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The following sections are provided:
This document describes how to configure, verify, and troubleshoot a Cisco 3600 series router after the ATM OC-3 Network Module has been installed. The ATM OC-3 Network Module allows your router to concentrate data, voice, and video traffic onto an Asynchronous Transfer Mode (ATM) uplink. The following models are available:
| Network Module | Description |
|---|---|
NM-1A-OC3MM | Single port ATM OC-3 multinode network module. |
NM-1A-OC3SMI | Single port ATM OC-3 single-mode, intermediate reach network module. |
NM-1A-OC3SML | Single port ATM OC-3 single-mode, long reach network module. |
The ATM OC-3 Network Module is an ATM network module designed for Optical Carrier level 3 (OC3) high-bandwidth data and voice or data integration applications over Synchronous Optical Network (SONET) and Synchronous Digital Hierarchy (SDH) at speeds of 155.520 Mbps (STM-1). The ATM OC-3 network module can combine router packets with constant bit rate (CBR) data onto an ATM uplink. This network module provides the following features at the ATM Adaptation Layer (AAL) and ATM layers:
The Segmentation and Reassembly (SAR) converts packets to and from cells that are using the AAL5 adaptation layer. The SAR also provides comprehensive bit rate management providing UBR, VBR, CBR and full end-to-end ABR service.
The OC3 port provides three different fiber interfaces: multimode, single-mode intermediate reach, and single-mode long reach capabilities. The uplink port accepts transmission timing from the primary reference clock on the backplane or from the ATM network.
The ATM OC-3 network module can be configured with the following restrictions:
If you are still having trouble, enable ATM debug mode using the debug atm errors command.
These modular access routers support theATM OC-3:
ABR---Available Bit Rate service, provides a feedback path in VCs using RM cells to indicate buffer congestion and automatically decrease/increase data rate on a VC.
ATM ---Asynchronous Transfer Mode (NOT Automatic Teller Machine)
CBR---Constant Bit Rate interfaces usually run at T1 or E1 speed and are used mostly to connect PBXs or video equipment
OC3---optical carrier level 3, the optical interface designed with synchronous transport signal (STS-3) rate in SONET.
PVC---permanent virtual circuit made between two data terminal equipment (DTE) lines established by configuration.
SAR---Segmentation and Reassembly, a circuit device that converts packets into cells and visa-versa.
SVC---switched virtual circuit established across a network on as-need basis.
SONET---synchronous optical network
STM-1---Synchronous Transfer Mode level 1
UBR---Unspecified Bit Rate service category for ATM traffic. This is intended for non-real time burst applications which do not require a guarantee of traffic characteristics such as bandwidth, cell delay and cell delay
VBR---variationvariable bit rate
VC---Virtual Circuit
VCI---Virtual Channel Identifier
VPI---Virtual Path Identifier
rt-VBR---Real time Variable Bit Rate traffic service category for ATM traffic.
nrt-VBR---Non-real time Variable Bit Rate traffic service category for ATM traffic.
Figure 1 shows a sample network topology for the ATM OC-3 network module installed in a Cisco 3600 series router. When a Cisco 3600 series router is deployed in an ATM wide area network (WAN) with a ATM OC-3 network module installed, high speed connectivity will be supported for multiple types of traffic over ATM. For a sample configuration, see the ""Configuration Examples":
Perform the following tasks to configure the ATM OC-3:
The ATM OC-3 network module supports most of the standard ATM Cisco command line interface (CLI) configuration and troubleshooting commands. See Table 2 for specific supported ATM related CLI commands. Configuring your Cisco 3600 to fully support ATM network capabilities is beyond the scope of this short document.
