Cisco Systems, Inc. is a major IT company, which produces networking equipment and network management solutions for both personal and commercial use. Questions about this company and its products belong here.

3,144 Questions

Where can I find free CCNA online exam dumps?

You can Google for this information, but I don't recommend using a braindump site; the answers are very often incorrect, since it is based on the memory recollection of someone who took the exam, and the answers have not been checked for accuracy.

Furthermore, the use of such material goes against the user agreement that you sign when you sit for an exam.

Is a VLAN essentially a collision domain?

No- A VLAN is a single broadcast domain. If the VLAN uses a hub, which essentially connects all devices on a single wire, the the VlAN would be a collision domain. However hubs are rarely seen these days. A network switch keeps every device separated on individual collision domains so every device is kept from colliding with any other device.

What is the importance of the OSI model?

The OSI model is a theoretical model of how protocols and standards should work together for a common understanding of network communications. It describes what happens when one packet goes from one device to another. Without the model we would not have an understanding of how to connect networks together.

A network engineer needs a very good understanding of the model and the responsibilities of each layer of the model.

Does the Cisco WS-C3550-24-SMI support 802.3af PoE?

No, the WS-C3550-24-SMI will not support PoE of any type.

Why is the transport layer not present inside the network?

The transport layer provides additional function to compensate for the limitations and impairments of the network layer, in order to meet requirements (e.g. QoS) of the upper layer. For example in TCP/IP, IP provides only best effort service. To provide the reliable service required by some applications - that is, to compensate for the shortcomings of best effort service - TCP establishes connections and implements flow control and congestion control on an end-to-end basis. Answer Actually, it is, just not through normal tools. Special programming is required to access the upper layers of TCP.

What is the difference between router and switch?

Router is a layer 3 and switch is a layer 2 device.

Router connects many networks together and Switch connects many devices to a network.

Uses of computer in business?

computers can be used in business from the stage of manufacturing till the stage of its sale. we cant think of a business without a computer. business is all around of computers. a manager's work is depends on computer scheduling controlling communication managing data and all the information about company and competitors.Computers can keep records of all the employees and prepare their pay cheques in a fraction of minutes every month.A computer can easily carry out automatic checks on the stock of a particular item.

What is the router static routes cisco 6.8.1?

for R1-ISP

network -

mask -

next hop - (R2's S/0/0/0 IP Address)

for R2-Central

network -

mask -

next hop - (R1's S/0/0/0 IP Address)

Your R2-Central is right but your R1-ISP is wrong Sir!

correct R1-ISP

network -

mask -

next hop -

What are the functional areas of IT organizations?

The purpose of functional areas is to ensure all important business activities are carried out efficiently. This is essential if the business is to ever achieve its aims or objectives. Administration is a support required by all businesses. Senior Administrators carry out a wide range of tasks. The main task of an administrator is to keep the business running smoothly. Bad administration could ruin a company's image. Administration would include these areas: · Planning is deciding in advance what to do, how to do it, when to do it, and who should do it.· Organizing involves identifying responsibilities to be used, grouping tasks into departments or division. Customer Service is what deal with all the complaints enquiries and concerns. Today customers only expect the best. With bad customer service it will give the competitor the edge in that field no one expects to be treated badly by a company so why should they be. Distribution (Deliveries/Transport) is ensuring that the package is delivered to the customer on time and in the right condition. Some companies such as Amazon just deliver so they rely hugely on the Distribution department. Whereas some companies such as BNQ rely on the stock coming to them into their superstores from the regional warehouses. Distribution is the middle of the process how the goods get to the consumer. Finance a lot of entrepreneurs considers this to be the most important department in any business. This is because all companies must have a regular money income to survive. Finance will handle some of the company's most important decision. Human Resources of a business are its employees. Organisation should look after their staff and make sure that the staff is trained and committed to the aims of the business, the organisation is healthier and therefore more chance of being successful. HR is responsible for recruiting new staff. Sometimes companies have an induction scheme which helps find the best people for the job. ICT function is having at least one person who understands ICT and what to if it goes wrong. This is vital in any kind of company small, medium, big. A problem is a problem. Most large organisation has a computer network and need staff to maintain the network or it could find the company slopping. The website is probably technically run by the ICT specialists. Marketing is all about indentifying the customer's and meeting their customer's needs. They find out what product the public is interested in, what price they are willing to pay inform and promote the products and how the organisation should distribute them for example through the internet, in a shop etc. Sales are a vital function in any business. It is pointless having superb products and services if no one buys them. Meeting the aims and objectives are the responsibility of the sales team. Sales are the keystone to any business. Production refers to the manufacture or assembly of the goods. The standard always has to be high for any customer or it would be a customer service issue which they will have to deal with. Research and Development is all the improvement to the equipment which the staff uses or even could be the product which they sell. They use market research and customer service.

