Cisco 3640 Series User manual

Modem over ISDN BRI for the Cisco 3640 Router 1
Modem over ISDN BRI for the
Cisco 3640 Router
Feature Summary
The Modem over Integrated Services Digital Network (ISDN) Basic Rate Interface (BRI) feature for
the Cisco 3640 modular access router lowers the cost of remote access by offering high-speed
modem and ISDN connectivity for mobile customers, home-offices, and other remote-access users.
Branch offices and enterprises can support analog modem users who call over the public switched
telephone network (PSTN) into BRI interfaces in Cisco 3640 routers.
Analog modem calls arrive at a speed of 33.6 kilobits per second (kbps) via the PSTN. The router’s
digital modems accept the modem calls at connection speeds as fast as 56 kbps, adhering to the V.90
standard. As shown in Figure 1, the Cisco 3640 router in this way provides rapid access to email and
other network services.
Figure 1 Modem over ISDN BRI Feature
BRI
Cisco 3640 router with 4- or 8-port
module and internal digital modems
POTS
lines
Optional WAN to
headquarters
Ethernet
Home office
Small business
Mobile
PSTN
17271

Feature Summary
2Cisco IOS Release 12.0(3)T
Benefits The following are benefits of using Modem over ISDN BRI:
•Supports cost-effective and readily available BRI service
•Provides remote modem users with rapid Internet and LAN/WAN access
•Allows flexible remote access application support
List of Terms
BRI—Basic Rate Interface. ISDN interface composed of two B channels and one D channel for
circuit-switched communication of voice, video, and data.
ISDN—Integrated Services Digital Network. Communication protocol, offered by telephone
companies, that permits telephone networks to carry data, voice, and other source traffic.
NM—network module.
POTS—Plain Old Telephone Service. Basic telephone service supplying standard single-line
telephones, telephone lines, and access to the public switched telephone network.
PRI—Primary Rate Interface. ISDN interface to primary rate access. Primary rate access consists
of a single 64-Kbps D channel plus 23 (T1) or 30 (E1) B channels for voice or data.
PSTN—public switched telephone network. PSTN refers to the local telephone company.
SPID—service profile identifier. Number that some service providers use to define the services to
which an ISDN device subscribes. The ISDN device uses the SPID when accessing the switch that
initializes the connection to a service provider.
TEI—terminal endpoint identifier. In ISDN, a number that identifies a specific connection endpoint
within a service access point.
VIC—voice interface card.
WIC—wide-area network (WAN) interface card.
RestrictionsThis feature requires specific hardware and software:
•At least one of the digital modem network modules listed below—the number in the model name
indicates the number of digital modems that can be connected to the module.
—NM-6DM
—NM-12DM
—NM-18DM
—NM-24DM
—NM-30DM
These digital modem network modules do not have their own network connections, but instead
handle analog calls passing through other router interfaces. BRI modules can provide their ISDN
connectivity. Other modules, such as Ethernet, can provide connectivity to the LAN. The digital
modem module acts as a pool of available modems that can be used for both incoming and
outgoing calls. Digital modem network modules do not support BRI VIC or WIC interfaces.

Restrictions
Modem over ISDN BRI for the Cisco 3640 Router 3
•At least one of the following Cisco BRI network modules:
—NM-4B-S/T—Four-port ISDN BRI network module, minimum version 800-01236-03
—NM-4B-U—Four-port ISDN BRI with integrated NT-1 network module, minimum version
800-01238-06
—NM-8B-S/T—Eight-port ISDN BRI network module, minimum version 800-01237-03
—NM-8B-U—Eight-port ISDN BRI with integrated NT-1 network module, minimum version
800-01239-06
The version level is available from the show diag command, which displays the version number
as the part number. If your BRI network module is a version lower than those cited above or you
need more details, see the Cisco Connection Online (CCO) Field Notice titled Using Digital
Modems with the Cisco 3600 Basic Rate Interface (BRI) Network Module Upgrade in the Access
Products index. If your existing Cisco BRI network module is one of those listed above and does
not support the Modem over ISDN BRI feature, Cisco will upgrade the module at no charge.
•To support the Modem over ISDN BRI feature, V.90 modem portware—for instructions on
downloading this software or obtaining it otherwise, see the Cisco 3600 Series Modem Portware
Upgrade Configuration Note on CCO.
PlatformsThis feature is supported on the Cisco 3640 router.
Note Due to Cisco 3620 slot limitations, the Modem over ISDN BRI feature is not supported on
the Cisco 3620 router.
Prerequisites
Before you can configure a Cisco 3640 router to provide Modem over ISDN BRI connectivity, you
must perform the tasks listed below:
•Obtain BRI service from your telecommunications provider. The BRI line must be provisioned
at the switch to support voice calls.
•Install a four-port or eight-port BRI network module into your Cisco router. Depending on the
type of network module and your BRI service, you might also need to install an external network
terminator (NT-1).
•Install a supported digital modem network module into the Cisco 3640 router.
•After the system comes up, make sure enough buffers are in the free list of the buffer pool that
matches the maximum transmission unit (MTU) of your BRI interface. If not, you must
reconfigure buffers so the BRI interfaces function properly. To check the MTU of your interfaces,
use the show interfaces bri command. The show buffers command displays the free buffer
space. Use the buffers global configuration command to make adjustments to initial buffer pool
settings and to the limits at which temporary buffers are created and destroyed.

