Extreme Networks Network Router WM 4T1i User Manual

WM-4T1i Module  
Installation and User  
Guide  
Extreme Networks, Inc.  
3585 Monroe Street  
Santa Clara, California 95051  
(888) 257-3000  
Published: June 2001  
Part number: 100095-00 Rev. 01  
 
Contents  
Preface  
Conventions  
1
1-2  
Installing the WM-4T1i Module  
Ports and Connectors  
1-3  
2
Alarms  
2-3  
2-3  
2-4  
2-4  
2-4  
Clock Source  
Facility Data Link  
Framing  
Inband Loopback Detection  
Linecoding  
WM-4T1i Installation and User Guide  
iii  
 
Near-end Loopback Modes  
Enabling Loopback Mode  
Disabling Loopback Mode  
2-7  
2-10  
2-10  
3
3-3  
PPP Link Username  
Monitoring PPP/ MLPPP Links  
3-6  
PPP/ MLPPP Configuration Examples  
3-6  
3-7  
Configuring a Routed PPP/ MLPPP Link Example  
Index  
Index of Commands  
iv  
WM-4T1i Installation and User Guide  
 
Preface  
This Preface provides an overview of this guide, describes guide conventions, and lists  
other publications that may be useful.  
Introduction  
This guide provides the required information to install the WM-4T1i module in an  
Alpine 3800 series switch from Extreme Networks and perform the initial module  
configuration tasks.  
This guide is intended for use by network administrators who are responsible for  
installing and setting up network equipment. It assumes a basic working knowledge of:  
Local area networks (LANs).  
Ethernet concepts.  
Ethernet switching and bridging concepts.  
Routing concepts.  
Internet Protocol (IP) concepts.  
Routing Information Protocol (RIP) and Open Shortest Path First (OSPF).  
Simple Network Management Protocol (SNMP).  
If the information in the release notes shipped with your module differs from the  
information in this guide, follow the release notes.  
WM-4T1i Module Installation and User Guide  
 
v
   
Conventions  
Table 1 and Table 2 list conventions that are used throughout this guide.  
Table 1: Notice Icons  
Icon  
Notice Type  
Alerts you to...  
Note  
Important features or instructions.  
Caution  
Warning  
Risk of personal injury, system damage, or loss of data.  
Risk of severe personal injury.  
Table 2: Text Conventions  
Convention  
Description  
Screen displays  
This typeface indicates command syntax, or represents information  
as it appears on the screen.  
Screen displays  
bold  
This typeface indicates how you would type a particular command.  
The words “enter”  
and “type”  
When you see the word “enter” in this guide, you must type  
something, and then press the Return or Enter key. Do not press the  
Return or Enter key when an instruction simply says “type.”  
[Key] names  
Key names are written with brackets, such as [Return] or [Esc].  
If you must press two or more keys simultaneously, the key names  
are linked with a plus sign (+). Example:  
Press [Ctrl]+[Alt]+[Del].  
Words in italicized type Italics emphasize a point or denote new terms at the place where  
they are defined in the text.  
vi  
WM-4T1i Module Installation and User Guide  
 
         
Related Publications  
Related Publications  
The publications related to this one are:  
ExtremeWarerelease notes  
ExtremeWare Software User Guide  
Alpine 3800 Series Switch Hardware Installation Guide  
Alpine Module Installation Note  
Documentation for Extreme Networks products is available on the World Wide Web at  
the following location:  
http:/ / www.extremenetworks.com/  
WM-4T1i Module Installation and User Guide  
 
vii  
 
viii  
WM-4T1i Module Installation and User Guide  
 
Installing the WM-4T1i Module  
1
Installing the WM-4T1i Module on page 1-2  
Ports and Connectors on page 1-3  
WM-4T1i Module LEDs on page 1-3  
Installing the WM-4T1i Module Software on page 1-5  
Overview  
The Extreme Networks WM-4T1i module is an four-port T1 module that can be  
configured to use Multilink PPP to aggregate Ethernet traffic across multiple T1  
physical links. The module has two 10/ 100 Mbps Ethernet ports.  
The WM-4T1i module also has six internal loopback ports. The Alpine 3800 switch  
modules have hardware queues associated with the output of each port for QoS (rate  
shaping and priority queueing). To implement ingress QoS, you needed to use the  
hardware queues associated with a second port as a loopback port for ingress QoS  
WM-4T1i Module Installation and User Guide  
 