What is the difference between IPv4 and IPv6?

IPv6 is based on IPv4, it is an evolution of IPv4. So many things that we find with IPv6 are familiar to us. The main differences are:

1.Simplified header format. IPv6 has a fixed length header, which does not include most of the options an IPv4 header can include. Even though the IPv6 header contains two 128 bit addresses (source and destination IP address) the whole header has a fixed length of 40 bytes only. This allows for faster processing.

Options are dealt with in extension headers, which are only inserted after the IPv6 header if needed. So for instance if a packet needs to be fragmented, the fragmentation header is inserted after the IPv6 header. The basic set of extension headers is defined in RFC 2460.

2.Address extended to 128 bits. This allows for hierarchical structure of the address space and provides enough addresses for almost every 'grain of sand' on the earth. Important for security and new services/devices that will need multiple IP addresses and/or permanent connectivity.

3.A lot of the new IPv6 functionality is built into ICMPv6 such as Neighbor Discovery, Autoconfiguration, Multicast Listener Discovery, Path MTU Discovery.

4.Enhanced Security and QoS Features.


IPv4 means Internet Protocol version 4, whereas IPv6 means Internet Protocol version 6.

IPv4 is 32 bits IP address that we use commonly, it can be, or other 32 bits IP addresses. IPv4 can support up to 232 addresses, however the 32 bits IPv4 addresses are finishing to be used in near future, so IPv6 is developed as a replacement.

IPv6 is 128 bits, can support up to 2128 addresses to fulfill future needs with better security and network related features. Here are some examples of IPv6 address:




The most important difference is that it has a larger address space. IPv6 uses 128 bits, instead of the 32 bits used in an IPv4 address.

There are also some changes in the header format, and some additional options, like built-in security options. These can be added to IPv4 through additional protocols, so this is really no big deal.
IPv4 is like while IPv6 is one huge garble.
IPv4 is a 32 bits IP address that we use commonly, it can be, or other 32 bits IP addresses. IPv4 can support up to 232 addresses, however the 32 bits IPv4 addresses are finishing to be used in near future, so IPv6 is developed as a replacement.

IPv6 is 128 bits, can support up to 2128 addresses to fulfill future needs with better security and network related features.

Here are some examples of IPv6 address:




For More help, you can visit website:
The main difference, at least the one that is most relevant for a transition from version 4 to version 6, is the length of the addresses. IPv4 uses 4 bytes; IPv6 uses 16 bytes for the address.
Mainly, IPv6 has a larger addressing space; IPv6 addresses use 128 bits instead of 32 bits.

Where can you purchase Cisco equipment?

To order Cisco gear you have four options:

  • Locate a Cisco Partner
  • Purchase Through an Online Partner
  • Purchase Through WSCA
  • Order Direct From Cisco

You can find more details by visiting Cisco's website.

Whats the difference between baseband and broadband?

In Baseband, data is sent as digital signals through the media as a single channel that uses the entire bandwidth of the media. Baseband communication is bi-directional, which means that the same channel can be used to send and receive signals. In Baseband no frequency-division multiplexing is not possible. (Multiplexing (short muxing) is a process where multiple analog message signals or digital data streams are combined into one signal over a shared medium.)