Supported MIBS and RFCs
4Cisco IOS Release 12.0(3)T
For details about software configuration, see the Cisco IOS Release 12.0 software document, Dial
Solutions Configuration Guide. For more information about the physical characteristics of the BRI
network modules and their digital modem support, or instructions on how to install the network or
modemmodules,eitherseetheCisco3600seriesNetworkModuleHardware Installation Guide that
came with your BRI network module or view the up-to-date information on CCO.
Supported MIBS and RFCs
None.
Configuration Tasks
The Modem over ISDN BRI feature is part of interface configuration for BRI. You configure the BRI
interface after you have configured the ISDN global characteristics, which are switch type and TEI
negotiation timing. These characteristics can also be defined for each BRI interface, as shown in the
steps below. For details on the global and interface configuration commands, see the Cisco IOS
software document, Dial Solutions Configuration Guide.
To set up the BRI interface characteristics, set the global parameters and then configure each
interface separately. Perform the following configuration tasks:
Step Command Purpose
1Router(config)#isdn switch-type
switch-type
Configure the global ISDN switch type
to match the service provider switch
type. For a list of keywords, refer to
Table 1.
2Router(config)#isdn tei [first-call |
powerup]Configure when the ISDN Terminal
Endpoint Identifier (TEI) negotiation
occurs. If this command is not used,
negotiation occurs when the router is
powered on.
The first-call option is primarily used
in European ISDN switch types, such as
NET3 networks. The powerup option
should be used in most other locations.
3Router(config-if)#interface bri
slot/port
Enter interface configuration mode to
configure parameters for the specified
interface.
slot is the location of the BRI module.
Valid values are from 0 to 3.
port is an interface number. Valid
values are from 0 to 7 if the module is
an eight-port BRI network module, or
from 0 to 4 if the module is a four-port
BRI network module.
4Router(config-if)#ip address
ip-address
mask
Specify an IP address and subnet for the
interface. You can also specify that
there is no IP address. For information
about IP addressing, see the IOS
software document, Network Protocols
Configuration Guide, Part 1.

Restrictions
Modem over ISDN BRI for the Cisco 3640 Router 5
5Router(config-if)#encapsulation ppp Enable Point-to-Point Protocol (PPP)
encapsulation on the BRI interface. PPP
encapsulation is configured for most
ISDN communication.
If the router needs to communicate with
devices that require a different
encapsulation protocol, needs to detect
encapsulation on incoming calls
automatically, or needs to send traffic
over a Frame Relay or X.25 network,
see the Cisco IOS software document,
Dial Solutions Configuration Guide.
6Router(config-if)#dialer map
protocol
next-hop-address name hostname speed 56|64
dial-string [: isdn-subaddress ]
Router(config-if)#dialer map protocol
next-hop-address name hostname spc [speed
56 |64] [broadcast]
dial-string [: isdn-subaddress ]
(Optional, Most locations) Define the
remote recipient’s protocol address,
host name, and dialing string;
optionally, provide the ISDN
subaddress; set the dialer speed to 56 or
64 kbps, as needed.
or
(Optional,Germany) Use the command
keyword that enables ISDN
semipermanent connections.
7Router(config-if)#dialer-group
group-number
(Optional) Assign the interface to a
dialer group to control access to the
interface.
8Router(config-if)#dialer-list
dialer-group list access-list-number
(Optional) Associate the dialer group
number with an access list number.
9Router(config-if)#access-list
access-list-number {deny | permit}
protocol source address source-mask
destination destination-mask
(Optional) Define an access list
permitting or denying access to
specified protocols, sources, or
destinations. Permitted packets cause
the router to place a call to the
destination protocol address.
10 Router(config-if)#no ip-directed
broadcast (Optional) Disable the translation of
directed broadcast to physical
broadcasts.
11 Router(config-if)#isdn switch-type
switch-type
(Optional) Configure the interface
ISDN switch type to match the service
provider switch type. The interface
ISDN switch type overrides the global
ISDN switch type on the interface.
For a list of keywords, refer to Table 1.
12 Router(config-if)#isdn tei [first-call |
powerup](Optional) Determine when ISDN TEI
negotiation occurs for an individual
interface. This overrides the global
configuration command.
Step Command Purpose

