0
Local Area Network
Questions concerning the setting up, troubleshooting and operation of wired LANs used by businesses and other organizations
4,003 Questions
competetive access provider
What best describes the operation of distance vector routing protocols?
They send their routing tables to directly connected neighbors.
What is the name of the jack the CAT 5 plugs into?
The form factor is RJ-45. However, RJ-45 is not necessarily CAT-5; many RJ-45 jacks are intended for phone use and only spec to CAT3 or even less. Typically, the jack that CAT5 plugs into is called a CAT5 jack, to differentiate it from the CAT3 RJ-45.
Disadvantages of computer telephony integration?
For example: land line telephones are very simple, reliable and inexpensive devices, while computers and internet connections are not.
How do you outsource computer work?
It is recommended to ask your business associates for a referral. If that doesn't work, check one of the great freelance sites such as Guru.com or eLance.com. They have thousands of service providers that can offer everything from simple Web design to dealing with more complex programming issues. I have used both sites with great success. Look before you leap.
If you do plan to outsource an IT activity, you need to ensure that you clearly understand what you want to achieve. Even for simple jobs like graphic design, ensure that you have a project plan, and a set of requirements that describe in detail what the outsourcer will be doing.
If you don't have these things a project can get out of control very quickly, wasting your time and money.
What are the objectives of the DNS name resolution project?
Quoting the Windows Server 2008 Administrator Microsoft Official Academic Course:
The objectives of the name resolution project were as follows:
- To create a means for administrators to assign host names to their computers without duplicating the names of other systems
- To store the host names in a database that would be accessible by any system, anywhere on the network
- To distribute the host name database among servers all over the network
- To avoid creating traffic bottlenecks and a single point of failure
- To create a standardized system for host naming accessing electronic mailboxes
- To allow name changes to be dynamically updated to all participating computers
What subnet mask is used for 192.168.12.526?
It depends on whether you are subnetting or not. If not, the default subnet mask would be 255.255.255.0
With TCP IP data encapsulation which range of port numbers identifies all well known applications?
The well-known or reserved ports are ports 0 - 1023.
What is Quality of service in tcp ip?
Quality of Service (QoS) is a technique to manage how well the network is performing. It uses service metrics to figure out where problems and bottlenecks might be in a network and measures transmission times, re-transmits, and other measurable qualities in a network.
There are some protocols and networks that require a high degree of functioning, and the way to tell whether or not the network is functioning properly is by sampling what the network is doing. This is the purpose of QoS.
Which man page section refers to system calls?
There are several 'man' sections for system calls. The basic system calls for the C api are in section 2, which is pretty much the default. Others may be in 3C, 3S, etc., depending on the type of functionality they have. For example, a lot of the string related functions are in 3S.
Anything that has an admin type of API requirement might be in sections 5 and 8, or 8m, etc., depending on the OS type.
The Virtual Switching is a technology allowing multiple switching functions to happen in one physical device or single functional switching to happen in multiple physical devices across network, while in the situation of a real switch, switching is conducted in one physical switch. Virtual switching technology enables a single switch to be used for many different applications. Each different function may have its own discrete performance and security controls. Using virtual switching technology, Service providers can create a dynamic service mix, as desired, without requiring new hardware and enabling the gradual evolution to include new services or a common control plane. Virtual switching is a core concept in the Multiservice network switching architecture.
How i should make crossover cable?
I am assuming you have bulk cable available, RJ-45 connectors and a crimping tool. Wire one end of the cable using the T568-A wiring standard, and the other using T568-B. That's your crossover cable.
What is the interpolation method in computer?
Interpolation tries to predict where something should be based on previous data, movements or a theory.
These hidden addresses can be used many times in many different organizations. This way different organizations can use the same address range and not collide with other networks.
Given the ip address and subnet mask of 172.16.134.64 is subnet mask 255.255.255.224 valid?
This is a network address
What is the difference between a router and 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.
Two
What is a stand-alone desktop computer considered?
Since a stand-alone with such devices represents multiple elements, it is also an information system.
What is the purpose of the different classes of IP addresses?
The 5 classes of IP addresses were created as the original Internet routing scheme in the 1970's.
These 5 classes were proposed by the IEEE committee.
These classes were not created, after the fact, to meet the needs of an ever expanding Internet.
When the IEEE proposed these classes; each of the 5 classes were 'designed' for a specific purpose.
Class A was designed to meet the needs of large networks.
This class will only support 126 networks; but each network can support 16,777,214 hosts.
Class B was designed for medium-sized networks.
This class will support 16,384 networks; and limited to 65,534 hosts per network.
Class C was designed for small networks; thus the number of hosts per network will be small, however it will support many more networks total.
Class C supports 2,097,152 networks; but only 254 hosts per network.
All Class A addresses are already used up and Class B addresses are rather difficult to obtain.
