Asus CX200 - Manual (Page 88)

ASUS CX200 Internet Camera
Appendix B: IP Address, Subnet and Gateway
This section discusses Communities, Gateways, IP Addresses and Subnet
masking
Communities
A community is a string of printable ASCII characters that identifies a
user group with the same access privileges. For example, a common
community name is “public”.
For security purposes, the SNMP agent validates requests before
responding. The agent can be configured so that only trap managers
that are members of a community can send requests and receive
responses from a particular community. This prevents unauthorized
managers from viewing or changing the configuration of a device.
Gateways
Gateway, also referred to as a router, is any computer with two or more
network adapters connecting to different physical networks. Gateways
allow for transmission of IP packets among networks on an Internet.
IP Addresses
Every device on an Internet must be assigned a unique IP (Internet
Protocol) address. An IP address is a 32-bit value comprised of a
network ID and a host ID. The network ID identifies the logical network
to which a particular device belongs. The host ID identifies the particular
device within the logical network. IP addresses distinguish devices on an
Internet from one another so that IP packets are properly transmitted.
IP addresses appear in dotted decimal (rather than in binary) notation.
Dotted decimal notation divides the 32-bit value into four 8-bit groups,
or octets, and separates each octet with a period. For example,
199.217.132.1 is an IP address in dotted decimal notation.
To accommodate networks of different sizes, the IP address has three
divisions – Classes A for large, B for medium and C for small. The
difference among the network classes is the number of octets reserved
for the network ID and the number of octets reserved for the host ID.