D-Link DI-300 series Instruction Manual

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 1
D-Link Router Family Frequently Asked Questions (FAQ)
Part I: General Product Overview Questions
1. What is the Router product family?
The Router family of products are a set of multiprotocol remote
access routers that deliver a feature-rich, reliable, and secure
interconnection between your LAN and the remote network such as
Internet or Corporate network via ISDN. The Router product’s
unique features make the interconnection flexible and easy to
upgrade. Router supports IP routing, IPX routing, and
Transparent Bridging. It supports Ethernet, ISDN, and POTS port.
Router can be managed via either RS-232 or Telnet. Its menu-
driven System Management Terminal provides an easy-to-use
interface.
2. What ISDN switches and B Channel protocols are supported by the
Router?
The Router supports the following ISDN switches:
European switches:
DSS1 (also used in other countries)
1TR6
North American switches:
AT&T: NI1, Point-to-Point, Point to Multipoint
Northern Telecom DMS100: NI1, Custom
The Router supports the PPP protocol in the B channels.
3. What are some of the major applications for the Router?
Some of the major applications of the Router include:
Internet Access
The Router can be set up to access the Internet in 15 minutes.
In addition, the Router provides an economic way for small office
to connect to Internet (see Subject 8 for Internet Single User
Account).
LAN-to-LAN Connection
The Router can dial to or answer calls from another remote access
router connected to a different network. The Router supports
TCP/IP, Novell IPX routing and has the capability to bridge any
Ethernet protocol.
Telecommuting Server
The Router allows remote users to dial-in and gain access to your
LAN. This feature enables users that have workstations with
remote access capabilities, e.g., Windows 95, to access the
network resources without physically being in the office.
4. What are the benefits of the Router over other vendors’
products?

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 2
The Router incorporates features not present on most of their
competitors' products.
Internet Single User Account (SUA) Support
Please see Subject 9 for details.
Multiprotocol Router
The Router is the only remote access router supporting IP
Routing, IPX routing, and Transparent Bridge.
Telecommuting Server
In addition to providing both ISDN and modem access for remote
users, the Router also support dynamic IP address assignment and
Windows 95 compatibility. This makes the Router an ideal product
for serving Windows 95 telecommuter and mobile users. The Router
offers support for these accounts that will allow multiple users
on the LAN (Local Area Network) to access the Internet
concurrently for the cost of a single user.
5. What other Remote Access Servers are compatible with the Router?
The Router has successfully gone through PPP MP compatibility
tests with 30+ vendors in October, 1996 at Pacific Bell.
Furthermore, the Router has been tested extensively with Cisco
routers and Ascend routers (both Max and Pipeline).
Part II: Application Setup Questions
1. What does my computer need to connect to the Router?
You will need an ethernet card that supports a 10baseT (RJ-45
jack) ethernet interface.
If you intend to connect your computer directly to the Router
without a hub in between, you will need to use a ‘crossover’
cable and a 10baseT ethernet card. The ‘crossover’ cable is a 4-
pair RJ-45 cable with pins #1 and #3 swapped, and pins #2 and #6
swapped.
To initially configure your Router, you need to have an RS-232
cable and a communications program on your computer.
In order to access the WAN (Wide Area Network) on the Router's
ISDN connection, you need to have a Ethernet connection in your
computer.
2. How can I remotely configure my Router using a modem?
You can configure your Router remotely through a modem call.
This setup requires an external ‘local’ modem.
Local Remote
v v
[Router]--[Null Modem]-[Modem]--(phone line)--[Modem]-[Computer]
^
RS-232 Cable

