_q[]; //int out_q[]; int table; float dist; int prev; }; struct router* routerinfo; //Structure for Link elements struct link { int link_id; int node1; int node2; float bandwidth; float prop_delay; }; struct link* linkinfo; //Structure of Packet that is created struct packet { int num; double size; int src; int dest; }; struct packet* packetinfo; //To implement Depth first Search class Network { int N; list<int> *adj; void DFSUtil(int n, bool visited[]); public: Network(int N); void addlink(int n, int w); void DFS(); }; Network :: Network(int N) { this->N = N; adj = new list<int>[N]; } void Network :: addlink(int n, int w) { adj[n].push_back(w); } void Network :: DFSUtil(int n, bool visited[]) { visited[n] = true; cout << n <<" "; list< int>::iterator i; for( i = adj[n].begin(); i!= adj[n].end(); ++i) if(!visited[*i]) DFSUtil(*i, visited); } void Network :: DFS() { bool *visited = new bool[N]; for (int i=0; i < N; i++) visited[i] = false; for(int i=0; i < N; i++) if(visited[i]==false)