| Step | Command | Purpose | ||
|---|---|---|---|---|
| Router# configure t | After installing your ATM OC-3 network module, enter the global configuration mode by typing the configure terminal command so you can configure ATM permenant virtual circuit (PVCs) or switched virtual circuit (SVCs) for your Cisco 3620 or 3640 router. | ||
| If you have not configured any routing for the Cisco 3600 Series Router, do it next. | |||
| Router(config)# interface atm slot/port | Specify the ATM controller that you want to configure. | ||
| Router(config-if)# no shutdown | Enter the no shutdown command to pass an enable command to the ATM interface, which then begins segmentation and reassembly (SAR) operations. This command also causes the ATM interface to configure itself based on the previous configuration commands sent. | ||
| Router(config-if)# ip address ip-addr mask | Enter an IP address that the ATM interface will use for routing. | ||
| Router(config-if)# pvc [vc-id] vpi/vci encap [ilmi|qsaal] | Specifiy the PVC with a VC identification number, a VPI, a VCI, and a type of encapsulation. All other choices are optional. VCI values 0 to 31 are reserved by ITU-T and ATM Forum. Entering this command places you in config-if-vc ATM vc configuration mode. | ||
| Router(config-if-atm-vc)# protocol ip ip-addr broadcast Router (config-if-atm-vc)# exit Router (config-if)# | Enter the protocol ip ip-addr [[no]broadcast] command (a good replacement for the "map-group/map-list" comination, and more appropriate for this interface. | ||
| Router(config-map-list)# ^Z | Close the interface dropping out of configuration mode. |
For a more detailed PVC configuration example, see "Configuration Examples".
To verify the correct PVC configuration:
Router# show interface atm 2/0
ATM2/0 is up, line protocol is up
Hardware is RS8234 ATMOC3
Internet address is 200.200.200.1/24
MTU 4470 bytes, sub MTU 4470, BW 155000 Kbit, DLY 80 usec,
reliability 20/255, txload 1/255, rxload 1/255
Encapsulation ATM, loopback not set
Keepalive not supported
Encapsulation(s):AAL5
1024 maximum active VCs, 1 current VCCs
VC idle disconnect time:300 seconds
Last input never, output 1d21h, 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 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
6 packets output, 2562 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 output buffer failures, 0 output buffers swapped out
---- cut ----
| LED | Color | Meaning |
|---|---|---|
EN (Enable) | Green | Module has passed its self-tests and is available to the router. |
RCLK | Green | Receive clock has been detected. |
FERF | Yellow | Far End Receive Failure. |
OOF | Yellow | Out Of Frame. |
AIS | Yellow | Alarm Indication Signal. |
Router# show interface atm3/0
ATM3/0 is up, line protocol is up
Hardware is RS8234 ATMOC3
Internet address is 1.12.100.1/24
MTU 4470 bytes, sub MTU 4470, BW 155000 Kbit, DLY 80 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ATM, loopback set
Keepalive not supported
Encapsulation(s): AAL5
1024 maximum active VCs, 1 current VCCs
VC idle disconnect time: 300 seconds
Last input 00:09:14, output 00:09:14, 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
30 second input rate 0 bits/sec, 0 packets/sec
30 second output rate 0 bits/sec, 0 packets/sec
1404 packets input, 44928 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
1404 packets output, 44928 bytes, 0 underruns
1 output errors, 0 collisions, 2 interface resets
0 output buffer failures, 0 output buffers swapped out
Router# show controller atm3/0 ---- cut ---- PM5346 info: Framer Chip Type PM5346 Framer Chip ID 0x30 Framer State RUNNING Layer Status NO ERRORS Loopback Mode NONE Clock Source LINE SONET Mode STS3C Line Coding B3ZS Line Type LONG MM ---- cut ---- TX cells 56 TX bytes 2968 Last output time 00:01:00 RX cells 271 RX bytes 14363
Router# show atm vc
VCD / Peak Avg/Min Burst
Interface Name VPI VCI Type Encaps SC Kbps Kbps Cells Sts
1/0 1 0 5 PVC SNAP UBR 155000 UP
1/0 8 0 30 PVC SNAP UBR 155000 UP
1/0 31 1 1 PVC SAAL UBR 155000 UP
1/0 Ron 1 55 PVC SNAP UBR 155000 UP
1/0 3 1 111 PVC SNAP UBR 155000 UP
1/0 9 2 3 PVC F4-OAM UBR 155000 UP
1/0 10 2 4 PVC F4-OAM UBR 155000 UP
1/0 4 5 55 PVC SNAP CBR 10000 UP
1/0 5 6 66 PVC SNAP CBR 20000 UP
1/0 7 7 77 PVC SNAP UBR 155000 UP
2/0 1 0 5 PVC SAAL UBR 155000 UP
2/0 2 0 16 PVC ILMI UBR 155000 UP
3/0 1 15 100 PVC SNAP UBR 155000 UP
Router# show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default
U - per-user static route, o - ODR, P - periodic downloaded static route
T - traffic engineered route
Gateway of last resort is 172.18.70.1 to network 0.0.0.0
1.0.0.0/24 is subnetted, 1 subnets
C 1.12.100.0 is directly connected, ATM3/0
172.18.0.0/24 is subnetted, 1 subnets
C 172.18.70.0 is directly connected, Ethernet0/0
C 192.22.1.0/24 is directly connected, ATM2/0.1
S* 0.0.0.0/0 [1/0] via 172.18.70.1
S 171.0.0.0/8 [1/0] via 172.18.70.1
S 172.0.0.0/8 [1/0] via 172.18.70.1
S 161.0.0.0/8 [1/0] via 172.18.70.1
Two examples are suggested for your ATM interface.
