Header Tables

MAC (Media Access Control) Header
Byte	00	01	02	03	04	05	06	07	08	09	10	11	12	13
0	Destination MAC address						Source MAC address						EtherType

IPv4 Packet Structure (Header + Payload) (RFC791)
Offset	Byte	0								1								2								3
Byte	Bit	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
0	0	Version				IHL				DSCP						ECN		Total Length
4	32	Identification																Flags			Fragment Offset
8	64	Time To Live								Protocol								Header Checksum
12	96	Source IP Address
16	128	Destination IP Address
20	160	Options 0-40 bytes (if IHL > 5)
⋮	⋮
56	448
		Data Payload (in total $2^{16} = 65536$ bytes = 64 kB incl. header and options)

ICMP Header (RFC792)
Offset	Byte	0								1								2								3
Byte	Bit	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
0	0	Type								Code								Checksum
4	32	content depends on the ICMP type and code

TCP segment header (RFC 9293)
Offset	Byte	0								1								2								3
Byte	Bit	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
0	0	Source port																Destination port
4	32	Sequence number
8	64	Acknowledgment number (if ACK set)
12	96	Data offset				Reserved 0 0 0 0				CWR	ECE	URG	ACK	PSH	RST	SYN	FIN	Window size
16	128	Checksum																Urgent pointer (if URG set)
20	160	Options (if data offset > 5. Padded at the end with "0" bits if necessary.)
⋮	⋮
56	448