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 3
The procedure for this setting up this application is as follows:
- Set the modem on the ‘local’ end to IGNORE DTR
- Set the modem on the ‘local’ end to Auto Answer (ATS0=1)
- Set the Router Port Speed (menu 24.2) to be 19200 if the
‘local’ modem is a 14.4K, and 38400 if it is faster (
28.8K+)
- Dial the ‘local’ modem with the ‘remote’ modem.
3. How can I set up my Router as an Internet Firewall?
The Router has easily customizable filter sets that you can use
to set it up as an Internet Firewall. To do this, set the
filters to do the following:
Allow ARP/ICMP/PING packets
Allow TCP/UDP traffic to ports > 1023
Allow HTTP, SMTP, NNTP, DNS
Block everything else inbound from the Internet
Here's an example in Router:
A branch office wants to allow all Packet from headquarter
through Internet, but would like to setup a Internet firewall to
block other intrusion:
a. Allow all packets from headquarter 192.168.1.0/24 network
Menu 21.1.1 - TCP/IP Filter Rule
Filter #: 1,1
Filter Type= TCP/IP Filter Rule
Active= Yes
IP Protocol= 0 IP Source Route= No
Destination: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 0
Port # Comp= None
Source: IP Addr= 192.168.1.0
IP Mask= 255.255.255.0
Port #= 0
Port # Comp= None
TCP Estab= N/A
More= No Log= None
Action Matched= Forward
^^^^^^^^
Action Not Matched= Check Next Rule
b. Allow ICMP (including PING)
Menu 21.1.2 - TCP/IP Filter Rule
Filter #: 1,2
Filter Type= TCP/IP Filter Rule
Active= Yes

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 4
IP Protocol= 1 IP Source Route= No
^^^^^^^^^^^^^^^
Destination: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 0
Port # Comp= None
Source: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 0
Port # Comp= None
TCP Estab= N/A
More= No Log= None
Action Matched= Forward
^^^^^^^^
Action Not Matched= Check Next Rule
c. Allow UDP traffic to ports > 1023
Menu 21.1.3 - TCP/IP Filter Rule
Filter #: 1,3
Filter Type= TCP/IP Filter Rule
Active= Yes
IP Protocol= 17 IP Source Route= No
^^^^^^^^^^^^^^^
Destination: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 1023
^^^^
Port # Comp= Greater
^^^^^^^
Source: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 0
Port # Comp= None
TCP Estab= N/A
More= No Log= None
Action Matched= Forward
^^^^^^^
Action Not Matched= Check Next Rule
d. Allow TCP for ports > 1023, and drop all other packets.
Menu 21.1.4 - TCP/IP Filter Rule
Filter #: 1,4
Filter Type= TCP/IP Filter Rule
Active= Yes
IP Protocol= 6 IP Source Route= No
^^^^^^^^^^^^^^^
Destination: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 1023
^^^^
Port # Comp= Greater

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 5
^^^^^^^
Source: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 0
Port # Comp= None
TCP Estab= No
More= No Log= None
Action Matched= Forward
^^^^^^^
Action Not Matched= Drop <== This is IMPORTANT!!
^^^^
e. The Menu 21.1 will look like
Menu 21.1 - Filter Rules Summary
# A Type Filter Rules M m n
- - ---- ------------------------------------------------------------------- - - -
1 Y IP Pr=0, SA=192.168.1.0, DA=0.0.0.0 N F N
2 Y IP Pr=1, SA=0.0.0.0, DA=0.0.0.0 N F N
3 Y IP Pr=17, SA=0.0.0.0, DA=0.0.0.0, DP>1023 N F N
4 Y IP Pr=6, SA=0.0.0.0, DA=0.0.0.0, DP>1023 N F D
5 N
6 N
f. Plug it to Menu 11.1 Input Filter Sets.
g. If you have any server application running inside of your
network, such as Domain Name Server, then you need to insert
another filter before rule 4. For DNS, the filter rule will
look like the following:
Menu 21.1.4 - TCP/IP Filter Rule
Filter #: 1,4
Filter Type= TCP/IP Filter Rule
Active= Yes
IP Protocol= 17 IP Source Route= No
^^^^^^^^^^^^^^^
Destination: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 53
^^
Port # Comp= Equal
^^^^^
Source: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 0
Port # Comp= None
TCP Estab= No
More= No Log= None
Action Matched= Forward
^^^^^^^
Action Not Matched= Check Next Rule
h. The your Menu 21.1 will look like

