Alcatel AST570 User Manual page 191

CIDR prefix notation
for IP addresses
Example
AST570 and CIDR
VLSM
3EC 17766 AAAA TCZZA Ed. 04
The more up to date CIDR representation of masks does not refer
to a subnet mask, but to a prefix length.
The prefix number equals the number of ones in the subnet mask.
For example, the subnet mask 255.255.255.0 could also be
written as the prefix /24.
For example:
IP address 10.0.0.138
"
netmask 255.255.255.0
"
With the prefix method this will be written as :
prefix IP address 10.0.0.138/24
"
In the AST570 routing table the prefix notation will be used. This
notation in combination with the support for Supernetting and
Route Aggregation provides the AST570 with a mechanism to
make its and other routers' IP routing tables smaller.
Next to traditional classful netmasking, the AST570 fully supports
the use of variable length subnet masks in its IP routing tables.
14 Networking Services - IP
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