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Local Area Network
Questions concerning the setting up, troubleshooting and operation of wired LANs used by businesses and other organizations
4,003 Questions
Peer editing is having someone in your group (school class, for example) look over your work and make comments and suggestions. This gives you the opportunity to fix things before having to turn in the version that counts.
What is the advantage of using telnet in router configuration?
The main advantage of using this is remote access on the network.
How does email move within a local area network?
Email within a local area network operates nearly the same as it does on the Internet without traveling across multiple networks. An email sent is delivered using an SMTP (Simple Mail Transfer Protocol) server which sends it to the appropriate mailbox, and the user receives the email from connecting to their POP server.
Why is my computers sending but not receiving data to my lan?
In most cases the reason is Windows firewall. Check settings in Control panel. Also the computer you are trying to connect to might accept network connections.
What is the color code of straight cable and cross cable?
The pairs designated for 10BaseT Ethernet are orange and green. The other two pairs, brown and blue, are unused. The connections shown are specifically for an RJ45 plug. The wall jack may be wired in a different sequence because the wires may be crossed inside the jack. The jack should either come with a wiring diagram or at least designate pin numbers that you can match up to the color code below.
There are two wiring standards for these cables, called T-568A and T-568B. They differ only in pin assignments, not in uses of the various colors. The illustration above shows both standards. With the T-568B specification the orange and green pairs are located on pins 1, 2 and 3, 6 respectively. The T-568A specification reverses the orange and green connections, so that the blue and orange pairs are on the center 4 pins, which makes it more compatible with the telco voice connections.
T-568A is supposed to be the standard for new installations, and T-568B is the alternative. However, most off-the-shelf data equipment and cables seem to be wired to T568B.
Pin Number DesignationsHere are the pin number designations for both standards: T-568BPin Color Pair Descrtipion1 white/orange 2 TxData +2 orange
TxData -
RecvData +
blue 1 Unused
white/blue 1 Unused 6 green 3 RecvData -
7 white/brown 4 Unused
8 brown 4 Unused
T-568APin Color Pair Description1 white/green 3 RecvData +2 green 3 RecvData -
3 white/orange 2 TxData +
4 blue 1 Unused
5 white/blue 1 Unused
6 orange 2 TxData -
7 white/brown 4 Unused
8 brown 4 Unused
Note: Odd pin numbers are always the striped wires..
Straight-Through vs Cross-OverIn general, the patch cords that you use with your Ethernet connections are "straight-through", which means that pin 1 of the plug on one end is connected to pin 1 of the plug on the other end (for either standard). The only time you cross connections in 10BaseT is when you connect two Ethernet devices directly together without a hub or connect two hubs together. Then you need a "cross-over" patch cable, which crosses the transmit and receive pairs. An easy way remember how to make a cross-over cable is to wire one end with the T-568A standard and the other with the T-568B standard.Termination
UTP cables are terminated with standard connectors, jacks and punchdowns. The jack/plug is often referred to as a "RJ-45", but that's a telco designation for the "modular 8 pin connector" terminated with a USOC pinout used for telephones. The male connector on the end of a patchcord is called a "plug" and the receptacle on the wall outlet is a "jack."
In LANs, as spec'ed by 568, there are two possible pinouts, called T568A and T568B, that differ only in which color coded pairs are connected - pair 2 and 3 are reversed. Either work equally well, as long as you don't mix them! If you always use only one version, you're OK, but if you mix A and B in a cable run, you will get crossed pairs!
The cable pairs are color coded as
Pair 1 is white-blue/blue,
Pair 2 white-orange/orange,
Pair 3 is white-green/green
Pair 4 is white-brown/brown.
Jacks usually have punchdowns on the back or can be terminated without punchdowns using special manufacturer's tools or even a cover for the connector. Again, you MUST keep the twists as close to the receptacle as possible to minimize crosstalk.
Note that Cat 3 jacks and all plugs are going to use these color codes. However, Cat 5 jacks have internal connections that continue the twists as close to the pins in the jacks as possible. Thus the pinout on the back of the jacks will not usually follow these layouts! Always follow the color codes on the back of the jacks to insure proper connections!
Crossover Cables:
Normal cables that connect a PC/NIC card to a hub are wired straight through. That is pin 1 is connected to pin 1, pin 2 to pin 2, etc. However, if you are simply connecting two PCs together without a hub, you need to use a crossover cable made by reversing pair 2 and 3 in the cable, the two pairs used for transmission by Ethernet. The easy way to make a crossover cable is to make one end to T568A color coding and the other end to T568B. Then the pairs will be reversed.
Punchdowns:
Punchdowns come in 4 varieties: 110, 66, Bix and Krone. Most popular for LANs is the 110 (on the left), for telcos it's the 66 (on the right), and the Bix and Krone are rare (price, proprietary designs, etc.)