The following example configures an ATM interface with a permenant virtual circuit (PVC) connection.
Step 1 Enter global configuration mode using the configure terminal command:
Router# configure terminal Enter configuration commands, one per line. End with CNTL/Z.
Step 2 If you have not configured the router before or want to change the current configuration, configure the global parameters, passwords, network management, and routing protocols first. In this example, IP routing and Internetwork Packet Exchange (IPX) routing are enabled:
Router(config)# ip routing Router(config)# ipx routing
For more information about global configuration mode commands, enter a ? at the prompt.
Step 3 Select the ATM interface to configure by entering the interface command, followed by the interface type and the slot and port number:
Router(config)# interface atm 1/0 Router(config-if)#
The prompt changes again to show that you are in interface configuration mode.
Step 4 Enable the ATM interface by changing the shutdown state to up:
Router(config-if)# no shutdown Router(config-if)# exit
Step 5 Configure routing protocols on the interface. You enabled the interfaces as part of the global configuration in Step 2. In this example, IP and IPX are configured on the atm 1/0 interface you entered in step 3:
Router(config-if)# ip address 192.22.74.3 255.255.255.0 Router(config-if)# ipx network B005 Router(config-if)#
Step 6 Configure the entire path from source to destination for a PVC manually as well as any switches in the path. The command that creates a PVC has the format pvc vc-id vpi vci encap [peak-rate sustained-rate burst-size], as follows:
Router(config-if)# pvc 1 32 Router(config-if-atm-vc)#
Step 7 Assign the appropriate map list to the interface:
Router(config-if-atm-vc)# protocol ip 192.22.74.2 broadcast Router(config-if-atm-vc)#
Use the protocol command to map protocol addresses to the PVC. Doing this eliminates the need for map group lists for virtual circuits (VCs).
Step 8 To configure another interface, repeat Steps 3 through 7 of this procedure.
Step 9 When you finish configuring interfaces, exit configuration mode and return to the enable prompt by pressing Ctrl-Z. To see the current operating configuration, including any changes you just made, enter the show running-config command:
Router# show running-config Router#
Step 10 To see the configuration currently stored in non-volatile random access memory (NVRAM), enter the show startup-config command at the enable prompt:
Router# show startup-config Router#
Step 11 Changes to your configuration are evident when you compare the results of the show running-config and the show startup-config commands before you write your new configuration to NVRAM. To write your changes to NVRAM, making the changes permanent, enter the copy running-config startup-config command at the enable prompt:
Router# copy running-config startup-config Building configuration. . . [OK] Router#
To configures an ATM interface with a switched virtual circuit (SVC) connection:
Step 1 Enter global configuration mode using the configure terminal command:
Router# configure terminal Enter configuration commands, one per line. End with CNTL/Z.
