Testning for pakketab på Windows

Pakketab kan forekomme i transmissioner over et netværk og også over internettet. Afhængigt af om sessionskontroller bruges på forbindelsen, forårsager pakketab , hvilket resulterer i en højere transmissionsafslutningstid, eller det resulterer i . Genoverførsel af mistede pakker forårsager ekstra netværkstrafik. Det er ineffektivt, dyrt og mister tid.

For enhver standardpåføring kan langsomme responstider være irriterende, og tabet af den lejlighedsvise pakke øger trafikmængderne lidt. For interaktive applikationer, såsom VoIP , video streaming , og videokonference , pakketab kan være ødelæggende. Disse applikationer genererer store mængder af trafik, selvom pakker leveres med succes. Genoptagelse gør tingene værre.

I tilfælde af VoIP og videokonference , packet loss does not trigger re-transmission because there isn’t time to hold up the delivery of data to the user interface, waiting for that missing piece. Fortunately, each packet represents such a small slice of a voice or video stream that one packet’s payload would not be noticeable if missed out on the delivered presentation. Imidlertid vil en række mistede pakker eller hyppige, intermitterende pakketab. of sound or video. Lyden eller videoen vil have uregelmæssigheder i den, eller den vil hænge eller hoppe.

Video -streamingtjenester beskæftiger sig med pakketab forskelligt. De har ikke et sådant pres som realtid som interaktive applikationer, der bærer live kommunikation mellem to eller flere mennesker. Video -streaming er afhængig af buffering .

Videoafspilningsapplikationen gemmer op flere minutters optagelser, før den begynder at afspille videoen. The amount of video time that it stores in its buffer is calculated on the detected bit rate of the connection with a percentage added on for expected packet loss. In some cases, video applications can negotiate en lavere kvalitet af videoen to compensate for a slower connection. Men hvis pakketabshastigheden på forbindelsen er , the buffered video will run down. Hvis der ikke er nogen video tilbage i bufferen, skal videoafspilleren pause, indtil der er modtaget tilstrækkelig videotid.

dårlig kvalitet Og det forårsager videostrømning til .

Relateret indlæg:

Transportlag protokoller. Den første af disse er ' system. TCP includes procedures for checking that packets arrive and then request a replacement for a lost packet. The other system is the UDP (User Datagram Protocol) . This does not establish a session and so it is called “ forbindelsesløs .' UDP has no way to enable receivers to request retransmission.

TCP eller UDP explain why packet loss creates extra traffic in some cases but not in others. So, in some cases, it causes a poor quality of service and in others, it creates a slow service. I alle tilfælde, .

kapacitet

It is better to detect a packet loss rate on your network and on transmission from particular sources before you put a new multi-media application live for the users to access. Dermed,

operativ system

Der er en række en advarsel

Windows interface. You need to open a Kommandoprompt

og type cmd . Klik på Kommandoprompt

Standard gateway

internettet . So, we are just looking at the stretch of communications on the private network.

Gå ind ipconfig

Standard gateway . In the example shown above, that address is 192.168.0.1. This is a typical IP address for the default gateway on a private network.

Now you can launch a test for a connection to and from the Default Network. Type Ping . In the example, that address was 192.168.0.1. So, the Ping command should be

.

The example run of 100 tests above shows that there was still no packet loss encountered on the network. This is good because it shows that the network is able to cope with its current throughput demand. Imidlertid,

. If packets arrive at a switch at a faster rate than that device can handle, the switch initially buffers the incoming packets. Once that queue is full, new packets arriving cannot go anywhere else and so packets will be lost until the switch empties out some room in the buffer.

.

Se nøjagtigt hvilken enhed der er i problemer .

trafikformning .

Traffic shaping algorithms involve identifying the packets that relate to different applications and then slowing some application traffic to give priority to other traffic at each switch. Dette er

droslede Af din internetudbyder (ISP). In this scenario, the ISP slows down or drops packets for certain applications and video streaming is a particularly big target for some ISPs.

Throttling is very difficult to detect or prove. Som det Målretning af videotrafik

.

Jitter

minimum , maksimum , og Gennemsnitlig rundvisningstid For alle pakker i testkørslet.

Variationen i pakkeleveringstid kaldes ryste and it is a bad condition for interactive applications. As VoIP and video conferencing don’t use any session control or buffering, they need packets to arrive in order and at a regular speed. They don't have time to re-sequence arriving packets, so if the following packet travels faster and arrives before the packet that was sent in front of it, the VoIP application won't check but will play those data segments in the order they Ankom - hvilket resulterede i finurlige lyde.