ZyXEL Communications USG110, Руководство пользователя

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Chapter 10 Interfaces
ZyWALL USG Series User’s Guide
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• IP address - If the DHCP client’s MAC address is in the Zyxel Device’s static DHCP table, the interface
assigns the corresponding IP address. If not, the interface assigns IP addresses from a pool, defined by
the starting address of the pool and the pool size.
The Zyxel Device cannot assign the first address (network address) or the last address (broadcast
address) in the subnet defined by the interface’s IP address and subnet mask. For example, in the first
entry, if the subnet mask is 255.255.255.0, the Zyxel Device cannot assign 50.50.50.0 or 50.50.50.255. If
the subnet mask is 255.255.0.0, the Zyxel Device cannot assign 50.50.0.0 or 50.50.255.255. Otherwise, it
can assign every IP address in the range, except the interface’s IP address.
If you do not specify the starting address or the pool size, the interface the maximum range of IP
addresses allowed by the interface’s IP address and subnet mask. For example, if the interface’s IP
address is 9.9.9.1 and subnet mask is 255.255.255.0, the starting IP address in the pool is 9.9.9.2, and the
pool size is 253.
• Subnet mask - The interface provides the same subnet mask you specify for the interface. See IP
Address Assignment on page 401 .
• Gateway - The interface provides the same gateway you specify for the interface. See IP Address
Assignment on page 401 .
• DNS servers - The interface provides IP addresses for up to three DNS servers that provide DNS services
for DHCP clients. You can specify each IP address manually (for example, a company’s own DNS
server), or you can refer to DNS servers that other interfaces received from DHCP servers (for example,
a DNS server at an ISP). These other interfaces have to be DHCP clients.
It is not possible for an interface to be the DHCP server and a DHCP client simultaneously.
WINS
WINS (Windows Internet Naming Service) is a Windows implementation of NetBIOS Name Server (NBNS)
on Windows. It keeps track of NetBIOS computer names. It stores a mapping table of your network’s
computer names and IP addresses. The table is dynamically updated for IP addresses assigned by
DHCP. This helps reduce broadcast traffic since computers can query the server instead of
broadcasting a request for a computer name’s IP address. In this way WINS is similar to DNS, although
WINS does not use a hierarchy (unlike DNS). A network can have more than one WINS server. Samba
can also serve as a WINS server.
PPPoE/PPTP/L2TP Overview
Point-to-Point Protocol over Ethernet (PPPoE, RFC 2516) and Point-to-Point Tunneling Protocol (PPTP, RFC
2637) are usually used to connect two computers over phone lines or broadband connections. PPPoE is
often used with cable modems and DSL connections. It provides the following advantages:
• The access and authentication method works with existing systems, including RADIUS.
• You can access one of several network services. This makes it easier for the service provider to offer
the service
• PPPoE does not usually require any special configuration of the modem.
Table 136 Example: Assigning IP Addresses from a Pool
START IP ADDRESS POOL SIZE RANGE OF ASSIGNED IP ADDRESS
50.50.50.33 5 50.50.50.33 - 50.50.50.37
75.75.75.1 200 75.75.75.1 - 75.75.75.200
99.99.1.1 1023 99.99.1.1 - 99.99.4.255
120.120.120.100 100 120.120.120.100 - 120.120.120.199