...By: Dick Gilbert Routers A router is a network layer device responsible for routing traffic between subnetwork that make up a data internetwork . A subnetwork is defined as a collection of network resources that can be reached without needing to go through a router. A internetwork a collection of two or more subnetworks connected using routers. The role of a router is pretty simple. It receives packets transmitted by end stations and routes them through the internetwork to the right subnetwork. Routers can also perform more advanced functions if the network layer protocol supports those functions. Most of them have the ability to fragment packets. Routers also provide some congestion control capablilties .Routers can be fairly sophisticated packet filters. Some people sometimes mistake routing for bridging. Routing is also a network layer function. Routers operate on packets and choices based on the network layer address. Bridging is a data link layer function. Bridges operate on frames and make filtering and forwarding choices based on the media access control address. Packets ride within frames and are the transmission unit used to get a message from one end station to another anywhere in the internetwork. If two end stations are in the same subnetwork , the packet will be placed in a frame by the transmitter and sent across the subnetwork to the...
Words: 369 - Pages: 2
...address duplex auto speed auto shutdown ! interface Serial0/0/0 ip address 192.168.10.1 255.255.255.252 clock rate 64000 ! interface Serial0/0/1 ip address 192.168.10.5 255.255.255.252 ! interface Serial0/1/0 no ip address clock rate 2000000 shutdown ! interface Vlan1 no ip address shutdown ! ip classless ! ip flow-export version 9 ! ! ! ! ! ! ! line con 0 password cisco login ! line aux 0 ! line vty 0 4 password cisco login ! ! ! end R1#conf t Enter configuration commands, one per line. End with CNTL/Z. R1(config)#router ospf 10 R1(config-router)#network 192.168.10.0\ ^ % Invalid input detected at '^' marker. R1(config-router)#network 192.168.10.1 % Incomplete command. R1(config-router)#network 192.168.10.0.0.0.3 area 0 ^ % Invalid input detected at '^' marker. R1(config-router)#network 192.168.10.0.0.0.0.3 area 0 ^ % Invalid input detected at '^' marker. R1(config-router)#network 192.168.10 0.0.0.0.3 area...
Words: 2242 - Pages: 9
...Corporate Routers Cisco Cisco has been providing routing equipment since the early 1990's. Over the years they have developed routers that met the needs of every day users to large enterprises. Cisco offers a solid product that is continuously being upgraded to meet today's trends. They have the financial stability to keep bringing these new competitive products to the market as time and products progress. Cisco's strategy is to "build, partner, and acquire". (Cisco) As noted on their website, they have "one of the largest research and development budgets of any technology firm (more than $4 billion). (Cisco) It's also noted that their first patent, which was obtained in 1992, was "for its method and apparatus for routing communication among computer networks". (Cisco) Cisco works to develop products that can be used in any medium. They believe in bringing the best options for speed, security and "maximum configuration flexibility and scalability for the most demanding networking environments". (Cisco) According to Gigaom.com, Cisco's market share has been declining over the past few years. It's two largest competitors being Juniper and Alcatel-Lucent. Even though their numbers have declined they still "43 percent...of the carrier edge routing market". (Gigaom, 2010) Juniper Last year Juniper set the tone for how it expects the future of its company to progress at Juniper's J-Partner Summit. The emphasized their strong dedication to networking as its primary...
Words: 591 - Pages: 3
...Bosack found a way to connect the two local area networks where he and his wife worked, 500 yards across campus. ! They initially tried to sell the inter networking technology that Bosack had developed to computer companies, but none were interested. With no buyers they decided top start their own company, Cisco Systems. ! Cisco’s primary product from the beginning was the inter networking router; a hardware device incorporating software that automatically selects the most effective route for data to flow between networks. Cisco thus became the first company to provide a multi-protocol router when it shipped its first product in 1986. One year later after initial start, Cisco was selling $250,000 worth of routers per month. Sales for the fiscal year ending July 1987 were 1.5 million, and the company had only eight employees at the time. ! In the beginning, Cisco marketed its routers to universities, research centers, the aerospace industry, and government facilities by contacting computer scientists and engineers via ARPANET. In 1988 the company began to target its internetworking routers to mainstream corporations with offices in multiple locations that used different networks. ! Cisco had a high rate of sales growth in the early years, however they were increasing in need of cash if they were going to continue to grow. Bosack and Lerner were forced to turn to a venture capitalist. They turned to Donald T. Valentine of Sequoia Capital, however, he required them to surrender...