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 6
Menu 21.1 - Filter Rules Summary
# A Type Filter Rules M m n
- - ---- ------------------------------------------------------------------- - - -
1 Y IP Pr=0, SA=192.168.1.0, DA=0.0.0.0 N F N
2 Y IP Pr=1, SA=0.0.0.0, DA=0.0.0.0 N F N
3 Y IP Pr=17, SA=0.0.0.0, DA=0.0.0.0, DP>1023 N F N
4 Y IP Pr=17, SA=0.0.0.0, DP=53, DA=0.0.0.0 N F N
5 Y IP Pr=6, SA=0.0.0.0, DA=0.0.0.0, DP>1023 N F D
6 N
i. Sometimes Internet application such as vedio conference need to
use the UDP server port, then you have to be careful in setting
up the firewall filter.
4. How do I configure the Router as a Remote Access Server?
Configuring the Router is made simple by the SMT (System Management Terminal), a menu
driven user interface. To configure the Router for use as a Remote Access Server, follow these
steps.
4.a Windows 95 Remote User
Configure all the necessary parameters in Menu 13 for the Windows 95 Remote User. Then add a
Remote User by configuring Menu 14. For a more detailed description of these Menus, please see
the Router User's Manual.
4.b Other PPP Packages
The Router is compatible with many other PPP packages running in various platforms such as
Windows 3.1x, Mac, Unix. Please check with D-Link on the compatibility list.
5. How do I configure my Router for my applications?
5.a Internet Access
My-net
|
O--|
|---[Router]---------( ISP )
O--| ^ ^ ^
| A A C
The Router can allow multiple hosts on the LAN (My-net) to access the Internet through an ISP
(Internet Service Provider). In this configuration, the Router is assigned a unique Ethernet IP
address on ‘My-net’ (A). This address (A) will be also used to negotiate the connection with the
ISP. Note that the IP address on ‘My-net’ are not hidden from the ISP and the rest of the Internet.
In Menu 1:
-Set Route IP to ‘Yes’.
In Menu 3.2:
- Set IP Address to an address on ‘My-net’ (A).
In Menu 4:
- Set ISP IP Addr to ‘C’.

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 7
- Make sure Single User Account is set to ‘No’.
In order for the nodes on ‘My-net’ to access the Internet, they
need to have two items configured. First, the should set their
‘default gateway’ to the IP address of the Router (A). Second,
they need to set their Domain Name Server address. If the LAN
has a DNS present, use this address. Otherwise, you will have to
obtain the DNS IP address from the ISP (not C).
5.b Internet Access with SUA
My-net
|
O--|
|---[Router]---------(ISP)
O--| ^ ^ ^
| A B C
The Router allows multiple hosts on the LAN (My-net) to share a
single IP address in the Internet. This address will be assigned
by your ISP and is indicated in the above diagram by ‘B’. Note
that the IP addresses on ‘My-net’ are hidden from the ISP and the
rest of the Internet.
In Menu 1:
- Set Route IP to ‘Yes’.
In Menu 3.2:
- Set IP Address to an address on ‘My-net’ (A).
In Menu 4:
- Set ISP IP Addr to ‘C’.
- Set Single User Account to ‘Yes’.
- Set Single User Account: IP Addr to ‘B’. If the ISP
assigns this address dynamically, leave this field blank or
enter ‘0.0.0.0’
- Set Single User Account: Server IP Addr to the IP address
of a server station on ‘My-net’. If the LAN has a Domain Name
Server (DNS) station on it, the IP address of that station
must be entered in this field (otherwise, this field is not
required).
In order for the nodes on ‘My-net’ to access the Internet, they
need to have two items configured. First, the should set their
‘default gateway’ to the LAN IP address of the Router (A).
Second, they need to set their Domain Name Server address. If
the LAN has a DNS present, use this address. Otherwise, you will
have to obtain the DNS IP address from the ISP (not C).
5.c LAN to LAN for TCP/IP
My-net Rem-net
| |
O--| |--O
|---[Router]-----------[ISDN Router]---|
O--| ^ ^ |--O