Step 2 If you have not configured the router before or want to change the configuration, configure global parameters, passwords, network management, and routing protocols first. In this example, IP routing, and Internetwork Packet Exchange (IPX) routing are enabled:
Router(config)# ip routing Router(config)# ipx routing
For more information about global configuration mode commands, enter a question mark ? at the prompt.
Step 3 Select the ATM interface to configure by entering the interface command, followed by the interface type and the slot/port number:
Router(config)# interface atm 1/0 Router(config-if)#
The prompt changes again to show that you are in interface configuration mode.
Step 4 Enable the interface by changing the shutdown state to up:
Router(config-if)# no shutdown Router(config-if)# ^Z Router#
Step 5 Configure routing protocols on the interface. You enabled the interfaces as part of the global configuration in step 2. In this example, IP and IPX are configured on the atm 1/0 interface you entered in step 3:
Router(config-if)# ip address 192.22.74.3 255.255.255.0 Router(config-if)# ipx network B005 Router(config-if)#
Step 6 Configure the signalling PVC which the signalling software needs to dynamically set up SVCs with the switch. The signalling virtual channel uses VPI 0 and VCI 5:
Router(config-if)# pvc 1/5 qsaal Router(config-if-atm-vc)# exit Router#
Step 7 Configure an ILMI PVC.
Router(config-if)# pvc 1/16 ilmi Router(config-if-atm-vc)# exit Router(config-if)
This is required for ILMI administration.
Step 8 Configure the ATM network service access point, the end station ID (ESI) address:
Router(config-vc)# atm esi-address 345678901234.12 Router(config-vc)
Step 9 Map the protocol addresses to ATM NSAP addresses, as shown in the following example:
Router(config-if-atm-vc)# protocol ip 192.22.1.2 AB.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12 br Router(config-if-atm-vc)# protocol ip 192.22.1.3 CD.EFAB.01.234567.890A.BCDE.F012.3456.7890.1234.12 br Router(config-if-atm-vc)# exit Router(config-if)#
Step 10 Configure the entire path from source to destination for a SVC, manually as well as any switches in the path. The command that creates a SVC has the format svc [vc-id] nsap 47.0091.81.000000.0040.0B0A.2501.ABC1.3333.3333.05, as follows:
Router(config-if)# svc 1 32.0081.21.0000000.0030.0B0A.2501ABC1.2323.2323.02 Router(config-if-atm-vc)#
Step 11 To configure another interface, repeat Steps 3 through 10 of this procedure.
Step 12 When you finish configuring interfaces, exit configuration mode and return to the enable prompt by pressing Ctrl-Z. To see the current operating configuration, including any changes you just made, enter the show atm vc command:
Router# show atm vc
VCD / Peak Avg/Min Burst Interface Name VPI VCI Type Encaps SC Kbps Kbps Cells Sts 2/0 5 0 5 SVC SAAL UBR 155000 UP 2/0 6 0 16 SVC ILMI UBR 155000 UP 2/0.2 1 1 100 SVC SNAP UBR+ 50000 0 UP 2/0.3 2 1 101 SVC SNAP ABR 10000 0 UP 2/0.4 3 1 102 SVC SNAP CBR 16000 UP Router#
Step 13 To see the configuration currently stored in NVRAM, enter the show startup-config command at the enable prompt:
Step 14 Changes to your configuration are evident when you compare the results of the show running-config and the show startup-config commands before you write your new configuration to NVRAM. To write your changes to NVRAM, making the changes permanent, enter the copy running-config startup-config command at the enable prompt:
After you have finished configuring the new ATM interface, perform the following tests to verify that the new interface is operating correctly:
If an interface is down and you configured it as up, or if the displays indicate that the hardware is not functioning properly, make sure that the new interface is properly connected and configured. If you still have problems, refer to the next section, "Cisco Connection Online."
