ICMP Address Mask Reply

Address Mask Reply is an ICMP message, used to reply to an Address Mask Request message with an appropriate subnet mask.

Message Format:

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

Type = 18

Code = 0

Header Checksum

Identifier

Sequence Number

Address Mask

• Type must be set to 18.
• Code must be set to 0.
• The Address Mask should be set to the subnet mask.

See also

• ICMP Address Mask Request

References

• RFC 950