Broadband sends information in the form of an analog signal. Each transmission is assigned to a portion of the bandwidth, hence multiple transmissions are possible at the same time. Broadband communication is unidirectional, so in order to send and receive, two pathways are needed. This can be accomplished either by assigning a frequency for sending and assigning a frequency for receiving along the same cable or by using two cables, one for sending and one for receiving. In broadband frequency-division multiplexing is possible

On a Cisco router what does it mean when the status is administratively up but protocol is down?

Ports on Cisco routers can be enabled or disabled by the router OS. "Administratively Up" simply means that the port has been enabled by the router's OS. If a port is enabled (Administratively Up) and the protocol is down, then there is a problem with communications over that port. Problems could one of many including; bad cable on the port, the far end device is down, the protocol configurations on the two connected device ports are not configured correctly to enable communications.

Can you use a Cisco 7921 phone with Skype?

Skype uses their own non-standard protocol, so no, you can't use Cisco or other SIP phones with it.

How do you recover the password for a cisco 2501 router?

Cisco Router Password Recovery (Method One)

Using this method can make the following cisco routers password recovery: Cisco2000 series, 2500 series, 3000 series, 680 x0MotorolaCPU, Cisco4000 series, operation version 10.0 or above the 7000 series routers CiscoIOS system.

  1. The router console mouth connected to a terminal or with installation of the software simulation terminal PC.
  2. Input showversion command, and then write down registers value, usually 0 x2102or0x102. This value displayed in the last line, pay attention to the configuration of the register whether Break set to enable or disable.The default configuration register value is 0 x2102. This value from the left number the third digital if is 1, it is disableBreak; If for zero, the Break for enabled.
  3. Cut off power supply after the restart.
  4. The router start in 60 seconds internal terminal according to Break key. Will show rommon > prompt. If this is not prompt, the terminal was given the right the interrupt signal, check Break key is correct or whether it is set to disable.
  5. In the prompt next input o/r0x42 or o/r0x41, o/r0x42 meaning from the Flashmemory guide, o/r0x41 meaning from the ROMs guide (note, the first character is the letter "o", not the number zero). The best is 0 x42, Flashmemory is not installed or erase in the case, just use 0 x41, if have 0 x41 is can only view or erase configuration, can not directly change your password.
  6. In rommon > prompt next input initialization command.
  7. Input system configuration dialog prompt knock no, waiting for that message: PressRETURNtogetstarted!
  8. Press enter, appear Router > prompt.
  9. Input enable command, appear Router# prompt.
    • Router# configurememory
    • Router# configureterminal
    • Router (config) # enablesecret1234abcd
    • Router (config) # CTRL-z
    • Router# writememory
  10. Select the option of a:
    • If no password encryption, use direct morenvram: startup-config command can see password; In the password encryption, can't see, can only alter, type the command that is as follows:
  11. In EXEC prompt input configureterminal enter configuration mode. Input config-register order to record in step 2 registers value recovery.
  12. Knock Ctrl-Z, exit the configuration state.
  13. In the privilege mode writememory with command save configuration, then reboot to restart.

Cisco Router Password Recovery (Method 2)

Using this method can make the following cisco routers password recovery: Cisco1003, series 1600, series 3600, series 4500, series 7200, series 7500 and IDTOrion-Based routers, the first step and the first method.

  1. In rommon > prompt input confreg under orders. Doyouwishtochangeconfiguration [y/n]?
  2. Input yes, then press enter. In answer to the back of the problems have been no choice, until appear "ignoresystemconfiginfo [y/n]?" When the input yes. Then continue to knock no answer, has been to see "changebootcharacteristics [y/n]?" When the input yes.
  3. Entertoboot: in this prompt can have 2 and 1 under two options. If Flashmemoryiserased choose 1, this can only vieworerase configuration, can't edit password. Had better choose 2. Appear as follows tip: Doyouwishtochangeconfiguration [y/n]? Answer no, then press enter, shows "rommon >".
  4. In the privilege under command input EXEC reload.
  5. Cisco routers password recovery operation to this, with the first method behind operation.

What is the difference between a router and a switch?