This section documents new and modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.0(3) Command References.
| ATM Commands | Support Provided | Description |
|---|---|---|
abr | Supported. | Enter Available Bit Rate (pcr)(mcr). |
abr rate | Supported. | Enter Available Bit Rate (pcr)(mcr) |
abr rate-factors | Not supported for this release. | Set abr rat-factors. |
atm max-vc | Not supported for this release. | Maximum value is 1024. |
atm aal aal3/4 | Not supported for this release. | Only aal5 is supported. |
atm address-registration | Supported. | Address Registration with ILMI. |
atm arp-server | Supported. | Configure IP ARP Server or set TTL values in ARP Table. |
atm classic-ip-extensions | Supported. | Specify the type of Classic IP extensions (to support simple redundant ARP server or none). |
atm clock | Supported. | ATM TX clock source (network or internal). |
atm esi-address | Supported. | 7-octet ATM ESI (End Station ID) used with ILMI. |
atm exception-queue | Not supported for this release. | Number of atm events, such as CRC errors, which can be queued. |
atm idle-timeout | Supported. | Set idle time before disconnecting an SVC. |
atm ilmi-keepalive | Supported. | Enable ILMI keepalive. |
atm multicast | Not supported for this release. | No support is provided for AAL3/4 and SMDS. |
atm mid-per-vc | Not supported for this release. | Message identifiers per VC. Used in AAL3/4 encapsulation. |
atm multipoint-interval | Supported. | Set minimum interval between multipoint party additions. |
atm multipoint-signalling | Supported. | Multipoint signalling. |
atm nsap-address | Supported. | 20-octet ATM NSAP address. |
atm pvc | Supported. | Create a PVC. Configure a PVC. aal34smds encapsulation, midlow, midhigh are not supported. |
atm rate-queue | Not supported for this release. | ATM Rate Queue is not supported as the hardware does not use rate queues for traffic shaping. |
atm rawq-size | Not supported for this release. | Raw queue is used for OAM and ILMI cells. |
atm rxbuff | Not supported for this release. | Configure number of reassembly buffers. |
atm sig-traffic-shaping | Not supportedfor this release. | Traffic shaping must match signaled traffic. |
smds-address | Not supported for this release. | E.164 ATM SMDS address. |
atm txbuff | Not supported for this release. | Configure number of segmentation buffers for AIP. |
atm vc-per-vp | not supported for this release | Configure size of VCI table. 16 VPIs and a max of 1024 connections are allowed. |
atm vp-filter | Not supported for this release. | Specify AIP's filter register value to designate which VPIs are used for AAL3/4. |
atm sonet | Supported. | Select STS-3C or STM-1 (for Oc3 uplink only). |
atm uni-version | Supported. | Used when ILMI is not enabled or unsuccessfully configured. |
atmsig close | Supported. | Disconnect the SVC associated with the given VCD number. If the VCD number is -1, then close all SVCs. |
broadcast | Supported. | Provide for a pseudo-broadcast. |
class | Supported. | ATM vc-class name to use on this VC. |
class-vc | Supported. | ATM vc-class name to use on this VC. |
debug atm | Supported. | Display debug output for ATM traffic. |
encapsulation | Supported. | Specify ATM Encapsulation for VC. |
inarp | Supported. | Send OAM cells on this PVC. |
idle-timeout | Supported. | Establish timeout after value is set. |
ilmi manage | Supported. | Enable/disable ILMI management. |
map-list | Supported. | Specify the map list to which the subsequent map-list configuration commands apply. |
map-group | Supported. | To associate an ATM interface with a map-list. |
oam-pvc | Supported. | Send oam cells on this pvc. |
oam-svc | Supported. | Display the SVC. |
oam retry | Supported. | Configure OAM retry parameter. |
protocol | Supported. | Map an upper layer protocol to this connection. |
pvc <name> <vpi/vci> | Supported. | To specify a PVC. |
show atm interface | Supported. | Displas interface-specific information. |
show atm traffic | Supported. | ATM packet/OAM statistics. |
show atm vc | Supported. | Display all VC related statistics. |
show atm map | Supported. | Display data about all configured ATM static maps. |
show controller atm | Supported. | Displays all controller related information. |
show atm pvc | Supported. | Show ATM PVC information. |
show atm svc | Supported. | Show ATM SVC information. |
svc <name> nsap | Supported. | To specify a SVC. |
ubr | Supported. | Enter unspecified peak cell rate (pcr) in Kbps. |
ubr+ | Supported. | Enter peak cell rate(pcr) minimum cell rate(mcr) in Kbps. |
vbr-nrt | Supported. | Enter variable bit rate (pcr) (scr) (bcs). |
vc-class | Supported. | Display the VC class. |
To manage bandwidth for service categories other than constant bit rate (CBR), enable the atm overscribe command on a per-ATM-interface basis. To disable bandwidth management, use the no form of the command.
atm oversubscribeThere are no optional keywords for this command.