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 8
| A B |
The Router can allow multiple hosts on the LAN (My-net) to access
a remote network’s resources. In this configuration, the Router
is assigned a unique Ethernet IP address on ‘My-net’ (A).
Similarly, the remote ISDN router is issued a unique Ehternet IP
address on ‘Rem-net’ (B). These addresses (A and B) will be also
used to negotiate the connection between ‘My-net’ and ‘Rem-net’.
In Menu 1:
- Set Route IP to ‘Yes’.
In Menu 3.2:
- Set IP Address to an address on ‘My-net’ (A).
In Menu 11.1:
- Set Route to ‘IP’.
- Set Rem IP Addr to the IP address of the remote ISDN router
(B).
- Select ‘Yes’ to editing the IP options.
In Menu 11.3:
- Set Rem Subnet Mask to the subnet mask for the remote
network.
The remote ISDN router (Cisco, Ascend...etc.) will have to
complete similar configuration changes in order to talk to the
Router.
5.d LAN to LAN for IPX
1. Router on the NetWare server side
My-net Rem-net
| |
O--| |--O
|---[Router]-----------[ISDN Router]---|
O--| ^ ^ |--O
^ | A B | ^
| |
NetWare NetWare
Server Client
The Router can accept calls from a remote router to
negotiate IPX routing. In this configuration, the stations
on the remote network (Rem-net) will have access to the IPX
network resources available on ‘My-net’ and vice versa.
In Menu 1:
- Set Route IPX to ‘Yes’.
In Menu 3.3:
- Determine what frame type the client and server(s)
stations are using and set the appropriate frame type
to ‘Yes’. The Router will not be able to
communicate with the nodes unless the frame types are
the same.

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 9
- Set Seed Router to ‘No’. The Router will obtain the
network numbers from the RIP broadcasts across the
LAN.
In Menu 11.1:
- Set Call Direction to ‘Incoming’.
- Set Route to ‘IPX’, and select ‘Yes’ to editing the
IPX options.
In Menu 11.3:
- Set Dial-On-Query to ‘No’.
- Set Rem LAN Net # to the external network number of
the remote network (B).
The remote ISDN router (Cisco, Ascend...etc.) will have to
complete similar configuration changes in order to talk to
the Router.
2. Router on the NetWare client side
My-net Rem-net
| |
O--| |--O
|---[Router]-----------[ISDN Router]---|
O--| ^ ^ |--O
^ | A B | ^
| |
NetWare NetWare
Client Server
The Router can place calls to a remote ISDN router to
negotiate IPX routing. In this configuration, the stations
on the LAN (My-net) will have access to the IPX NetWare
server and other network resources available on ‘Rem-net’
and vice versa. Note that in this setup, there is no
NetWare server on ‘My-net’.
In Menu 1:
- Set Route IPX to ‘Yes’.
In Menu 3.3:
- Determine what frame type the client station(s) are
using and set the appropriate frame type to ‘Yes’.
The Router will not be able to communicate with the
nodes unless the frame types are the same.
- Set Seed Router to ‘Yes’.
In Menu 11.1:
- Set Call Direction to ‘Outgoing’.
- Set Route to ‘IPX’, and select ‘Yes’ to editing the
IPX options.
In Menu 11.3:
- Set Dial-On-Query to ‘Yes’.
- Set Rem LAN Net # to the internal network number of
the remote NetWare server.

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 10
The remote ISDN router (Cisco, Ascend...etc.) will have to
complete similar configuration changes in order to talk to
the Router.
3. NetWare servers on both sides of the link
My-net Rem-net
| |
O--| |--O
|---[Router]-----------[ISDN Router]---|
O--| ^ ^ |--O
^ | A B | ^
| |
NetWare NetWare-+
Server = Server_1 Server = erver_2
Net number = 111 Net number = 222
The Router can place calls to a remote ISDN router to
negotiate IPX routing. In this configuration, the stations
on the LAN (My-net) will have access to the IPX NetWare
server on their own network. If the client stations on
‘My-net’ want to access the remote NetWare server
(Server_2), then they will need to configure a static route
for that Router.
In Menu 1:
- Set Route IPX to ‘Yes’.
In Menu 3.3:
- Determine what frame type the client station(s) are
using and set the appropriate frame type to ‘Yes’.
The Router will not be able to communicate with the
nodes unless the frame types are the same.
- Set Seed Router to ‘No’.
In Menu 11.1:
- Set Call Direction to ‘Outgoing’.
- Set Route to ‘IPX’, and select ‘Yes’ to editing the
IPX options.
In Menu 11.3:
- Set Dial-On-Query to ‘Yes’.
- Set Rem LAN Net # to the external network number of
the remote network (B).
In Menu 12.2
- Set Server Name to ‘Server_2’ (The name configured
for the server).
- Set Active to ‘Yes’.
- Set Network # to ‘00000222’ (The internal network
number of the server).
- Set Gateway Node to the number of the remote node (1-
4) for this setup.
The remote ISDN router (Cisco, Ascend...etc.) will have to
complete similar configuration changes in order to talk to
the Router.

