WebGate Inc. WB106X-WG1K Benutzerhandbuch
WebEye B106
WebEye B106 User’s Guide
25
considered as network ID.
Note: To explain and understand easily on IP address, the first byte of IP address is marked as X1 in this
manual. And X2 is for the second byte, X3 is for the third byte, and X4 is for the fourth byte.
IP address is constructed as follows.
IP address construction in binary number of each bit
xxxxxxxx (8 bit): X1
xxxxxxxx (8 bit): X2
xxxxxxxx (8 bit): X3
xxxxxxxx (8 bit): X4
2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
E.g. IP address in binary: 11000000. 10101000. 00000001. 00001101 (It is equal to 192.168.1.13)
* Binary number 1 means to take the equivalent decimal number (2
7
, 2
5
, etc) and 0 means to disregard it.
IP address construction in decimal number of each byte
xxx (0 -255: 1 byte): X1
xxx (0 -255: 1 byte): X2
Xxx (0-255: 1 byte): X3 Xxx (0-255: 1 byte): X4
128 64 32 16 8 4 2 1 128 64 32 16 8 4 2 1 128 64 32 16 8 4 2 1 128 64 32 16 8 4 2 1
E.g. IP address in decimal: 192. 168. 1. 13 (It is equal to 11000000. 10101000. 00000001. 00001101)
* Binary number 1 means to take the equivalent decimal number (2
7
, 2
5
, etc) and 0 means to disregard it.
Network masking point is to be expressed with decimal number from 0 to 31. IP address is consisted in 4
bytes. 4 bytes are 32 bits. Network is to be masked on every bit from the first bit to the 32
nd
bit. Masked bit is
marked with binary number ‘ 1’, and the corresponding bits out of provided I P address are defined as network
ID for IP filtering.
Network masking point (0 to 31)
1 2 3 4 5 6 7 8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 0
E.g. Network masking on the 8
th
bit (8): 11111111. 0000000. 00000000. 00000000 (255.0.0.0)
E.g. Network masking on the 16
t h
bit (16): 11111111. 11111111. 00000000. 00000000 (255.255.0.0)
E.g. Network masking on the 24
t h
bit (24): 11111111. 11111111. 11111111. 00000000 (255.255.255.0)
E.g. Network masking on the 32
n d
bit (0): 11111111. 11111111. 11111111. 11111111 (255.255.255.255)
According to masking point, masked network ID is to be different out of the same IP address. For example, if
IP address is described as 192.168.1.13 (11000000.10101000.00000001.00001101) with masking point 24
(255.255.255.0), the IP addresses whose IP address is consisted with
‘11000000.10101000.00000001.xxxxxxxx’ (2
8
(256) pieces of IP addresses) will be allowed or denied from
WebEye.
If you describe an IP address as 192.168.1.13 and put masking point 26 (255.255.255.192), the masked bits
are the first 26 digits and network ID masked as ‘11000000.10101000.00000001.00’. In this case, the IP
addresses whose IP address is consisted with ‘11000000.10101000.00000001.00xxxxxx’ (2
6
(64) pieces of IP
addresses) will be applied with a command of ‘Allow’ or ‘Deny ’.
Applied IP address number according to masking point
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 0
2
31
2
30
2
29
2
28
2
27
2
26
2
25
2
24
2
23
2
22
2
21
2
20
2
19
2
18
2
17
2
16
2
15
2
14
2
13
2
12
2
11
2
10
2
9
2
8
2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
E.g. Masking point 8: 2
24
pieces of IP addresses are applied
E.g. Masking point 16: 2
16
pieces of IP addresses are applied
E.g. Masking point 24: 2
8
pieces of IP addresses are applied
E.g. Masking point 0: 2
0
pieces of IP address (itself) is applied