Qos- Introduction - Video By Sikandar Shaik || Dual CCIE (RS/SP) # 35012

[Music] what your service now in this video will see the basic introduction to the quality of service and then we'll see why there is a need for the quality of service what are the different network issues comes and how to overcome that by using some quality of service now before we go ahead let us try to understand what is quality of service so quality of service is a method of giving a priority to some specific information as it goes over the network like take an example in my network normally we have different types of traffic you might be sending some VoIP traffic voice traffic video you have some IP phones connected and you are sending that and also there are some applications used in my network which are using some video conferencing applications and also I have some data traffic as well moving in the network maybe your HTTP traffic or FTP traffic or some database something like that now when they're going to go through the network probably there is a possibility that when you are sending on the router probably it is going on the link now if there is not enough bandwidth or maybe there is a possibility that your FTP traffic that there are some users who are downloading something and the users now the HTTP traffic is almost eating up all your bandwidth and maybe maybe your voice traffic is not clear your voice is not clear the reason is maybe some of the packets are getting dropped and when you are doing some video conferencing applications the video is not coming properly now these are some of the reasons some of the issues you you you can do if you have some less amount of bandwidth available on the link now what we can do here is we can we can simply configure some like we can give a priority for specific traffic saying that if a traffic is coming with a voice or video that should be sent first and it has to stop all the remaining traffic or maybe we can define that the watch traffic should get a guaranteed bandwidth of of 64 kbps on that particular link in case if there is a condition due to low speed links and that can be done by using something called quality of service so quality of service is a method of giving a priority for some specific traffic as it is moving over the network and we can define them in different categories and we can define we can result some amount of bandwidth for specific traffic we can define the priority we can we can tell we can ensure that any any applications like FTP download should not utilize all the bandwidth we can restrict them by using some policy options and that's what you are going to see in this sections now now before we go ahead with the more in detail of different quality of service mechanisms which is which will help us in in improvising your network performance or giving the priority before we would we go ahead we need to understand what are the general issues we have in the network so network quality issues like sometimes you know the small voice packets has to compete with your FTP download and we need to ensure that some packed some traffic should get a high priority which are typically your sensitive traffic like voice and video and we we never want any downtime for this specific application we want to ensure that some some database applications we need to ensure that this it should not be any downtime in accessing those those servers now that can be done by by ensuring that we we can use some quality for different applications that's what we do in the quality of service now there are now why there is in need you know what what are the general problems you have in the network like the first common problem is the lack of bandwidth so you might be trying to send some information over the network but the one link connecting between the routers is just two MVPs and in these two MVPs we need to ensure that we send all the topic now there is no enough bandwidth then probably it will also lead to the packet getting dropped or network getting consistence so first let's try to understand way in which scenarios you will have some bandwidth issues like take an example there is a user as sender is sending its engine in the land at a speed of 10 M appeals and as a receiver or trying to access access the server which can support 100 Mbps so probably when the sender suppose hundred any peers it will try to send at a speed of 1 Mbps but on the vine link we just have 256 kbps so probably the router cannot process the packets at a speed of 10 it's going to send at a speed of 250 kbps and then maybe here 512 but at the end you will not be able to send and with you at the same speed so the overall bandwidth from some sender to receiver probably it will be the least bad with whatever we have so the maximum value band is equals to the bandwidth on the slowest link so that the maximum bandwidth you can send between the two devices or in those scenarios probably we don't have enough bandwidth so the model bottom leg will be like we have the link which is just supporting 256 kbps and you cannot send you cannot send the information more than that because this this link connecting between the two Rascals down to 1 and auto two you can just send it a speed of two three skip details now the next possible thing now packet loss the second problem is the packet loss a packet loss generally happens when the routers refuse the packet and it will try to send the packet if there is the based on the output queue the number of packets it can hold it will all those cycles before it send back again and if it reaches the maximum remain automatically it will start dropping your packets so that is also one common reason let's say if you have a wide traffic coming up and probably that watch traffic is queued and maybe due to due to the output queue is full then it is going to automatically drop your packets and when you're sending some important critical traffic we don't want that to happen so that is that is one more problem here now if there is a packet loss probably you will even have some issues if you are on the phone call you will see the voice will break up because of the sub packets are getting dropped because of the condition you can using some telephone conferencing applications the white end video will not be synchronized your picture is not clear again and if you are downloading some files from some publishing companies the files will be corrupted so many download the file will not be complete so it says when you try to open that particular file it says as corrupted or maybe if your if you work if you are attending a call center probably they say that please hold on while my screen refreshes because when they try to refresh it will take some time because of the network condition and these are the general problems you have in gentlemen in non commonly when we have some network conditions ok so the first one was lack of bandwidth packet loss even there is a possibility that your packets may get delayed now the delay generally depends there are different types of the list we have processing delay with the time taken by the device to process the package queuing delay queuing delay is nothing but how long because the packet will be queued before it sends outside probably that will also take some time depending upon the output queue again and then propagation delay is the time taken before it actually sent outside and these are all the things you know these are all different types of delays matters so when you are sending the information it will also take some time depending upon the depend on different types of delays Ezzor and then the fourth problem will be jitters now eater is a one kind of problem where the packets from the source will reach the destination in different image like normally if you are sending the packets instead extreme that delays the from the source the source end destination between each every packet you have some serial delay normally the common delay but if you have some jitters there will be extraordinay here so ZJ is generally calls based on the condition on the network and the condition can occur either the router interfaces or the provider or the carrier network if the circuit is not working properly now jitter again leads to some some extra maybe some unless a traffic including that so the packets not coming at a common streaming we call it as jitter now these are the four different problems we have with the network condition and to overcome all these things we need to use something called quality of service now quality of service will ensure that whatever the bandwidth available based on the particular bandwidth will will give some priority for specific amount of traffic like we will say that if the watch traffic is coming and also your FTP traffic is coming will say what traffic should be sent first before it sends the watch FTP traffic and we are also saying that FTP traffic should not utilize more than 64 kbps if it is exceeding it will automatically drop it or or reduce the priority something like that so we all we do this we are efficient utilizing the available bandwidth by prioritizing some specific topic and that is what we call as quality of service so probably the next section will see some different tools tools which we use to make this possible just to kick over you on that and in the in the later on coming coming topics will also get into each and every mechanism which is used to overcome these problems you

Channel: Sikandar Shaik

Views: 85,455

Rating: 4.7993526 out of 5

Keywords: ccna vdieos, ccna, qos, ccna qos vdieos, noa

Id: -A2O1edb7sY

Length: 10min 40sec (640 seconds)

Published: Tue Jan 24 2017