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 11
5.e Bridging IPX
1. Router on the NetWare server side
My-net Rem-net
| |
O--| |--O
|---[Router]-----------[ISDN Router]---|
O--| |--O
^ | | ^
| |
NetWare NetWare
Server Client
The Router can accept calls from a remote router to Bridge
IPX packets. In this configuration, the stations on the
remote network (Rem-net) will have access to the IPX
network resources available on ‘My-net’.
In Menu 1:
- Set Bridge to ‘Yes’.
In Menu 3.4:
- Set Handle IPX to ‘Server’.
In Menu 11.1:
- Set Call Direction to ‘Incoming’.
- Set Bridge to ‘Yes’.
- Select ‘Yes’ to editing the Bridge options.
In Menu 11.3:
- Set Dial-On-Broadcast to ‘No’.
The remote ISDN router (Cisco, Ascend...etc.) will have to
complete similar configuration changes in order to talk to
the Router.
2. Router on the NetWare client side
My-net Rem-net
| |
O--| |--O
|---[Router]-----------[ISDN Router]---|
O--| |--O
^ | | ^
| |
NetWare NetWare
Client Server
The Router can place calls to a remote ISDN router to
Bridge IPX packets. In this configuration, the stations on
the LAN (My-net) will have access to the IPX NetWare server
and other network resources available on ‘Rem-net’. Note
that in this setup, there is no NetWare server on ‘My-net’.

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 12
In Menu 1:
- Set Bridge to ‘Yes’.
In Menu 3.4:
- Set Handle IPX to ‘Client’.
In Menu 11.1:
- Set Call Direction to ‘Outgoing’.
- Set Bridge to ‘Yes’.
- Select ‘Yes’ to editing the Bridge options.
In Menu 11.3:
- Set Dial-On-Broadcast to ‘Yes’.
The remote ISDN router (Cisco, Ascend...etc.) will have to
complete similar configuration changes in order to talk to
the Router.
5.f Windows 95/NT Dialing in for TCP/IP
My-net
|
O--|
|---[Router]---------[ISDN TA]---O
O--| ^ ^ ^ ^
| A A C Win 95/NT
The Router can accept calls from a remote station equipped with
remote access software (such as Windows 95 Dial-Up Networking).
The remote station uses an ISDN terminal adapter to make the
connection. In this configuration, the remote station will have
access to the TCP/IP network resources available on ‘My-net’.
There are two ways to set the IP address for the remote station
(C). This can be set statically set by the remote station, or it
can be dynamically set by the Router.
In Menu 1:
- Set Route IP to ‘Yes’.
In Menu 3.2:
- Set IP Address to an address on ‘My-net’ (A).
In Menu 13:
- Set Recv Authen. to PAP.
- Set Dial-in User to ‘Yes’ if the remote station will
provide its own IP address (C). Otherwise, set to ‘No’.
- Set IP Pool to ‘Yes’ if you want the Router to assign an
IP address to the remote station.
If you are using the IP Pool:
- Set IP Start Addr as IP address assigned to the remote
station (C).
- Set IP Count(1,2) to be the number of IP addresses in the
pool.
In Menu 14.1:

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 13
- Set User Name to be the login name for the remote station.
- Set Passwd to be the password for the remote station.
5.g Windows 95/NT Dialing in for IPX
My-net
|
O--|
|---[Router]---------[ISDN TA]---O
O--| ^ ^
^ | C Win 95/NT
|
NetWare
Server
The Router can accept calls from a remote station equipped with
remote access software (such as Windows 95 Dial-Up Networking).
The remote station uses an ISDN terminal adapter to make the
connection. In this configuration, the remote station will have
access to the IPX network resources available on ‘My-net’. There
are two ways to set the external network number for the remote
station. It can be set provided by the Router from a pool, or it
can be generated randomly.
In Menu 1:
- Set Route IPX to ‘Yes’.
In Menu 3.3:
- Determine what frame type the client and server(s) stations
are using and set the appropriate frame type to ‘Yes’. The
Router will not be able to communicate with the nodes
unless the frame types are the same.
- Set Seed Router to ‘No’. The Router will obtain the
network numbers from the RIP broadcasts across the LAN.
In Menu 13:
- Set IPX Pool to ‘Yes’ if you want the Router to assign a
pre-configured IPX network number to the remote station.
Otherwise, the Router will generate a random network
number for the remote station.
If you are using the IPX Pool:
- Set IPX Start Net Num. as the starting IPX network number
you wish to assign to the remote station (C).
- Set IPX Count(1,16) to be the number of IPX network numbers
in the pool.
In Menu 14.1:
- Set User Name to be the login name for the remote station.
- Set Passwd to be the password for the remote station.
6. How do I configure my Router to work with other devices?
Cisco Router

