TCP/IP Detailed Flashcards
1
Q
IP Header Fields
A
Version Header Length TOS Total Length Identification Flags Fragment Offset TTL Protocol Header Checksum Source Address Destination Address IP Options
2
Q
IP Total Length field byte offset
A
offset 2
3
Q
IP Identification field byte offset
A
offset 4
4
Q
IP Flags field byte offset
A
7th byte high order 3 bits
5
Q
Fragment Offset field byte offset
A
offset 7
6
Q
TTL field byte offset
A
offset 8
7
Q
Protocol field byte offset
A
offset 9
8
Q
Header Checksum field byte offset
A
offset 10
9
Q
Source Address field byte offset
A
offset 12
10
Q
Destination Address field byte offset
A
offset 18
11
Q
IP Options field byte offset
A
offset 20
12
Q
Header Length minimum value
A
5 - multiply by 4 to get byte count
13
Q
IP Header default length
A
20 bytes
14
Q
Source IP field length
A
4 bytes
15
Q
Destination IP field length
A
4 bytes
16
Q
IP Flags
A
x reserved - High order 8th bit
D Do not fragment - High order 7th bit
M More fragments follow - High order 6th bit
17
Q
IP RFC
A
791
18
Q
IP protocol field - 0x01
A
1 - ICMP
19
Q
IP protocol field - 0x11
A
17 - UDP
20
Q
IP protocol field - 0x06
A
6 - TCP
21
Q
IP protocol field - 0x02
A
2 - IGMP
22
Q
TCP Header fields
A
Source Port Destination Port Sequence Number Acknowledgment number Offset Reserved Flags Window Checksum Urgent Pointer TCP Options
23
Q
UDP Header fields
A
Source Port
Destination Port
Length
Checksum
24
Q
TCP RFC
A
793
25
UDP RFC
768
26
ICMP Header Fields
Type
Code
Checksum
Other message specific info
27
Source Port field byte offset
offset 0
28
Destination Port field byte offset
offset 2
29
Sequence Number field byte offset
5th-8th bytes offset 4
30
Acknowledgment Number field byte offset
9th-12th bytes offset 8
31
TCP offset field byte offset
high order nibble; offset 12
32
TCP Flags field byte offset
offset 13
33
Window field byte offset
offset 14
34
TCP Checksum field byte offset
offset 16
35
TCP Urgent pointer field byte offset
offset 18
36
TCP Flags from low byte order
```
FIN
SYN
RST
PSH
ACK
URG
ECN
CWR
```
37
ECN stands for?
Explicit Congestion Notification
38
TCP Options 0
End of Options list
39
TCP Options 1
No Operation, Pad
40
TCP Options 2
Maximum Segment size
41
TCP Options 3
Windows Scale
42
TCP Options 4
Selective ACK ok
43
TCP Options 5
Timestamp
44
TCP Default Header Size
20 bytes
45
UDP Source Port field byte offset
0 bytes
46
UDP Destination Port field byte offset
2 bytes
47
UDP Length field byte offset
4 bytes
48
UDP Checksum field byte offset
6 bytes
49
UDP default header length
8 bytes
50
ICMP type field byte offset
0 bytes
51
Code field byte offset
1 bytes
52
ICMP Checksum field byte offset
2 bytes
53
ICMP Other message specific info
4 bytes
54
ICMP type code 0x00
0 Echo reply
55
ICMP type code 0x03
3 Destination unreachable
56
ICMP type code 0x04
4 Source Quench
57
ICMP type code 0x05
5 Redirect
58
ICMP type code 0x06
6 Echo
59
ICMP type code 0x09
9 Router Advertisement
60
ICMP type code 0x0b
11 Time Exceeded
61
ICMP type code 0x11
17 Address mask request
62
ICMP type code 0x12
18 Address mask reply
63
DNS Header fields
```
Length (TCP Only)
ID
QR
Opcode
AA
TC
RD
RA
Z
RCODE
QDCOUNT
ANCOUNT
NSCOUNT
ARCOUNT
Question Section
Answer Section
Authority Section
Additional Information Section
```
64
QR field Codes
0 - Query
| 1 - Response
65
DNS Opcodes
0 - Standard query (Query)
1 - Inverse Query (IQuery)
2 - Server Status request (STATUS)
66
AA field definition
1 - Authoritative Answer
67
TC field definition
1 - Truncation
68
RD field definition
1 - Recursion Desired
69
RA field definition
1 - Recursion Available
70
Z field definition
Z reserved, set to 0
71
Response Codes
```
0 - No error
1 - Format error
2 - Server Failure
3 - Non-existant domain (NXDOMAIN)
4 - Query type not implemented
5 - Query refused
```
72
QDCOUNT definition
Number of entries in Question section
73
Ping fields
```
Type
Code
Checksum
Identifier
Sequence number
Data
```
74
ARP header
```
Hardware Address Type
Protocol Address type
H/w Addr Len
Prot. Addr. Len
Operation
Source hardware address
Source Protocol address
Traget Hardware Address
Target Protocol Address
```
75
tcpdump -e
Display data link header
76
tcpdump -F
filter expression in file
77
tcpdump -i
Listen on interface
78
tcpdump -n
don't resolve IP address
79
tcpdump -r
read packet from file
80
tcpdump -s
get snaplen bytes from each packet
81
tcpdump -S
use absolute TCP sequence numbers
82
tcpdump -t
don't print timestamp
83
tcpdump -v
verbose mode
84
tcpdump -w
write packet to file
85
tcpdump -x
display in hex
86
tcpdump -X
display in hex and ASCII
87
IPv6 Header Size
40 bytes
88
IPv6 Address Size
128 bits
89
IPv4 TOS field is now what in IPv6
Traffic Class
90
IPv4 TTL field is now what in IPv6
HOP
91
IPv4 Protocol field is now what in IPv6
Next Header
92
IPv6 Header
```
Version 0-4 bytes
Traffic class 5-12 bytes
Flow label 12-31 bytes
Payload Length 32-47
Next Header
Hop Limit
Source Address
Target Addresss
```