The default is to allow as much bandwidth as possible with no upper limits. The no form of the atm overscribe command enables bandwidth management on any ATM interface you specify.
Global configuration
This command first appeared in Cisco IOS Release 12.0(3)T for the Cisco 3600 series routers.
When you type the enabling command (the no version), a check determines if the ATM link is already oversubscribed. If so, the command is rejected. Otherwise, the total bandwidth available on the link is recorded and all future connection setup requests are monitored to ensure that the link is not oversubscribed.
The bandwidth allocated for each service category is displayed in the output of the show atm interface atm command.
The ATM bandwidth manager keeps track of bandwidth used by VCs on a per-interface basis. Because many services require guaranteed bandwidth (for VBR-RT, ABR, CBR, for instance), bandwidth management is required. The purpose of the bandwidth manager is to reserve resources for connections that require guaranteed services. Bandwidth management for CBR is turned on automatically for all interfaces supporting CBR. Bandwidth management for other service categories must be turned on by the user. All service categories outside CBR is monitored only if specifically requested.
In all cases, bandwidth check for a PVC is done when the PVC is configured. Bandwidth check for a SVC is done when a signaling call is placed or received.
When you specify the atm pvp command, the system checks if the specified bandwidth is available on the interface. If the bnadwidth available is greater than or equal to the peak rate specified for the PVP, the command is accepted, otherwise the command is rejected.
Within the VC mode the steps taken to check for bandwidth available are to ascertain if the bandwidth is already used by the VC to fulfill the request. If the VC being configured is a PVC and belongs to a PVP, the bandwidth available on the PVP is used for the check; otherwise the bandwidth available on the interface is used for the check.
When configuring services within a VC class, the steps taken are to check if the new bandwidth requirement can be fulfilled for all VCs using the class (on a per-interface basis), by comparing with the bandwidth available on the corresponding interface.
Bandwidth checking for an SVC occurrs before a SETUP message is sent for an outbound call. If the bandwidth check fails, the SETUP message is not sent. If the bandwidth check passes, the traffic class from which the service category is inherited, is updated with the requirements for the new SVC.
When a SVC setup is requested for remotely initiated calls, a bandwidth check occurs as soon as the SETUP message is received. This bandwidth check has two components:
1. Match the bandwidth requested by the remote end with the bandwidth configured locally
2. Check if bandwidth configured locally can be satisfied currently
If the bandwidth check fails, a RELEASE message is sent out and the call is rejected. If the bandwidth check passes, resources are reserved for the VC and the call is accepted.
The following example displays the available bandwidth after you enter VC mode. Notice that the bandwidth is specified in Kbits per second.
Router# show atm interface atm 2/0
Interface ATM2/0: AAL enabled: AAL5 , Maximum VCs:1024, Current VCCs:5 Maximum Transmit Channels:64 Max. Datagram Size:4496 PLIM Type:SONET - 155Mbps, TX clocking:LINE Cell-payload scrambling:OFF sts-stream scrambling:ON 877 input, 120843834 output, 0 IN fast, 20 OUT fast ABR parameters, rif:16 rdf:16, 0 out drop Bandwidth distribution :CBR :16000 Avail bw = 139000 Config. is ACTIVE Router#
Notice that the bandwidth is specified as (139000) Kbits/second.
For additional software configuration information, see the following publications:
For additional configuration information, click on the Cisco Release 12.0 Wide Area Networking Configuration and Command References:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/12cgcr/wan_r/index.htm
Posted: Mon Mar 1 15:12:29 PST 1999
Copyright 1989-1999©Cisco Systems Inc.