Hitron TECHNOLOGIES CVE1A ユーザーズマニュアル
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HITRON CVE-30360 USER’S GUIDE
CABLE
2.1.4
DHCP LEASE
“DHCP lease” refers to the length of time for which a DHCP server allows a DHCP
client to use an IP address. Usually, a DHCP client will request a DHCP lease
renewal before the lease time is up, and can continue to use the IP address for an
additional period. However, if the client does not request a renewal, the DHCP server
stops allowing the client to use the IP address.
client to use an IP address. Usually, a DHCP client will request a DHCP lease
renewal before the lease time is up, and can continue to use the IP address for an
additional period. However, if the client does not request a renewal, the DHCP server
stops allowing the client to use the IP address.
This is done to prevent IP addresses from being used up by computers that no longer
require them, since the pool of available IP addresses is finite.
require them, since the pool of available IP addresses is finite.
2.1.5
MAC ADDRESSES
Every network device possesses a Media Access Control (MAC) address. This is a
unique alphanumeric code, given to the device at the factory, which in most cases
cannot be changed (although some devices are capable of “MAC spoofing”, where
they impersonate another device’s MAC address).
unique alphanumeric code, given to the device at the factory, which in most cases
cannot be changed (although some devices are capable of “MAC spoofing”, where
they impersonate another device’s MAC address).
MAC addresses are the most reliable way of identifying network devices, since IP
addresses tend to change over time (whether manually altered, or updated via
DHCP).
addresses tend to change over time (whether manually altered, or updated via
DHCP).
Each MAC address displays as six groups of two hexadecimal digits separated by
colons (or, occasionally, dashes) for example 00:AA:FF:1A:B5:74.
colons (or, occasionally, dashes) for example 00:AA:FF:1A:B5:74.
NOTE:
Each group of two hexadecimal digits is known as an “octet”, since it
represents eight bits.
Bear in mind that a MAC address does not precisely represent a computer on your
network (or elsewhere), it represents a network device, which may be part of a
computer (or other device). For example, if a single computer has an Ethernet card
(to connect to your CVE-30360 via one of the LAN ports) and also has a wireless
card (to connect to your CVE-30360 over the wireless interface) the MAC addresses
of the two cards will be different. In the case of the CVE-30360, each internal module
(cable modem module, Ethernet module, wireless module, etc.) possesses its own
MAC address.
network (or elsewhere), it represents a network device, which may be part of a
computer (or other device). For example, if a single computer has an Ethernet card
(to connect to your CVE-30360 via one of the LAN ports) and also has a wireless
card (to connect to your CVE-30360 over the wireless interface) the MAC addresses
of the two cards will be different. In the case of the CVE-30360, each internal module
(cable modem module, Ethernet module, wireless module, etc.) possesses its own
MAC address.
2.1.6
ROUTING MODE
When your CVE-30360 is in routing mode, it acts as a gateway for computers on the
LAN to access the Internet. The service provider assigns an IP address to the CVE-
30360 on the WAN, and all traffic for LAN computers is sent to that IP address. The
CVE-30360 assigns private IP addresses to LAN computers (when DHCP is active),
and transmits the relevant traffic to each private IP address.
LAN to access the Internet. The service provider assigns an IP address to the CVE-
30360 on the WAN, and all traffic for LAN computers is sent to that IP address. The
CVE-30360 assigns private IP addresses to LAN computers (when DHCP is active),
and transmits the relevant traffic to each private IP address.
NOTE:
When DHCP is not active on the CVE-30360 in routing mode, each computer
on the LAN must be assigned an IP address in the CVE-30360’s subnet
manually.
manually.