IP packets are composed of a attack and payload. The IPv4 packet attack consists of:
4 $.25 that accommodate the version, that specifies if it's an IPv4 or IPv6 packet,
4 $.25 that accommodate the Internet Attack Length, which is the breadth of the attack in multiples of 4 bytes (e.g., 5 agency 20 bytes).
8 $.25 that accommodate the Type of Service, aswell referred to as Quality of Service (QoS), which describes what antecedence the packet should have,
16 $.25 that accommodate the breadth of the packet in bytes,
16 $.25 that accommodate an identification tag to advice reconstruct the packet from several fragments,
3 $.25 that accommodate a zero, a banderole that says whether the packet is accustomed to be burst or not (DF: Don't fragment), and a banderole to accompaniment whether added $.25 of a packet chase (MF: Added Fragments)
13 $.25 that accommodate the fragment offset, a acreage to analyze position of fragment aural aboriginal packet
8 $.25 that accommodate the Time to reside (TTL), which is the amount of hops (router, computer or accessory forth a network) the packet is accustomed to canyon afore it dies (for example, a packet with a TTL of 16 will be accustomed to go beyond 16 routers to get to its destination afore it is discarded),
8 $.25 that accommodate the agreement (TCP, UDP, ICMP, etc.)
16 $.25 that accommodate the Attack Checksum, a amount acclimated in absurdity detection,
32 $.25 that accommodate the antecedent IP address,
32 $.25 that accommodate the destination address.
After those 160 bits, alternative flags can be added of assorted length, which can change based on the agreement used, again the abstracts that packet carries is added. An IP packet has no trailer. However, an IP packet is generally agitated as the burden central an Ethernet frame, which has its own attack and trailer.
4 $.25 that accommodate the version, that specifies if it's an IPv4 or IPv6 packet,
4 $.25 that accommodate the Internet Attack Length, which is the breadth of the attack in multiples of 4 bytes (e.g., 5 agency 20 bytes).
8 $.25 that accommodate the Type of Service, aswell referred to as Quality of Service (QoS), which describes what antecedence the packet should have,
16 $.25 that accommodate the breadth of the packet in bytes,
16 $.25 that accommodate an identification tag to advice reconstruct the packet from several fragments,
3 $.25 that accommodate a zero, a banderole that says whether the packet is accustomed to be burst or not (DF: Don't fragment), and a banderole to accompaniment whether added $.25 of a packet chase (MF: Added Fragments)
13 $.25 that accommodate the fragment offset, a acreage to analyze position of fragment aural aboriginal packet
8 $.25 that accommodate the Time to reside (TTL), which is the amount of hops (router, computer or accessory forth a network) the packet is accustomed to canyon afore it dies (for example, a packet with a TTL of 16 will be accustomed to go beyond 16 routers to get to its destination afore it is discarded),
8 $.25 that accommodate the agreement (TCP, UDP, ICMP, etc.)
16 $.25 that accommodate the Attack Checksum, a amount acclimated in absurdity detection,
32 $.25 that accommodate the antecedent IP address,
32 $.25 that accommodate the destination address.
After those 160 bits, alternative flags can be added of assorted length, which can change based on the agreement used, again the abstracts that packet carries is added. An IP packet has no trailer. However, an IP packet is generally agitated as the burden central an Ethernet frame, which has its own attack and trailer.
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