Configuration Tasks
6Cisco IOS Release 12.0(3)T
13 Router(config-if)#isdn spid1
spid-number
[ ldn ]Specify a SPID and local directory
number for the B1 channel. Currently,
only the DMS-100 and NI-1 switch
types require SPIDs. Although the
5ESS switch type might support a
SPID, we recommend that you set up
that ISDN service without SPIDs.
14 Router(config-if)#isdn spid2
spid-number
[ ldn ]Specify a SPID and local directory
number for the B2 channel.
15 Router(config-if)#isdn caller
number
(Optional) Configure caller ID
screening.
16 Router(config-if)#isdn answer1
[
called-party-number ]
[: subaddress ]
(Optional) Configure called-party
number verification for a called-party
number or subaddress number in the
incoming setup message.
17 Router(config-if)#isdn calling-number
calling-number
(Optional) Specify the calling-party
number.
18 Router(config-if)#isdn not-end-to-end [56
|64](Optional) Configure the speed for
incoming calls not recognized as ISDN
end-to-end.
19 Router(config-if)#isdn incoming-voice
modem Route incoming voice calls to the
modem and treat them as analog data.
This step is required for the Modem
over ISDN BRI feature.
20 Router(config-if)#isdn modem-busy-cause
{
number |busy |not available}(Optional) Specify the message that is
returned when no modem is available
for a call. This command is optional for
the Modem over ISDN BRI feature.
number is a 1- to 3-digit number. Valid
values are from 1 to 127, denoting a
Q.931 error cause code.
busy specifies that the message will be
“USER BUSY” when modems are
unavailable.
not available specifies that the message
will be “CHANNEL NOT
AVAILABLE” when modems are
unavailable.
21 Router(config-if)#isdn
fast-rollover-delay
seconds
(Optional) Configure a fast rollover
delay.
22 Router(config-if)#isdn sending-complete (Optional) Configure the BRI interface
to include the Sending Complete
information element in the outgoing
call Setup message. Used in some
geographic locations, such as Hong
Kong and Taiwan, where the sending
complete information element is
required in the outgoing call setup
message.
Step Command Purpose

Verify
Modem over ISDN BRI for the Cisco 3640 Router 7
Verify To verify the ISDN BRI interface configuration, use the commands demonstrated below. The text
shown in bold displays the results of configuration steps such as those shown in the “Configuration
Tasks” section on page 4.
Step 1 The show running-config command in EXEC mode shows the current configuration
running on the terminal. The example below shows some of the command output that is
relevant to B RI configuration tasks.
Note The show startup-config shows the configuration stored in NVRAM or in a
location specified by the CONFIG_FILE environment variable.
Building configuration...
Current configuration:
!
version 12.0
no service udp-small-servers
service tcp-small-servers
!
hostname Router
!
enable secret 5 $1$c8xi$tObplXsIS.jDeo43yZgq50
enable password xxx
!
username xxxx password x 11x5xx07
no ip domain-lookup
ip host Labhost 10.17.12.1
ip host Labhost2 10.17.12.2
ip name-server 10.70.169.21
!
interface Ethernet0
Table 1 ISDN Switch Types
Country ISDN Switch Type Description
Australia basic-ts013 Australian TS013 switches
Europe basic-net3 ETSI ISDN switches (UK and others)
basic-nwnet3 Norwegian NET3 ISDN switches (phase 1,
no longer exist, basic-net3 used instead)
basic-1tr6 National German ISDN switches
basic-vn2 National French ISDN switches
basic-vn3 National French ISDN switches
Japan ntt Japanese NTT ISDN switches
New Zealand basic-nznet3 New Zealand NET3 switches (no longer
exist, basic-net3 used instead)
North America basic-5ess Custom 5ESS switch
basic-dms100 NT DMS-100 switch
basic-ni National ISDN switches

