KEP-Software : Information about document 'RFC-793'

Explanation of colors

Queried object
Refers to a base object, e.g. a base protocol or interface.
Refers to a child of the object.
Refers to a dependency. If it changes then this might be impacted as well.
This is an extra visible attribute of the object.
The given object refers to this object. Referrals are only of the main object.

	document											RFC-793
		description															Section 3.1
		rfc										rfc793#section-3.1
		section										Header Format
			document									RFC-793					Section 3.1
			ascii									Header Layout					0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \| Source Port \| Destination Port \| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \| Sequence Number \| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \| Acknowledgment Number \| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \| Data \| \|U\|A\|P\|R\|S\|F\| \| \| Offset\| Reserved \|R\|C\|S\|S\|Y\|I\| Window \| \| \| \|G\|K\|H\|T\|N\|N\| \| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \| Checksum \| Urgent Pointer \| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \| Options \| Padding \| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \| data \| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
			bits16									Source Port					The source port number.
			bits16									Destination Port					The destination port number.
			bits32									Sequence Number					The sequence number of the first data octet in this segment (except when SYN is present). If SYN is present the sequence number is the initial sequence number (ISN) and the first data octet is ISN+1.
			bits32									Ack Number					If the ACK control bit is set this field contains the value of the next sequence number the sender of the segment is expecting to receive. Once a connection is established this is always sent.
			bits4									Data Offset					The number of 32 bit words in the TCP Header. This indicates where the data begins. The TCP header (even one including options) is an integral number of 32 bits long.
			bits6									Reserved					Reserved for future use. Must be zero.
			section									Control Bits					6 bits (from left to right)
			bits16									Window					The number of data octets beginning with the one indicated in the acknowledgment field which the sender of this segment is willing to accept.
			bits16									Checksum					The checksum field is the 16 bit one's complement of the one's complement sum of all 16 bit words in the header and text.
			bits16									Urgent Pointer					This field communicates the current value of the urgent pointer as a positive offset from the sequence number in this segment. The urgent pointer points to the sequence number of the octet following the urgent data. This field is only be interpreted in segments with the URG control bit set.
			bits24									Options					Variable length. Options may occupy space at the end of the TCP header and are a multiple of 8 bits in length. All options are included in the checksum. See spec.
			bits8									Padding					Variable Length. The TCP header padding is used to ensure that the TCP header ends and data begins on a 32 bit boundary. The padding is composed of zeros.