Chapter 7 Network Setting
BM2022 Users Guide
92
If the
Primary
and
Secondary DNS Server
fields are not
specified, for instance, left as 0.0.0.0,
the BM2022 tells the DHCP clients that it itself is the DNS server. When a computer sends a DNS
query to the BM2022, the BM2022 forwards the query to the real DNS server learned through IPCP
and relays the response back to the computer.
Please note that DNS proxy works only when the ISP uses the IPCP DNS server extensions. It does
not mean you can leave the DNS servers out of the DHCP setup under all circumstances. If your ISP
gives you explicit DNS servers, make sure that you enter their IP addresses. This way, the BM2022
can pass the DNS servers to the computers and the computers can query the DNS server directly
without the BM2022s intervention.
RIP Setup
RIP (Routing Information Protocol) allows a router to exchange routing information with other
routers. The
RIP Direction
field controls the sending and receiving of RIP packets. When set to:
RX/TX -
the BM2022 will broadcast its routing table periodically and incorporate the RIP
information that it receives.
RX Only -
the BM2022 will not send any RIP packets but will accept all RIP packets received.
TX Only -
the BM2022 will send out RIP packets but will not accept any RIP packets received.
None -
the BM2022 will not send any RIP packets and will ignore any RIP packets received.
The
Version
field controls the format and the broadcasting method of the RIP packets that the
BM2022 sends (it recognizes both formats when receiving).
RIP-1
is universally supported; but RIP-
2 carries more information. RIP-1 is probably adequate for most networks, unless you have an
unusual network topology.
Both
RIP-2B
and
RIP-2M
sends the routing data in RIP-2 format; the difference being that
RIP-2B
uses subnet broadcasting while
RIP-2M
uses multicasting.
Port Forwarding
A NAT server set is a list of inside (behind NAT on the LAN) servers, for example, web or FTP, that
you can make accessible to the outside world even though NAT makes your whole inside network
appear as a single machine to the outside world.
With port forwarding, you can forward incoming service requests to the server(s) on your local
network. You may enter a single port number or a range of port numbers to be forwarded, and the
local IP address of the desired server. The port number identifies a service; for example, web
service is on port 80 and FTP on port 21. In some cases, such as for unknown services or where one
server can support more than one service (for example both FTP and web service), it might be
better to specify a range of port numbers.
In addition to the servers for specified services, NAT supports a default server. A service request
that does not have a server explicitly designated for it is forwarded to the default server. If the
default is not defined, the service request is simply discarded.
For example, let's say you want to assign ports 21-25 to one FTP, Telnet and SMTP server (A in the
example), port 80 to another (B in the example) and assign a default server IP address of
Summary of Contents for BM2022
Page 12: ...15 PART I User s Guide ...
Page 22: ...Chapter 2 Introducing the Web Configurator BM2022 User s Guide 26 ...
Page 55: ...59 PART II Technical Reference ...
Page 56: ...60 ...
Page 60: ...Chapter 5 System Status BM2022 User s Guide 64 ...
Page 86: ...Chapter 6 WiMAX BM2022 User s Guide 90 ...
Page 187: ...Chapter 12 Maintenance BM2022 User s Guide 192 ...
Page 193: ...Chapter 13 Troubleshooting BM2022 User s Guide 198 ...
Page 203: ...Appendix A WiMAX Security BM2022 User s Guide 208 ...
Page 237: ...Appendix C Pop up Windows JavaScript and Java Permissions BM2022 User s Guide 242 ...
Page 273: ...Appendix E Importing Certificates BM2022 User s Guide 278 ...