Nokia M11 T66220, Руководство пользователя

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How your Nokia M11 works
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Copyright Nokia Networks Oy C33833001SE_00
6-9
6.9.1 DHCP for LAN clients
M11 can provide addresses for as many as 253 devices on the network
connected to its Ethernet port. When M11 receives a DHCP request
from a client computer, it determines what address to assign by
checking its DHCP lease table to identify an unused address in its
DHCP range. When it finds an address that should be free, M11 sends a
broadcast message on the network to verify that no other host is using
the same IP address. If another host indicates that it is using the
selected address, M11 selects another address and repeats the
sequence until it finds an address that is not in use.
Dynamic allocation of IP addresses means that an IP address can be
reused when it is no longer needed by the client to which it is assigned.
Dynamic IP address allocation is particularly useful in situations
where clients connect to a network temporarily or where a site needs to
share a limited pool of IP addresses among a group of clients that do
not need permanent IP addresses.
Nokia M11 can also act as a DHCP relay agent. It can relay DHCP
requests to an external DHCP server.
6.9.2 DHCP for WAN port configuration
It is possible to configure Nokia M11 in such a way that it operates as a
DHCP client. It can retrieve IP addresses for the ADSL/ATM channels
from the network. However, the following requirements must be met:
D
ADSL/ATM channels use VC multiplexed or LLC/SNAP RFC
1483 encapsulations for IP or Ethernet packets.
D
IP address information of the WAN interface has been set to
0.0.0.0
Nokia M11 sends a DHCP broadcast message asking for configuration
information from any available DHCP server. If there is an active
DHCP server behind the WAN interface, M11 accepts and uses the
network configuration settings the DHCP server provides to configure
the WAN port parameters.
6.10 Domain Name Service (DNS) relay
Nokia M11 can act as a Domain Name Service relay for the LAN
clients. M11 LAN IP address acts as a DNS server address for all hosts
connected to the LAN. M11 recognises its own name and responds to
name queries with its own name. All other name queries Nokia M11