maximum 60 octets minimum 20 octets
in tcp header (32 bits) we have a field that is called options and padding that has variable in length and the header length shows the actual header size i.e size of 20 octets+size of options and padding field and in UDP we dont have any field like that and its header is fixed of 8 OCTETS (32 bits header size) refrence: WIRELESS COMMUNICATIONS AND NETWORKS by William Stallings Second Edition pg 91(see fig)
An Ethernet frame has a 14 byte header, a data section, and a 4 byte trailer 14 byte header consist of destination address, source address and type The trailer is for CRC (Cyclic redundancy Check) An Ethernet frame can contain an IP and TCP PDU. IP header most important parts consists of (Version,IHL, Total length,Protocol, source and destination address) In details (Version,Header length,Differentiated services field, total Length, Identification, Flags, fragment offset, Time to live, protocol, header checksum, source and destination address). TCP header most important parts consists of (Source port, Destination port and header Length) In details (Source Port, Destination Port, Sequence number, Acknowledgment number, Header length,Flags,Window and check sum). The details of the IP and TCP header have been taken from a Network protocol Analyzer Wireshark on my own pc.
window
The internet header padding is used to ensure that the internet ends on a 32 bit boundary. The padding is zero.
The protocol field, in the IP header, identifies what kind of data is in the IP packet - the upper-layer protocol. For example, if the code is 6, that means that the data is a TCP segment.
The size of a TCP segment encapsulated by an IP header does not have a fixed size and can vary based on the data being transmitted. However, the maximum size of a TCP segment is typically constrained by the Maximum Transmission Unit (MTU) of the network, which is commonly around 1500 bytes for Ethernet. Given that the IP header is 20 bytes, the maximum TCP segment size would be approximately 1480 bytes if there are no additional headers or options. In practice, the exact size would depend on the TCP header size and any options included.
2^16 bytes - size of TCP header
TCP (Transmission Control Protocol) uses a variable header size that typically ranges from 20 to 60 bytes. The standard header size is 20 bytes, which includes fields such as source and destination ports, sequence number, acknowledgment number, and control flags. Additional options can extend the header size, but the maximum size for a TCP packet, including the header and data, can be up to 65,535 bytes.
In the commonly used TCP/IP communications, that would either be a TCP header, or a UDP header.In the commonly used TCP/IP communications, that would either be a TCP header, or a UDP header.In the commonly used TCP/IP communications, that would either be a TCP header, or a UDP header.In the commonly used TCP/IP communications, that would either be a TCP header, or a UDP header.
in tcp header (32 bits) we have a field that is called options and padding that has variable in length and the header length shows the actual header size i.e size of 20 octets+size of options and padding field and in UDP we dont have any field like that and its header is fixed of 8 OCTETS (32 bits header size) refrence: WIRELESS COMMUNICATIONS AND NETWORKS by William Stallings Second Edition pg 91(see fig)
It is a TCP Header
Both TCP and UDP have origin and destination ports - and that is about all the similarity there is between the two. TCP has several other fields that UDP doesn't have, including window size; a consecutive byte numbering (to figure out where to place a TCP segment in a data stream); the bytes that the other side is expected to send; and others.
a tcp header contains the information of the source and destination networks and well as what port to access with out it the packet would not know where to go
both tcp and udp
The sequence number, acknowledge number, and Window fields.
To reassemble the segments into data.
The checksum field in a TCP header is used to verify the integrity of the TCP segment during transmission. It checks for errors that may have occurred in the data, ensuring that the segment received is the same as the one sent. The checksum is calculated over the TCP header and the data payload, and the receiver recalculates the checksum to confirm its accuracy. If the checksums do not match, the segment is considered corrupted and is typically discarded.