110 block 66 block
Color Codes For Punchdowns:
Punchdowns of all types are always made with the pairs in order with the white/stripe wire first, then the colored wire, Pair 1(w/blue-blue), Pair 2 (w/orange-orange), Pair 3 (w/green-green), Pair 4 (w/brown-brown). (This color code is remembered by BLOG - BLueOrangeGreen and brown)
What is the best heavy duty network printer?
Since nobody else is answering I will. My experience with actual network printers is limited to installing them for medium sized networks (50-100 comps)... just keep that in mind. I have found that HP are fairly good and I dont get any real complaints. I have had a few bad experiences with Canon so I wouldn't be in a hurry to go back there again. Personally Id be looking for a HP.
To my experience, stay away from Canon (they really... CAN'T!). Bad quality colour printers those are and they cannot hold the quality for a medium time (never mind long!). B&W is fine, but be careful. Those machines (5800/6800) do not last the distance without breaking down...
What are the maximum upstream and downstream transfer rate for DSL and cable connections?
Cable systems provide rates of approximately 500 Kbps downstream and 128 Kbps upstream. Theoretically they can provide a bandwidth of 30 Mbps. A DSL system can provide speeds of up to 7.1 Mbps, but most providers offer a maximum of 1.5 Mbps upstream and downstream.
First you need to turn 256kbytes in to bit so * 8 = 2048 kbit then you need to turn it in to gbits so divide by 1024 to get mbits 2 then divide by 1024 to gbits = 0.002gbits
then divide 0.002 gbits by the 1 gigbit = 0.002 secounds
Which network topology is secure?
Mesh topology is the most secure topology bcoz in mesh topology each device has a dedicated link to others .
A bridge typically creates separate collision domains within the same broadcast domain. If you take a bridge with 2 ports, each port connects to a LAN segment that is in its own collision domain.
Therefore, for a 2 port bridge you will get 2 different collision domains.
What is the function of DNS service on a tcp ip network?
DNS service is responsible for converting names in IP addresses. When type in your browser google.com DNS server will convert it appropriate IP address so you can access services provided by Google.
What is the purpose of collision domain and how does it work in a ethernet network?
There is no purpose. It is rather unfortunate downside. In early years of networking networks were not capable of full duplex as result admins had to deal with collision domains.
Problem of collision domains does not exist in modern equipment because data sent and received on different pairs of wires.
There are exceptions but they are not applicable to the most of situations admins have to deal with.
Using tie wraps for cat5 cables?
You can use tie wraps for Cat-5 cabling. Just be sure not to overtighten the tie wraps, though.
How does TCP implement reliability?
The main task of the Transmission Control Protocol is simple: packaging and sending data. Of course, almost every protocol packages and sends data. What distinguishes TCP from these protocols is the sliding window mechanism that controls the flow of data between devices. This system not only manages the basic data transfer process, it is also used to ensure that data is sent reliably, and also to manage the flow of data between devices to ensure that data is transferred efficiently without either device sending data faster than the other can receive it.
Which Layer 1 devices can be used to enlarge the area covered by a single LAN segment?
hub is the device that is used to extend the lan segment and used at layer1 that is physical layer.
rtd .3 sender digram
Features of high speed multiservice network?
Two features of a high speed multiservice network are versatility and modularity. Its primary components are teleport, transportation network and clusters.
The DHCP server will not issue the addresses ranging from 192.168.24.1 to 192.168.24.5.
DDoS stands for Distributed Denial of Service.
It’s a type of cyberattack where multiple compromised devices are used together to flood a target system, network, or website with traffic, making it slow or unavailable to real users.
OSI stand s for open system interconnection. It is a networking model given by ISO. It is introduced so that systems can communicate with each other regardless of their underlying architecture.
How do you create workgroup for 5 comps in same room all hooked to a switch then to modem for DSL?
win+Pause->Computer Name->Change. After you have changed the workgroup name you will have to restart your PC(s) to make it's working.
What is the difference between the router and gateway?
The main difference between a router and a gateway is in their functionality in a network. A router will be connected to two different networks and will transmit packets between them. As for the gateway, it will link different networks using varied protocols.
What are the different types of server hardware?
Types of server hardware are:
- Application server, a server dedicated to running certain software applications
- Catalog server, a central search point for information across a distributed network
- Communications server, carrier-grade computing platform for communications networks
- Compute server, a server intended for intensive (esp. scientific) computations
- Database server, provides database services to other computer programs or computers
- Fax server, provides fax services for clients
- File server, provides remote access to files
- Game server, a server that video game clients connect to in order to play online together
- Home server, a server for the home
- Mail server, handles transport of and access to email
- Mobile Server, or Server on the Go is an Intel Xeon processor based server class laptop form factor computer.
- Name server or DNS
- Print server, provides printer services
- Proxy server, acts as an intermediary for requests from clients seeking resources from other servers
- Sound server, provides multimedia broadcasting, streaming.
- Stand-alone server, a server on a Windows network that neither belongs to nor governs a Windows domain
- Web server, a server that HTTP clients connect to in order to send commands and receive responses along with data contents
For information about the servers, visit the Related Link.
