REVIEW OF ADDRESSING
EMM-E6 User’s Guide
1-31
1.10.8
Addressing Example
A network manager, planning for the configuration of a network of 60
hosts, desires to implement subnets to create logical divisions between
different groups of workstations and devices. The Internet Assigned
Numbers Authority has supplied the company with a Class C Network
Address; 222. 131. 99. XXX.
Examining Table 1-6 for subnet masking forms, the Network Manager
decides that, due to the extent of subnetting to be implemented, the last
option in the subnet table is not realistic, as that configuration offers only
two subnets. Likewise, the first three options are unacceptable, as they
would create an excessively large number of subnets with relatively few
individual hosts per subnetwork. This leaves decimal masks of 248 (31
subnets, 6 hosts each), 240 (15 subnets, 14 hosts each), and 224 (6
subnets, 30 hosts each). Any of these decimal masks would support the
number of Host IDs to be configured. Looking ahead, the Network
Manager realizes that adding Host IDs to a full network can involve a
total reconfiguration of subnet strategies, and opts for the decimal mask
240, which provides room for the configuration of 210 Host IDs.
After taking time to fully plan and delineate the required subnets, assign
them to departments within the company, plan out the initial Host IDs for
existing devices within those subnets and configure the router(s) which
will interconnect the various subnets, the Network Manager determines
where on the network the network management station will reside. The IP
Host ID of this network management station will be essential when
configuring the network devices for sending SNMP Traps.
On any subnet, one Host ID must be reserved for a connection to the
router(s) which will interconnect multiple subnets.
NOTE
CH1Book Page 31 Wednesday, March 20, 1996 7:48 AM