Words: 1459 - Pages: 6
...NT2640 Cisco Routers Richard P Walsh 11/24/2015 Cisco routers come in various series and models. Each series and model has different purposes and performance levels for the tasks required of them. For the purpose of this report, I chose 1 model from the 3 main series. The first is the Cisco 1861, then the Cisco 2811, & finally the Cisco 3845 The Cisco 1861 is an Integrated Service Router, that has an integrated, managed Ethernet switch, and has eight 10/100 PoE ports. It is an All-in-One unified communications solution, which integrates voice, data, security, and video into one platform. The Cisco 1861 can be easily expanded by attaching a Cisco recommended Catalyst Portfolio of switches. The Cisco 1861 eliminates the cost of adding multiple servers and provides a lower price solution that is easy to set up and manage. Cisco IOS Software security feature is also an option that can be activated with hardware-based encryption on the motherboard and provides a variety of security features such as a Firewall, IP Security, and an Advanced Encryption Standard, just to name a few. This router is highly recommended for SBMs and small branch enterprises consisting of eight to fifteen employees. Some of the specifications are; DRAM * Cisco IOS Software – 256 MB * Voice Messaging – 512 MB Compact Flash Memory * Cisco IOS Software – 128 MB * Voice Messaging – 1 GB, Compact Flash Onboard Ethernet Ports * 1 10/100 Fast Ethernet * 8 10/100-Mbps LAN ...
Words: 561 - Pages: 3
...Switches, Routers, and Gateways Switches, routers and gateways are an essential part in a network. They all have the same basic functions, as they help control the flow of information between points on a network. It is important to know how each one in the flow of information. A router is common to many, especially in home networks. While connecting two or more networks, routers can do this whether these networks have the same or even different data link protocols, but the same network protocol. One advantage that a router has is that a router is capable of choosing the best route for the flow of information between networks, even if there are several possible routes. This is a result of the router knowing its own location within the network along with the packets final destination. The routing table, used by the router, identifies the best path. Another distinct advantage of a router is that it only deals with messages that are directly addressed to it. You will find that routers work on the Network Layer. Operating at the network layer, Gateways process messages using the network layer address. Interfacing between two or more dissimilar networks is what makes gateways more complex than routers. Although it’s usually different, Gateways do connect two or more networks that use different or the same data link and network protocols. This is accomplished by connecting with the same or even different kinds of cables. Gateways have also been known to operate on the...
Words: 345 - Pages: 2
...Router is small physical device that joins multiple networks together and operates at the network layer of the OSI model. A sophisticated small box-like pieces of equipment that multiple computers can connect to with each features a number of ports at the front or back that provide the connection points for these computers, a connection for electric power, and a number of LED lights to display device status. Though router and switches all share similar physical appearance, router differs substantially in their inner workings. A router is designed to join multiple area networks (LANs and WANs). On the Internet or on a large corporate network, it serves as intermediate destinations for network traffic. A router receives TCP/IP packets, checks it out to identify the source and target IP addresses, then forward the packet its intended destination. A router for home networks (called broadband) also can join multiple networks and designed specifically to join the home (LAN) to the Internet (WAN) for the purpose of Internet connection sharing. In addition, a broadband router contains several features beyond those of a traditional router. A broadband router provides DHCP server and proxy support and offers integrated firewalls. A wired Ethernet broadband router typically incorporates a built-in Ethernet switch that allows several hubs or switches to be connected to them, as a means to expand the local network to accommodate more Ethernet devices. A Network switch is a small hardware...