A switch sorts and distributes the network packets sent between the devices on a local area network (LAN), while a router is a gateway that connects two or more networks, which can be any combination of LANs, wide area networks (WAN), or the Internet. In addition, a router uses tables to determine the best path to use to distribute the network packets it receives, and a protocol such as ICMP to communicate with other routers. A router is a significantly more complicated device than a switch--essentially a specialized computer--and more advanced models may use a reconfigurable operating system such as Linux, rather than firmware coded directly into the hardware. Both routers and switches operate on layers 2 and 3 of the OSI model.

In an enterprise environment, routers and switches are separate physical devices dedicated to their specific tasks. However, typical "broadband routers" for the home and small office are actually multifunction devices that combine the capabilities of a router, a switch, and (usually) a firewall into one box. In addition to routing traffic between the Internet and the LAN, they also handle switching for packets between devices on the LAN, and often add additional features such as port forwarding and triggering, a DMZ, a DHCP server, a DNS proxy, and/or network address translation. In addition, "wi-fi routers" add a wireless access point.

Note: A hub is even simpler than a switch. Instead of inspecting the packets that it encounters and sending them to the correct destination device, it just forwards them to all connected devices.

In short, Router routes any traffic comes to it & Switch provides local services to local user's in LAN but some special Switches are out their that work for both LAN & WAN. They are much expensive and used by the big Organizations.

A router connects 2 separate networks (e.g. WAN and LAN)

A switch connects all network components (like computers, network printers, etc) within a network.
A switch does essentially what a hub does but more efficiently. By paying attention to the traffic that comes across it, it can "learn" where particular addresses are. For example, if it sees traffic from machine A coming in on port 2, it now knows that machine A is connected to that port and that traffic to machine A needs to only be sent to that port and not any of the others. The net result of using a switch over a hub is that most of the network traffic only goes where it needs to rather than to every port. On busy networks this can make the network significantly faster.

A router is the smartest and most complicated of the bunch. Routers come in all shapes and sizes from the small four-port broadband routers that are very popular right now to the large industrial strength devices that drive the internet itself. A simple way to think of a router is as a computer that can be programmed to understand, possibly manipulate, and route the data its being asked to handle. For example, broadband routers include the ability to "hide" computers behind a type of firewall which involves slightly modifying the packets of network traffic as they traverse the device. All routers include some kind of user interface for configuring how the router will treat traffic. The really large routers include the equivalent of a full-blown programming language to describe how they should operate as well as the ability to communicate with other routers to describe or determine the best way to get network traffic from point A to point B
Different router and different switches can all do different things. The dividing line between all these devices is getting very fine. However one major difference between a router and a switch is that a router has it's own IP address. This allows you to log into it.

Aswell as that most home routers have wireless capabilities (thats the only reason why most home users want them in the first place anyway).
Different router and different switches can all do different things. The dividing line between all these devices is getting very fine. However one major difference between a router and a switch is that a router has it's own IP address. This allows you to log into it.

Aswell as that most home routers have wireless capabilities (thats the only reason why most home users want them in the first place anyway).
Both a switch and a router will both connect multiple computers to one internet connection and also allow them to connect to each other for high speed file sharing. Routers assign computers with IP addresses and also provide some basic firewalling. Switches do not do this; they are supposed to be used to extend routers or be hooked up to a server. Routers usually only have a maximum of four ports while switch can have up to 32 or more.

What method to Restricting users in wireless LAN?

One type of restriction is to use MAC filtering in the WAP. Another would be to secure the wireless network via WEP/WPA/WPA2 security which would require other users to have the key to connect.

Ccna discovery 2 final exam answers?

51A user in a small office is unable to connect to the Internet. The user examines the physical connections to the ISR, a Linksys WRT300N, and notices a solid green LED on the port that is wired to the computer. What does the LED indicate about the current state of the port?

What is a local digital loop back?

A local digital loopback is a test that is performed to check the transmitter and receiver of a local modem, or being simpler, it's a test that sends a signal to a remote receiver and waits for the signal to be returned.