IP Address and Network (Subnet) Mask:
IP stands for Internet Protocol. An IP address consists of a series of four
numbers separated by periods, that identifies a single, unique Internet computer host in an IP network. Example:
192.168.2.1. It consists of 2 portions: the IP network address, and the host identifier.
The IP address is a 32-bit binary pattern, which can be represented as four cascaded decimal numbers separated by “.”:
aaa.aaa.aaa.aaa, where each “aaa” can be anything from 000 to 255, or as four cascaded binary numbers separated by “.”:
bbbbbbbb.bbbbbbbb.bbbbbbbb.bbbbbbbb, where each “b” can either be 0 or 1.
A network mask is also a 32-bit binary pattern, and consists of consecutive leading
1’s followed by consecutive trailing 0’s, such as
11111111.11111111.11111111.00000000. Therefore sometimes a network mask can also be described simply as “x”
number of leading 1’s.
When both are represented side by side in their binary forms, all bits in the IP address that correspond to 1’s in the network
mask become part of the IP network address, and the remaining bits correspond to the host ID.
For example, if the IP address for a device is, in its binary form,
11011001.10110000.10010000.00000111, and if its network mask is,
11111111.11111111.11110000.00000000
It means the device’s network address is
11011001.10110000.10010000.00000000, and its host ID is,
00000000.00000000.00000000.00000111. This is a convenient and efficient method for routers to route IP packets to their
destination.
ISP Gateway Address:
(see ISP for definition). The ISP Gateway Address is an IP address for the Internet router located
at the ISP's office.
ISP:
Internet Service Provider. An ISP is a business that provides connectivity to the Internet for individuals and other
businesses or organizations.
LAN:
Local Area Network. A LAN is a group of computers and devices connected together in a relatively small area (such
as a house or an office). Your home network is considered a LAN.
MAC Address:
MAC stands for Media Access Control. A MAC address is the hardware address of a device connected to a
network. The MAC address is a unique identifier for a device with an Ethernet interface. It is comprised of two parts: 3 bytes
of data that corresponds to the Manufacturer ID (unique for each manufacturer), plus 3 bytes that are often used as the
product’s serial number.
NAT:
Network Address Translation. This process allows all of the computers on your home network to use one IP address.
Using the broadband router’s NAT capability, you can access the Internet from any computer on your home network without
having to purchase more IP addresses from your ISP.
Port:
Network Clients (LAN PC) uses port numbers to distinguish one network application/protocol over another. Below is a
list of common applications and protocol/port numbers:
Application Protocol Port
Number
Telnet TCP
23
FTP TCP
21
SMTP TCP
25
POP3 TCP
110
H.323 TCP
1720
SNMP UCP
161
SNMP Trap
UDP
162
HTTP TCP
80
PPTP TCP
1723
PC Anywhere TCP
5631
PC Anywhere UDP
5632
PPPoE:
Point-to-Point Protocol over Ethernet. Point-to-Point Protocol is a secure data transmission method originally
created for dial-up connections; PPPoE is for Ethernet connections.
PPPoE
relies on two widely accepted standards,
Ethernet and the Point-to-Point Protocol. It is a communications protocol for transmitting information over Ethernet between
different manufacturers
Protocol:
A protocol is a set of rules for interaction agreed upon between multiple parties so that when they interface with
each other based on such a protocol, the interpretation of their behavior is well defined and can be made objectively,
without confusion or misunderstanding.
Router:
A router is an intelligent network device that forwards packets between different networks based on network layer
address information such as IP addresses.
Subnet Mask:
A subnet mask, which may be a part of the TCP/IP information provided by your ISP, is a set of four
numbers (e.g. 255.255.255.0) configured like an IP address. It is used to create IP address numbers used only within a
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