Words: 378 - Pages: 2
...Unit 3 Labs Lab 9: Setting Router Passwords Step 4. Configure the router to require a password of ciscopress when connecting through the console. To do so, start by issuing the line con 0 configuration command, which moves you to console line configuration mode. What does the command prompt look like after using this command? The command line now says: Router(config-line)# Step 11. Press Enter. Does the router prompt you for a password? Does the password ciscopress work? Yes and yes Step 12. Use the enable command to move from user mode to enable mode. Which of the two passwords (fred or barney) works? Which configuration command did you use to con- figure that password? Barney was the password that worked, and enable secret barney Lab 10: Configuring Router IP Settings Step 4. Use the show ip interface brief command to view all interfaces. Which interfaces have an IP address configured? What are the addresses and the corresponding masks? None of the interfaces have an IP address configured Step 10. Use the show ip interface brief command to view all interfaces. Is the router’s Fa0/0 IP address now listed? What is the IP address? Yes the IP address is now listed. The IP address is 10.1.1.4 Step 11. Confirm that R1’s Fa0/0 interface is working by pinging PC1 (10.1.1.1). Did the command output imply that R1 can send packets to and from PC1? Yes it implies that R1 can send packets Lab 22: Terminal History Step 5. Press Up Arrow again to bring up...
Words: 898 - Pages: 4
...Justin Iler NT1210 Final Paper Routers vs. Layer 3 Switches You ask if a layer 3 switch can replace a router and I will yes you can. A layer 3 switch is actually faster than a router. The router receives a packet and then looks to the switch to see where to send it whereas the switch will receive the packet process the packet itself and then send it on. The pattern matching and caching on a layer 3 switch is similar to a router. They both use routing protocol and routing table to determine the best path. But, a Layer 3 switch has the ability to reprogram the hardware dynamically with the current Layer 3 routing information. This always the layer 3 to process the packet faster. Also, on layer 3 switches the information received from the routing protocols is used to update the hardware caching tables. I believe a difference for now is that the router is used primarily on the WAN and the switches are used on the LAN. That’s not to say that you can’t use a Layer 3 on a WAN. Another difference is the cost. The router is much more expensive than the layer 3 switch. For example, a Catalyst 3550-24 EMI switch sets you back $4,990 U.S. list, which provides a packet forwarding rate of 6.6 million packets per second with 24 * 10/100BASE-T ports and 2 * 1000BASE-X ports. A Cisco 7300 router with an NSE-100 engine provides a packet forwarding rate of 3.5 million packets per second, but sets you back $22,000 U.S. list and has only 2 * 1000BASE-T ports in its base configuration. Also...
Words: 347 - Pages: 2
...Lab #1 – Assessment Worksheet Cisco Router Hardware & Software Discovery 1. What Cisco “show” command displays various information and details about the router or switch such as Model #, flash memory, RAM, IOS version and physical interfaces? Show Version 2. During the Instructor’s TELNET session to LAN Switch 1 and LAN Switch 2 – what was the captured terminal password for LAN Switch 1 and LAN Switch 2? Cisco 3. What is the size of the IOS file used for the Cisco 28xx Routers? 239Kb 4. What is the command used to enter the global configuration mode for interfaces on a Cisco Router or Switch? Router>enable 5. The default hexadecimal value of the configuration register setting for the Cisco 28xx Router is? 0x2102 6. What are the specific settings for the configuration hexadecimal value 0x2102? -ignores break -boots into ROM if initial boot fails -9600 console baud rate default value for most platforms 7. What is the key sequence used to interrupt the boot sequence of a router and initiate the password recovery sequence? Pause/Break key on the keyboard 8. Using the password recovery process how can you break the router boot sequence to see the router saved passwords and what can you do in that mode. Ctrl – C to skip to the initial setup procedure to view, change and delete passwords 9. What is the command used to back up the running-config file to TFTP? “copy running – config TFTP” 10. What process takes place...
Words: 277 - Pages: 2
...Cisco E4200 Router Configuration Network Address Translation Network Address Translation (NAT) is used to convert internal IP addresses into public IP addresses. This allows multiple devices on our customer’s networks to access the internet through one of public IP addresses provided by their internet service provider. The following steps will walk you through configuring the Cisco E4200 Router to perform NAT from the web browser based utility page. 1. Click the Advance Routing link in the Setup menu. 2. Click the Enabled radio button on the NAT line to activate NAT and click the Save Settings button at the bottom of the page. Packet Filtering Configuring our client’s router to conduct packet filtering will add an additional layer of security for their network. Advanced packet filtering is conducted by creating rules that either allow or reject incoming traffic based on protocol type and port number. The Cisco E4200 comes with pre-configured rules that conduct very general packet inspection. The following steps will outline how to configure the Cisco E4200 Router to perform packet filtering from the web browser based utility page. 1. Click the Security link from the menu. 2. Click the Enabled radio buttons for IPv4 and IPv6 SPI Firewall Protection. Default Gateway Installing a router for our customers will make it their Default Gateway to their ISP. A default Gateway is used to route internet traffic to and from the hosts on the network...