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 14
My-net Rem-net
| |
O--| |--O
|---[Router]-----------[Cisco Router]---|
O--| |--O
| |
Due to Cisco’s authentication scheme, you need to configure some
additional fields when talking to a Cisco device. There are two
instances to pay attention to. The first is Cisco’s mutual
authentication scheme, and the second is their interpretation of
CHAP.
If the Cisco router requests PAP:
In Menu 13:
- Set Mutual Authen to ‘Yes’.
- Set PAP Login to the appropriate login name.
- Set PAP Password to the appropriate login password.
If the Cisco router requests CHAP:
Note: The Cisco device must be configured as a remote node and
not a remote user.
In Menu 11.1 (only if Call Direction is ‘Incoming’ or ‘Both’):
- Set Incoming: Rem Login to the Cisco device hostname.
- Set Outgoing: My Login to the System Name value in menu 1.
- Set Incoming: Rem Password to be the same as Outgoing: My
Password.
7. How can I protect against IP spoofing attacks?
The Router’s filter sets provide a means to protect against IP
spoofing attacks. The basic scheme is as follows:
For the incoming data filters:
- Deny packets from the outside that claim to be from the inside
- Allow everything that isn't spoofing us
Filter Type= TCP/IP Filter Rule
Active= Yes
Source: IP Addr= a.b.c.d
Source: IP Mask= w.x.y.z
Action Matched= Drop
Action Not Matched= Forward
where a.b.c.d is an IP address on your local network and w.x.y.z
is your netmask
For the outgoing data filters:
- Deny "bounceback" packets
- Allow packets that originate from us
Filter Type= TCP/IP Filter Rule
Active= Yes
Destination: IP Addr= a.b.c.d
Destination: IP Mask= w.x.y.z

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 15
Action Matched= Drop
Action Not Matched= Forward
where a.b.c.d is an IP address on your local network and w.x.y.z
is your netmask
8. I want to assign an IP address to my workstation
dynamically...how?
The Router can assign IP addresses during the IPCP negotiation,
but that only applies to the device that's calling in, either a
remote router or a remote workstation with a TA. The Router
cannot assign IP addresses to any workstations behind the router,
because nothing on that workstation performing the IPCP
negotiation.
In the case of a workstation calling in using an ISDN TA, the
Router is able to assign the IP address because it is the
workstation that is doing the actual PPP/IPCP negotiation.
9. How can I prevent incoming telnet sessions to my Router?
The Router has implemented a telnet password, which must be
entered before a telnet session is established. This password is
the same as the system password configured in menu 23. In
addition, the Router will only allow one administrator to
configure the device at a time. Any attempted telnet session
will be rejected if an administrator is already logged into the
SMT.
If you want to block all incoming telnet sessions from being
established, you can define an IP filter and plug it into the
incoming data filters for appropriate remote connection:
Filter Type= TCP/IP Filter Rule
Active= Yes
IP Protocol= 6
Destination: IP Addr= w.x.y.z
Destination: IP Mask= 255.255.255.255
Destination: Port #= 23
Destination: Port # Comp= Equal
Action Matched= Drop
Action Not Matched= Forward
where w.x.y.z is the IP address of your Router.
10. How can I backup/restore my configuration remotely?
Currently, the only method available for backing up and restoring
the Router’s configuration is locally through the RS-232 port.
Menu 24.5 and 24.6 provide simple methods to perform the backup
and restoration.
11. How do I enable DOVBS when I make an outcall?
You can enable DOVBS (Data Over Voice Barrier Service) can be