Configuration Tasks
8Cisco IOS Release 12.0(3)T
ip address 10.17.12.100 255.255.255.192
no ip mroute-cache
no ip route-cache
no mop enabled
...
interface BRI1/7
description [phone]
ip address 10.1.1.26 255.255.255.1
no ip directed-broadcast
encapsulation ppp
no ip route-cache
no ip mroute-cache
no keepalive
shutdown
dialer idle-timeout 180
dialer map ip 10.1.1.9 name MDial1 14085550715
dialer map ip 10.1.1.14 name MDial2 14085553775
dialer-group 1
isdn switch-type basic-5ess
isdn incoming-voice modem
modem-busy-cause busy
no fair-queue
no cdp enable
ppp authentication chap
ppp multilink
...
!
interface Group-Async1
ip unnumbered Loopback0
no ip directed-broadcast
ip tcp header-compression passive
async mode interactive
peer default ip address pool default
no fair-queue
group-range 65 70
hold-queue 10 in
!
router igrp 109
network 10.21.0.0
!
ip local pool local 10.21.50.85 10.21.50.89
ip local pool default 10.1.1.1 10.1.1.253
ip classless
ip route 0.0.0.0 0.0.0.0 10.21.48.1
!
!
map-class dialer VOICE
dialer voice-call
!
map-class dialer DATA
dialer-list 1 protocol ip list 101
tacacs-server host 10.69.2.74
tacacs-server host 10.92.15.197
snmp-server community isdn RW
snmp-server enable traps isdn call-information
snmp-server host 10.69.3.154 traps isdn

Example 1: BRI Interfaces
Modem over ISDN BRI for the Cisco 3640 Router 9
Step 2 The show interfaces bri number command displays information about the physical
attributes of the ISDN BRI B and D channels. number is the slot location of the BRI
module. Valid values are from 0 to 3.
BRI0:1 is down, line protocol is down
Hardware is BRI
MTU 1500 bytes, BW 64 Kbit, DLY 20000 usec, rely 255/255, load 1/255
Internet address is 10.1.1.3/27
Encapsulation PPP, loopback not set, keepalive not set
LCP Closed
Closed: IPCP
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Queueing strategy: fifo
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 7 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
Configuration Examples
The following examples show configuration of just the Modem over ISDN BRI feature using the
interface configuration commands for each interface, as well as a complete configuration example
showing global configuration, BRI interfaces, and modem configuration.
Example 1: BRI Interfaces
The example below shows how to configure each BRI interface on a Cisco 3640 router for the
Modem over ISDN BRI feature.
interface BRI0/0
no ip address
no ip directed-broadcast
encapsulation ppp
isdn switch-type basic-ni
isdn spid1 0444000101 9194440001
isdn spid2 0444001101 9194440011
isdn incoming-voice modem
no shut
!
interface BRI0/1
no ip address
no ip directed-broadcast
encapsulation ppp
isdn switch-type basic-ni
isdn spid1 0444000201 9194440002
isdn spid2 0444001201 9194440012
isdn incoming-voice modem
no shut
!

Configuration Examples
10 Cisco IOS Release 12.0(3)T
interface BRI0/2
no ip address
no ip directed-broadcast
encapsulation ppp
isdn switch-type basic-ni
isdn spid1 0444000301 9194440003
isdn spid2 0444001301 9194440013
isdn incoming-voice modem
no shut
!
interface BRI0/3
no ip address
no ip directed-broadcast
encapsulation ppp
isdn switch-type basic-ni
isdn spid1 0444000401 9194440004
isdn spid2 0444001401 9194440014
isdn incoming-voice modem
no shut
!
interface BRI0/4
no ip address
no ip directed-broadcast
encapsulation ppp
isdn switch-type basic-ni
isdn spid1 0444000501 9194440005
isdn spid2 0444001501 9194440015
isdn incoming-voice modem
no shut
!
interface BRI0/5
no ip address
no ip directed-broadcast
encapsulation ppp
isdn switch-type basic-ni
isdn spid1 0444000601 9194440006
isdn spid2 0444001601 9194440016
isdn incoming-voice modem
no shut
!
interface BRI0/6
no ip address
no ip directed-broadcast
encapsulation ppp
isdn switch-type basic-ni
isdn spid1 0444000701 9194440007
isdn spid2 0444001701 9194440017
isdn incoming-voice modem
no shut
!
interface BRI0/7
no ip address
no ip directed-broadcast
encapsulation ppp
isdn switch-type basic-ni
isdn spid1 0444000801 9194440008
isdn spid2 0444001801 9194440018
isdn incoming-voice modem
no shut
!