Words: 332 - Pages: 2
...D Case Project 6-1 A router forwards data packets by performing "traffic direction" functions between two more separate networks and/or between different computers on the same network. You can use the ipconfig command to get host computer configuration information, including the IP address, mac address, your adapter info and router or switch info, subnet mask, and default gateway. the tracert command can be used to check the path to the destination IP address that you want to reach. The tracert command displays the series of IP routers that are used in delivering packets from your computer to the destination and how long it took on each hop. If the packets are unable to be delivered to the destination, the tracert command displays the last router that successfully forwarded your packets. To get more detailed information about throughput rates and to determine what the physical topology is you need to be able to access the equipment and telco rooms because there might be some hidden problems. Like the equipment may not be compatible causing errors on the network and the cables, ports on connectivity devices, and data jacks have to be labeled and according to TIA/EIA standards. Case Project 6-2 The telcom room is located on the 1st floor of the Connect Spree and there are 4 internal servers, Internet Service and 4 routers inside the telcom room. Black solid line shows the connection of 4 internal servers to routers and the connection of 4 routers with each other. Red solid...
Words: 968 - Pages: 4
...1. The machine that wants to send out the packet will know the IP address of the destination. It checks the routing table it has to find out which router within its network can send the packet out on its behalf. 2. Based on the IP address of the router, the machine chooses the right network interface card (NIC) that is able to communicate with that router. It then sends the packet to the that NIC, after adding the Layer 2 protocol data to the packet (which should have the MAC address of the router). 3. The NIC should be connected to a switch and sends out the packet to the switch using the Layer 1 protocol to convert the packet into electrical signals that can be sent over the wire. 4. The switch reads the MAC address of the router...
Words: 437 - Pages: 2
...that host. If multiple hosts are having problems, verify the default gateway setting, and verify that the DHCP server is configured to deliver the correct default gateway address. If all hosts have the same problem, and if the default gateway setting is correct, verify that the default gateway server is up and configured for routing. If hosts are unable to contact hosts on a specific subnet, but communication with other subnets is working, check the following: Verify that the router connected to the subnet is up. Use the route command on the default gateway of the local subnet and verify that the router has a route to the remote subnet. If necessary, configure a static route or a routing protocol so that the route can be learned automatically. Use traceroute to view the route taken to the destination network. Identify the last router in the path, then troubleshoot routing at that point. Check for routing loops in the path to the destination network. A routing loop is caused by a misconfiguration in the routers along the path such that data is sent back along the same path rather than being forwarded to the destination. Routing loops are indicated by: Routing table entries that appear and then disappear (called route flapping), often at regular intervals (such as every minute). Routing table entries where the next...
Words: 845 - Pages: 4
...ABSTRACT—SpaceWire is a real-time communications network for use onboard spacecraft. It has been designed to connect together sensors, mass-memories, processing units, and downlink telemetry sub-systems onboard a spacecraft into a lightweight, high-performance data-handling network. This paper provides an introduction to SpaceWire and the SpaceWire standard. It describes the key features of SpaceWire. The many current and planned space missions that are using or plan to use SpaceWire for onboard data-handling are also introduced I. INTRODUCTION SpaceWire is a communications network for use onboard spacecraft. It is designed to connect high data-rate sensors, large solid-state memories, processing units and the downlink telemetry subsystem providing an integrated onboard, data-handling network. SpaceWire links are serial, high-speed (2 Mbits/sec to more than 200 Mbits/sec), bi-directional, full-duplex, point-to-point data links which connect together SpaceWire equipment. Application information is sent along a SpaceWire link in discrete packets. Control and time information can also be sent along SpaceWire links. SpaceWire is defined in the European Cooperation for Space Standardization ECSS-E50-12A standard. SpaceWire is based on the “DS-DE” part of the IEEE-1355 standard combined with the TIA/EIA-644 and IEEE-1596.3 Low Voltage Differential Signaling (LVDS) standards. Several problems with IEEE-1355 have been solved in the SpaceWire standard and connectors and cables...
Words: 3798 - Pages: 16
