CBXi IP Controller |
IP Networking
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Subject to change without notice
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In CIDR notation, /16 means that 16 of these bits represents the subnet, and the remainder specifies the
host:
CIDR
192
.
168
.
2
.
54
/
16
IP
Address
decimal
192
.
168
.
2
.
54
IP
Address
Binary
1 1 0 0 0 0 0 0 . 1 0 1 0 1 0 0 0 . 0 0 0 0 0 0 1 0 . 0 0 1 1 0 1 1 0
16 bits representing the subnet
host
Equivalen
t subnet
mask
255
.
255
.
0
.
0
CIDR
55
.
231
.
77
.
3
/
24
IP
Address
decimal
55
.
231
.
77
.
3
IP
Address
Binary
0 0 1 1 0 1 1 1 . 1 1 1 0 0 1 1 1 . 0 1 0 0 1 1 0 1 . 0 0 0 0 0 0 1 1
24 bits representing the subnet
host
Equivalent
subnet
mask
255
.
255
.
255
.
0
DEFAULT GATEWAY
Devices on the same subnet can address
IP
packets to each other without using a router device.
To communicate with devices on another subnetwork, the traffic must be routed through a router
device’s WAN port. When a device needs to communicate with an IP address that is not on the same
network, i
t sends the packet to the Default Gateway, which is usually the subnet’s Router.
Note
: Some
BACnet
services use “broadcasts” (e.g. “
Who-Is
”). On a
LAN
with standard routers, these
broadcasts are “blocked”. As a result,
BACnet
broadcasts are limited to the
IP Subnet
of the
BACnet
device. With a
BACnet/IP
network of 2 or more
IP
subnets, a device that can act as a BACnet/IP
Broadcast Management Device (BBMD) must be used.