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 16
enabled in menu 11. When you configure your remote node to make
an outcall, set the ‘Telco Option: Transfer Rate’ field to
‘DOVBS’. If you check the system status menu (24.1) the
connection Type should be 56K.
The Router can automatically detect an incoming DOVBS call. Once
the call is connected, menu 24.1 will also indicate a Type of
56K.
12. How I can prevent any packets from triggering a call?
For those customers that pay by the call, and not the minute,
they can set up a call filter to stop packets from triggering the
call. Set the destination IP address to 0.0.0.0 (filter ALL
packets). Also set the Idle Timeout of that remote node to zero.
To trigger the call in this scenario, use the option in menu
24.4.5 (manual call). This way, the call will never time out but
it will also never automatically dial either.
13. How can I turn on call tracing tools?
For call setup EPA trace:
. Go to CI (Menu 24.8) issue ‘isdn ana on’ command
. make a call
. after the call failed (disconnected), issue ‘isdn ana off’
and ‘isdn ana disp’ (You have to do this in RS-232
connection, and use the PgDn in number keypad to scroll the
trace)
For PPP trace:
. Go to CI, ‘sys trcl cl’ and then ‘sys trcl sw on’, ‘sys trcp
sw on’
. make a call
. ‘sys trcl disp’ to display the traces
14. How can I configure the correct default static route for my
Router?
You can do this by configuring an IP static route in menu 12.
The Destination IP Address for this route should be ‘0.0.0.0’.
Once this has been configured, the default route should be stored
correctly.
15. How do I setup the Router to make MP calls?
By default, the Router is set to only make single link calls
(using 1 B-channel). You can configure your Router to make an MP
call by setting some parameters for that Remote Node. When you
get to the Remote Node configuration screen, select ‘Yes’ to Edit
the PPP options. There are two ways to setup the MP call:
a. Set Base Trans Rate to ‘128’. This will bring up both
channels every time the call is placed.
b. Set Base Trans Rate to ‘64’ and Max Trans Rate to ‘128’.
This will bring up the second B-channel based on the traffic

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 17
across the link. Please see the manual for more information.
16. How do I block Win95 or NT’s NetBEUI over IP packets from
triggering a call to my ISP?
Setup a filter set as follows, and plug it in Menu 11 for the ISP
remote node in the ‘Call filter sets=’.
Menu 21.1 - Filter Rules Summary
# A Type Filter Rules M m n
- - ---- -------------------------------------------------- - - -
1 Y IP Pr=17, SA=0.0.0.0, SP=138, DA=0.0.0.0 N D N
2 Y IP Pr=17, SA=0.0.0.0, SP=137, DA=0.0.0.0 N D F
3 Y IP Pr=6, SA=0.0.0.0, SP=138, DA=0.0.0.0 N D N
4 Y IP Pr=6, SA=0.0.0.0, SP=137, DA=0.0.0.0 N D F
5 N
6 N
Menu 21.1.1 - TCP/IP Filter Rule
Filter #: 1,1
Filter Type= TCP/IP Filter Rule
Active= Yes
IP Protocol= 17 IP Source Route= No
Destination: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 0
Port # Comp= None
Source: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 138
Port # Comp= Equal
TCP Estab= N/A
More= No Log= None
Action Matched= Drop
Action Not Matched= Check Next Rule
Menu 21.1.2 - TCP/IP Filter Rule
Filter #: 1,2
Filter Type= TCP/IP Filter Rule
Active= YesIP Protocol= 17 IP Source Route= No
Destination: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 0
Port # Comp= None
Source: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 137
Port # Comp= Equal
TCP Estab= N/A
More= No Log= None
Action Matched= Drop

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 18
Action Not Matched= Forward
Menu 21.1.2 - TCP/IP Filter Rule
Filter #: 1,3
Filter Type= TCP/IP Filter Rule
Active= YesIP Protocol= 6 IP Source Route= No
Destination: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 0
Port # Comp= None
Source: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 138
Port # Comp= Equal
TCP Estab= N/A
More= No Log= None
Action Matched= Drop
Action Not Matched= Check Next Rule
Menu 21.1.2 - TCP/IP Filter Rule
Filter #: 1,4
Filter Type= TCP/IP Filter Rule
Active= YesIP Protocol= 6 IP Source Route= No
Destination: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 0
Port # Comp= None
Source: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 137
Port # Comp= Equal
TCP Estab= N/A
More= No Log= None
Action Matched= Drop
Action Not Matched= Forward
Part III: Troubleshooting Questions
1. My connection won’t stay down. How can I prevent this?
The Router comes with several pre-defined call filters designed
to prevent certain IPX packets from triggering a call to a remote
node. These filters should inform your Router which packets
should be ignored as traffic.
If you are routing IPX packets, the default call filters are
defined as follows:

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 19
- Block periodical SAP and RIP response messages
- Block NetWare serialization packets
- Allow SAP and RIP enquery packets
If you are bridging IPX packets, the default call filters are
defined as follows:
- Block periodical SAP and RIP response messages
- Block SAP and RIP enquery packets if set to Handle IPX as
‘Server’
- Allow SAP and RIP enquery packets if set to Handle IPX as
‘Client’ or ‘None’
If you want to prevent packets from other protocols from
triggering the call, you can block an entire protocol type by
setting up a generic filter rule in the following way:
Filter Type= Generic Filter Rule
Active= Yes
Offset= 12
Length= 2
Mask= ffff
Value= [protocol ID]
More= No
Action Matched= Drop
Action Not Matched= Forward
If your filtering scheme requires you to block more specific
packets, you can determine the type of packet that is triggering
your call by looking in menu 24.1. First drop your connection,
and then stop all data traffic. The line should stay idle. If
the call is still triggered, then you can check menu 24.1, and by
looking at the packet format, you can adjust your filter set
accordingly to block these packets.
2. Why does the Router still drop the call after the authentication
has passed?
In some cases, when you are negotiating a connection, you may
notice that the call will be dropped even though the CHAP or PAP
authentication phase was successful. The reason for this may be
because the IPCP negotiation has failed due to an IP address
mismatch. The Router uses the IP address as another form of
authentication, so if the address supplied by the remote node
does not match the address the Router is expecting, the call will
be dropped.
3. Why does my screen keep blanking out?
In both an RS-232 connection and a telnet session, the SMT
(System Management Terminal) has a system timeout of five
minutes. That is, if you do not perform a keyboard operation in
five minutes then the screen will blank out or your telnet
connection will be dropped. You can disable this timeout by
going into CI mode, and typing the command: sys stdio 0

D-Link Co.,_______________________________________________________________________ FAQ
FAQ: 20
4. Will my screen blank out if I stay in menu 24.1?
No. If you keep your system on menu 24.1, the system will not
timeout after the five minutes has elapsed.
5. What can I do if I don’t know the IP address of the device I am
connecting to?
In some cases, your Internet Service Provider (ISP) or other
remote node you wish to connect to will not know their IP
address.
You can work around this problem by using the Internet Setup Menu
(menu 4) to configure your remote node. In this screen, you have
the option to leave the ISP’s IP address field blank or simply
enter 0.0.0.0. In these cases, the Router will accept any IP
address sent from that device.
If you want the remote device to dynamically assign an IP to the
Router, then you need to turn on the Single User Account feature,
and leave the IP Addr field blank or filled with 0.0.0.0.
6. Why do I see garbage characters being printed out on my console?
This condition is due to data overflowing the UART. You may not
have a 16650 UART chip on your serial port, or you might not have
flow control working correctly on that port. There is no harm
caused by this data overflow. You can repaint the screen by
escaping back one menu and then re-entering the screen.
7. My Router inexplicably reboots itself. Why?
The could be a problem with the power supply connection on the
rear panel of the Router. The connection may be loose and
causing the Router to reboot itself. When you plug in the power
cable, make sure that you apply the force behind the sliding
collar and not holding it. This will ensure a good connection.
To test if the connection is firm, hold the back of the power
cable plug, just behind the sliding collar, and try pulling the
cable out. If the connection is firm, you should not be able to
pull the cable out without pulling the sliding collar back.
8. Why can’t I get the callback feature to work when I dial from a
workstation to the Router?
Router only supports Microsoft's proprietary CallBack Control
Protocol (CBCP). Thus, the Router will only be able to do PPP
callback to other devices that also support CBCP, such as Win95
or NT. If you are using Trumpet or other application that
doesn’t support CBCP, Router will not callback.
9. Dial-in users to the Router cannot talk to some or all of the
stations on the LAN side of Router, or access Internet through
another router on the LAN (Dial-in user are using IP address in
IP pool) Why?