I have a question about TCP/UDP!

[lekhoi]

Hi,guys
Can you tell me what are the differences between TCP and UDP? which applications UDP was used?
thanks in advance

 

[theonleegr81]

TCP is a connection oriented protocol, which means that everytime a packet is sent say from host A to B, we will get an acknowledgement. Whereas UDP on the other hand, is a connection less protocol.

Where will it be used : TCP -> Say you have a file transfer and you need to ensure that the file reaches intact, and time is not a factor, in such a case we can use TCP.

UDP-> Media Streaming, question is say you are watching a movie…would you prefer that your movie comes..perfectly….but u need to wait a long time before you see the next frame ?..or would you prefer the movie to keep streaming…Yes…The second option is definely better….This is when we need UDP

UDP is used to download videos and big files which can stand some changes in itself.

 

[asafdav2]

why do DNS messages usually use UDP and not TCP?

 

[tomshack]

why do DNS messages usually use UDP and not TCP?

it is easy my friend ,it should be fast otherwise u have to wait long for opening web pages

 

[lambtron]

Can you tell me what are the differences between TCP and UDP? which applications UDP was used?

As theonleegr81 pointed out, udp is often used for streaming. There is another aspect of streaming that was not mentioned, however.

If the stream source is real time, such as a video camera, and tcp is being used, the source node would require a substantial fifo to hold stream data that has been produced by the camera but not yet conveyed to the stream consumer. In the process of streaming to the consumer, packets will inevitably be dropped, thus causing delays that will fill up the producer's buffer. No matter how large that buffer is, it can never be large enough to prevent an eventual overflow. As a result, udp (or rtp) is usually used to convey real time streams.

 

[professional]

and FYI, dns use both tcp and udp. It uses udp for server zone transfers.

 

[Hassan.Mourad]

Guys, Professional,

Yes, DNS uses both TCP and UDP, but for zone transfere DNS uses TCP (needs reliable data exchange between DNS servers), for clients it uses UDP

Regards,
Hassan Mourad

 

[Nimer]

hi

thanks guys ..... whats the TCP frame format and the udp also ....is it affected with ip v6 new standard

regards

 

[the_risk_master]

Hi,

UDP and TCP alike arent affected by IPng or IPv6, IPv6 is just an expansion version of IPs around today

 

[ahmeedzeki]

hi
UDP is a connectionless protocol that does not support the assurance that the message was arrived and each packet are sent seperately that there is a chance that the packets are arrive out of order.
TCP is a protocol that support that the message are arrive correctly and in order because there is a connection during the transmision and this protocol used in loading web pages

 

[echo47]

If you'd like to learn the protocol details, TCP is defined in RFC 793, UDP is defined in 768, and IP is defined in RFC 791.
https://www.rfc-editor.org/rfc-index.html

 

[hossam.algewely]

one of the most famous applications for UDP is VoIP,
VoIP uses a transmission protocol called RTP "Real time transport protocol" which constructs packets based on UDP , in order to be very fast and real time , also retransmission and other acknowledgement techniques are insignificat with voice

 

[bangash]

TCP is connection oriented means very reliable ,secure but alittle time consuming
because three way handshaking is involved in it.means when A want to send data to B
first of all A will tell the other component that i want to send data, then in response B will either accept it or respond negatively if B wants to get data data then he will respond +ively ,and then A will again send an acknowledgement to B that i m sending data ,so there are three signals are involved in that transmission .In this sense it is a little time consuming (a factor of delay arrises).If any of the data packet is lost whlie transmission the next will not be sent untill the recovery for the lost packet isn't made.

where as in the case of UDP not very much efficent,
all of the recovery for the lost packets is made at the last until the whole file is transfered.

 

[asmat_ali]

UDP is used when you want to dowload any file.Because the lost information can be taken at the last, when whole of the file is transfered.
downloading a song or a movie UDP will be the better option