Most new connections are assigned Class C addresses.
However; if Class C does not meet the requirements of an organization, multiple and multiple Class C addresses can be assigned to fill the need for Internet connectivity (because has mentioned Class C only supports 254 hosts per network, so if their network is large they will have to use many of them).
To understand these classes, just know that they were designed with simple arithmetic.
The number of networks allowed per Class is just the number of possible Network ID's for a given Class range.
The number of hosts allowed per Class is just the number of possible Host ID's for a given Class range.
For example Class A has range of 1.0.0.0-126.0.0.0 & uses only the first octet (1.-126.)
to define the Network ID portion of each IP address in the range of Class A. As you remember Class A supports only 126 different networks. Thus, you can see the simple arithmetic involved; the number of supported networks is a function of the number of possible Network ID's in the range of A.
However; as stated earlier Class A was designed for LARGE networks. To accomplish this Class A only uses the first octet to define the Network ID portion of each IP address; so that means it has a full 3 octets to define the Host ID portion.
Which means the total number of possible Host ID's in the range of A is a whopping 16,777,214. To calculate the total number of possible Host ID's in Class A, we must add the total possible permutations of each octet. The allowable range for an octet is 0-255 (I'll assume you know binary & why each octet has a range of 0-255). Since zero is a possibility, the possible permutations of each octet is 256. And we know that Class A uses 3 octets for the number of Host ID's. Thus to calculate the total possible permutations we simply multiply 256 by itself 3 times. Like so, 256x256x256=16,777,216 possible Host ID's for Class A.
But, it is not quite that simple as you can see our calculation is off by 2. The reason for this is that 2 possibilities cannot be assigned to a host.
These are: .0.0.0 & .255.255.255.
The reason for this is that .0.0.0 is not a defined host range for the Host ID portion of an IP address, because this address along with its subnet mask is used to identify the network; for example the 10.0.0.0/8 network. The Network ID + .255.255.255 for the Host ID is a special address used as a Directed Broadcast; for example 10.255.255.255. This special address can be used as a destination, but cannot be assigned to any host.
So this is how the IEEE 'designed' the IP address Classes; I hope now it is a little easier to see how the IEEE created these Classes and why. Basically, all these classes do is designate different sized networks on the Internet. They were created as the original Internet routing scheme and are used by routers.
And as for Class D and E; these address classes are reserved.
Class D addresses are reserved for multicasting &
Class E addresses are reserved for experimental purposes.
For all practical purposes, Classes D & E are invalid for assigning host IP addresses on a typical TCP/IP network.
Remember these Classes were proposed in the 1970's, with modern technology, they have very little meaning in the overall scheme anymore-- As IP version 6 is now being implemented and there are much less limitations with IPv6. IP version 6 allows for many many more addresses to be used than IPv4 as IP version 4 addresses are running out and IPv6 will be the addressing of the future.
IPv4 only allows for 4,294,967,295 (about 4 billion addresses), this is calculated by the fact that an IP address is a 32 bit address ( four octets or 4x8=32). To calculate the possible no. of addresses we take 2^32 ( 2 to the 32nd power) = 4,294,967,296.
IPv6 allows for 340,282,366,920,938,463,463,374,607,431,768,211,456 addresses;
IPv6 uses a 128 bit hexadecimal address. So, we calculate this number by taking
2 to the 128th power (2^128).
So IPv4 Classes hold very little meaning anymore from their original designated purpose.
Especially when you take into account the new technology and the methods being used to implement networks today.
For example many networks use private addressing for their internal networks; which by the way private IP addresses have no meaning outside of their intranet and cannot be used to access the internet. So, many networks use private addressing to shield their internal networks from the internet, this does not mean that clients on the network cannot access the internet however. An IP Gateway is used for external access to outside networks (such as the Internet). How an IP Gateway works is that it uses Network Address Translation (NAT); it translates private IP addresses to a valid IP address that can be used to access the Internet (typically using a range of Class C addresses). This has the effect of hiding the internal network from the Internet.
As an example let's say that a network of 2,000 computers is using private IP addressing; but only has a couple hundred computers which need access to the internet at any one time. So that, you can see valid addresses are only used when a client is actually accessing the internet; this saves a lot of addresses from being horded so no one else can use them.
There are many different ways to set up a network and many different internetworking devices that have the effect of 'saving' IP addresses, so that they won't run out or so that networks can be implemented beyond the limitations of the original IP address Classes. Internetworking devices such as an IP Gateway are implemented more for security than a fear of running out of addresses.
So, I took the time you write this answer, because at one point I inevitably asked this same question and many more are bound to ask it. The answer is that IPv4 Classes really don't have much of a purpose anymore; because the Internet has outgrown their intended purpose.
Which prompts the need for a new addressing scheme-- IPv6.
With IPv6 we're not going to run out of addresses any time soon.
