CCNA - Day 10 - IPv4 Header

A router will drop a packet with a TTL of [...]

0

A value of [...] in the IP header 'Version' field indicates IP version 4.

4 (binary 0100)

A value of [...] in the IP header 'Version' field indicates IP version 6.

6 (binary 0110)

IPv4 header 'Flags' field:

Bit [...] = DF bit

1

IPv4 header 'Flags' field:

Bit [...] = MF bit

2

IPv4 header 'Flags' field:

Bit [...] = Reserved, always set to 0

0

IPv4 header 'Flags' field:

What does 'DF bit' stand for?

Don't Fragment bit

IPv4 header 'Flags' field:

What does 'MF bit' stand for?

More Fragments bit

IPv4 header 'Protocol' field: 

Value of 1 = [...]

ICMP

IPv4 header 'Protocol' field: 

Value of 17 = [...]

UDP

IPv4 header 'Protocol' field: 

Value of 6 = [...]

TCP

IPv4 header 'Protocol' field: 

Value of 89 = [...]

OSPF

IPv4 header 'Protocol' field: 

Value of [...] = ICMP

1

IPv4 header 'Protocol' field: 

Value of [...] = OSPF

89

IPv4 header 'Protocol' field: 

Value of [...] = TCP

6

IPv4 header 'Protocol' field: 

Value of [...] = UDP

17

IPv4 header: All fragments of the same packet will have the same value in the [...] field.

Identification

IPv4 header: the 'Checksum' field is [...] bits in length.

16

IPv4 header: the 'Destination IP Address' field is [...] bits in length.

32

IPv4 header: The 'DSCP' field is [...] bits in length.

6

IPv4 header: The 'ECN' field is [...] bits in length.

2

IPv4 header: The 'Flags' field is [...] bits in length.

3

IPv4 header: The 'Fragment Offset' field is [...] bits in length.

13

IPv4 header: The 'Identification' field is [...] bits in length.

16

IPv4 header: The 'IHL' field is [...] bits in length.

4

IPv4 header: The 'Protocol' field is [...] bits in length.

8

IPv4 header: the 'Source IP Address' field is [...] bits in length.

32

IPv4 header: The 'Total Length' field is [...] bits in length.

16

IPv4 header: the 'TTL' field is [...] bits in length.

8

IPv4 Header: The IHL field specifies the length of the header in [...] increments.

4-byte (32 bit)

IPv4 header: What does 'DSCP' stand for?

Differentiated Services Code Point

IPv4 header: What does 'ECN' stand for?

Explicit Congestion Notification

IPv4 header: What does 'IHL' stand for?

Internet Header Length

IPv4 header: What does 'TTL' stand for?

Time to Live

IPv4 header: What is the maximum length of the 'Options' field?

320 bits  /  40 bytes

IPv4 header: What is the maximum value of the 'Total Length' field?

65,535

IPv4 header: What is the maximum value of the IHL field?

15

IPv4 header: What is the minimum length of the 'Options' field?

0 bits

IPv4 header: What is the minimum value of the 'Total Length' field?

20 (=IPv4 header with no encapsulated data)

IPv4 header: What is the minimum value of the IHL field?

5

IPv4 header: Which field indicates the protocol of the encapsulated L4PDU?

Protocol

IPv4 header: Which field indicates the total length of the packet?

Total Length

IPv4 header: Which field is used to check for errors in the header?

Header Checksum

IPv4 header: Which field is used to identify which packet a fragment belongs to?

Identification

IPv4 header: Which field is used to indicate the position of a fragment within an original, unfragmented IP packet?

Fragment Offset

IPv4 header: Which field is used to prevent infinite routing loops?

TTL

IPv4 header: Which field is used to prioritize delay-sensitive network traffic?

DSCP

IPv4 header: Which field provides end-to-end notification of network congestion?

ECN

IPv4 packets are fragmented if they are larger than the [...]

MTU (Maximum Transmission Unit)

The IPv4 header 'Version' field is [...] bits in length.

4

The MTU is usually [...] bytes.

1500

The recommended default TTL of an IPv4 packet is [...]

64

Unfragmented IPv4 packets will always have the MF bit set to [...]

0

What does 'MTU' stand for?

Maximum Transmission Unit

What is the maximum length of the IPv4 header?

60 bytes

What is the minimum length of the IPv4 header?

20 bytes