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Hi,
I want to calculate required bandwidth and bitrate of Ethernet for the application in Automobile.
I have different devices connected to switches and transmit signals at every 100ms. So what could be the required bandwidth and bitrate for the Applikation.
lets say, the total size is around 3000bytes.
The whole system is full duplex.
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It sounds to me like you need to define your environment and you required bit rate, and then you can compute the needed bandwidth.
Shannon's equation is the starting point. It does not care what modulation you use.
Channel capacity (b/s) = Bandwidth (Hz) * logbase2(1 + S/N)
where that term S/N is the signal to noise ratio in watts/watts (not in dB).
Shannon's equation gives you the optimal channel capacity. For practical results, you probably want to degrade your S/N by 3 dB or so, and that will give you a good idea of bandwidth requirements.
So, you should know the required channel capacity c and you should know the expected SNR, sn, in dB, since that's the normal way it's measured.
What I'm calling snw is the SNR given in watts/watts, as required by Shannon's equation. Start with a predicted value of SNR in dB, reduce it by 3 dB, and then here's the bandwidth b required, where that log is logbase 10:
snw = 10 ^ (sn / 10)
b = c / (1.4427 * Log(1 + snw))
All I did was solve Shannon's equation for bandwidth, converting the SNR given in dB to a ratio of watts. Then you can determine what modulation to use.
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How can we differentiate message-oriented protocols and stream-oriented protocols?
Explanation with examples would be highly appreciated.
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TCP is a stream oriented protocol and UDP is a message-oriented protocol.
TCP receives the stream of bytes from application layer protocols and divide it in to segments and pass it to IP. But UDP receives already divided or grouped bytes of data from application protocols and add UDP headers which will become datagram and send it to IP, then application layers has the burden of dividing the streams of data in to messages when they run on top of UDP .
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I want to upgrade a network infrastructure to include 1000Mb switches and 10/100/1000 auto sensing network interface cards in each desktop. Recommend the cabling type that you would use in this network. Also, I have 100BaseTX cabling, and I need to provide access to a machine that is located 400 meters from the switch. What strategy could be used to accomplish this task?
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Brian, I will make some assumptions here; so please excuse me for that! Let us say that the upgraded switches uses Gigabit fiber SFP's, as the switch can support either copper of fiber. VDSL seems a bit dramatic, you could simply use a fiber to copper media converter. This method means the media converts a copper connection with auto-negotiation to a fiber interface where duplex and speed is fixed by the connection set by the fiber SFP on the switch. On the other hand you could still have a copper switch converted to fiber and then back to copper at the end client device. Media converters are generally a low cost and a reasonable option when a scenario such as this arises.
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Hi Rupam,
Unix severs become instable if you install by compilation some services which need new library, and new release of existing library. At home I have a server with an old release of the french distrib Mandriva 2010 it was boted last year in august..
In order to manage correctly my linux servers When I have a request for a new program a made a test on a virtual machine and if the compilation need to many other installations I sais no !
The main goal for me is to give access to computer power for every body in the unit not for solved one problem for one guy, the global quality is a mandatory.
cheers
Pierre Léonard
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Based on the difference between IPv4 and IPv6, should a company upgrade its networks to IPv6? Moreover, suppose you have 3 routers in a network design. Would you use static or dynamic routing to connect the routers? I would suppose IPv6 would be the way to go, and with only 3 routers, I am guessing Static would be the best option. However, I could be wrong, and this is why I am asking for some opinions on the matter.
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IPv6 is future of all networks and internet. To switch to the new IPv6 first you need clear plan for current and future . Be in mind that all IPv6 compatible with leayer two device. The problem and different in layer three. So ,to configure your devices base in network plan for the current and future. For example in your case it is better to use static configuration to configure your router. However in your last answer to coexistence plan by use dual stack ,for my experience all ipv6 scenario support ipv4. To do this also need clear plan .you can use native ipv6 between the router and uses tunnel ipv4 in ipv6 . Or you can you coexistence plan for the end devices. Besides, all today version of operating system support dual stack ipv6-ipv4.
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As above.
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Are you asking for references for prototype or you need real time scenarios to know where it is used.