packety ma mega
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gego
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packety ma mega
kto mi napise kolko je 6852125 packetov mega .... dalej ako by sa dalo na routri zmenit to aby mi ukazovalo mega pripadne program z ktoreho vycitam co islo zo siete a co z netu ...
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gego
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fajn si si isty ze to tolko je ??? nema ten packet inu velkost ,?? je to tak ako vravis ??? lebsie povedane nemeni sa to ??, lebo si tak chcem ratat stiahnute data z routra ....test napísal:sorry je to trosku viac (nepocital som hlavicku) IP packet ma 20bytov hlavicku plus max 1500bytov datova cast.
6852125 * 1520b = 9,69GB
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gego
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hm teraz som skusal prikaz ping ... a tam sa ping robi z 32 bajtovimy udajmy packety mi to ties ratalo a bolo len 32 bajtove takze to asi nebude 1520 bajtovgego napísal:fajn si si isty ze to tolko je ??? nema ten packet inu velkost ,?? je to tak ako vravis ??? lebsie povedane nemeni sa to ??, lebo si tak chcem ratat stiahnute data z routra ....
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gego
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chcem ale aby sa dalo rozdelit co som stiahol z netu a co od kamosa /zo siete /jjhacker napísal:upresnim, packet 802.3 (ethernet) moze mat max. velkost 1518 oktetov (bajtov) a min. 64,... nepocitaj ICMP ako frame ethernetu (lebo ma len 32 B), ak chces presne meranie prenosu, stiahni si napr netlimiter alebo banwidthmonitor...
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oborpeto
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pokial viem tak maximalna velkost standartneho ethernet ramca je maximalne 1500 B vsetko ostatne je v nom zapuzdrene...
tych 32 bytov bude pravdepodobne datova cast ...
inak je to minimalna velkost hlavicka Ethernet II (prip. IEEE802.3 LLC+SNAP) + IP hlavicka (ta ma aj nepovinne casti takze to je tazsie) + hlavicka ICMP protokolu...
ked pogooglis najdes presne cisla:)
tych 32 bytov bude pravdepodobne datova cast ...
inak je to minimalna velkost hlavicka Ethernet II (prip. IEEE802.3 LLC+SNAP) + IP hlavicka (ta ma aj nepovinne casti takze to je tazsie) + hlavicka ICMP protokolu...
ked pogooglis najdes presne cisla:)
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jjhacker
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Some of the fields permitted or required in an 802.3 Ethernet frame are as follows:
Preamble
SOF Delimiter
Destination Address
Source Address
Length/Type
Header and Data
FCS
Extension
The preamble is an alternating pattern of ones and zeros used to time synchronization in 10 Mbps and slower implementations of Ethernet. Faster versions of Ethernet are synchronous so this timing information is unnecessary but retained for compatibility.
A SOF delimiter consists of a one-octet field that marks the end of the timing information and contains the bit sequence 10101011.
The destination address can be unicast, multicast, or broadcast.
The Source Address field contains the MAC source address. The source address is generally the unicast address of the Ethernet node that transmitted the frame. However, many virtual protocols use and sometimes share a specific source MAC address to identify the virtual entity.
The Length/Type field supports two different uses. If the value is less than 1536 decimal, 0x600 hexadecimal, then the value indicates length. The length interpretation is used when the LLC layer provides the protocol identification. The type value indicates which upper-layer protocol will receive the data after the Ethernet process is complete. The length indicates the number of bytes of data that follows this field.
The Data field and padding if necessary, may be of any length that does not cause the frame to exceed the maximum frame size. The maximum transmission unit (MTU) for Ethernet is 1500 octets, so the data should not exceed that size. The content of this field is unspecified. An unspecified amount of data is inserted immediately after the user data when there is not enough user data for the frame to meet the minimum frame length. This extra data is called a pad. Ethernet requires each frame to be between 64 and 1518 octets.
A FCS contains a 4-byte CRC value that is created by the device that sends data and is recalculated by the destination device to check for damaged frames. The corruption of a single bit anywhere from the start of the Destination Address through the end of the FCS field will cause the checksum to be different. Therefore, the coverage of the FCS includes itself. It is not possible to distinguish between corruption of the FCS and corruption of any other field used in the calculation.
zdroj: cisco.netacad.net