1-1  
     
Installing the WM-4T1i Module  
Installing the WM-4T1i Module  
All Alpine 3800 series switch module cards (SMMi modules and I/ O modules) are  
hot-swappable. You do not need to power off the system to remove or insert a module  
card.  
Caution: Service to Alpine modules should be performed by trained service  
personnel only. Before installing or removing any components of the system, or  
before carrying out any maintenance procedures, read the safety information  
provided in Appendix A of the Alpine Hardware Installation Guide.  
Warning: You must install blank panels in empty slots to ensure adequate system  
cooling.  
To remove and replace a module card, follow these steps:  
1
Prior to removing/ installing a module card into the Alpine 3804 or Alpine 3808  
chassis, put on the ESD wrist strap that is provided with the chassis, and connect the  
metal end to the ground receptacle located on the top-right corner of the Alpine  
front panel.  
2
3
Loosen the module card by unscrewing the screws using a #2 Phillips-head  
screwdriver.  
Rotate the ejector/ injector handles to disengage the module card from the backplane.  
Note: Blank panels do not have ejector/injector handles, because they do not  
engage the backplane. They are secured entirely by the retaining screws. In  
addition, the retaining screws are not captive.  
4
5
Slide the module card out of the chassis.  
Slide the new module card into the appropriate slot of the chassis (SMMi modules  
into the orange slot, I/ O modules into Slots 1 through 4 on the Alpine 3804, or Slots  
1 through 8 on the Alpine 3808), until it is fully seated in the backplane.  
Caution: Ensure that the sheet metal of the module, and not the PCB board,  
engages the card cage runners.  
As the module begins to seat in the chassis, the ejector/ injector handles will begin to  
close.  
6
To secure the module in the chassis, close the ejector/ injector handles by pushing  
them toward the center of the module card, and tighten the screws using a #2  
Phillips-head screwdriver.  
1-2  
WM-4T1i Module Installation and User Guide  
 
 
Ports and Connectors  
Note: Tighten the screws before inserting additional modules. If you insert  
additional modules before tightening the screws, you might unseat modules  
that you have not secured.  
Caution: You can only install I/O modules in the slots labeled Slot 1 through  
Slot 4 on the Alpine 3804, or Slot 1 through Slot 8 on the Alpine 3808. Forceful  
insertion can damage the I/O module and the connector pins on the backplane.  
Ports and Connectors  
The WM-4T1i module is show in Figure 1-1.  
Module status  
LEDs  
T1 ports  
10/100 Mbps ports  
38_WM4T1i  
Figure 1-1: WM-4T1i Module  
The WM-4T1i module has four T1 ports and two 10/ 100 Ethernet ports. The WM-4T1i  
also has six internal loopback ports. Internal loopback ports allow you to configure  
bi-directional rate-limiting without tying up any of the external ports for ingress rate  
shaping. Internal loopback ports are marked with the notation iLwhen displayed on  
the command line or with ExtremeWare Vista Web access.  
WM-4T1i Module LEDs  
The WM-4T1i module LEDs are shown in Figure 1-1.  
WM-4T1i Module Installation and User Guide  
 
1-3  
     
Installing the WM-4T1i Module  
Figure 1-2: WM-4T1i LEDs  
Table 1-1 describes the LED behavior on the WM-4T1i module.  
Table 1-1: WM-4T1i Module LEDs  
LED  
Color  
Indicates  
Status  
Off  
No power  
Amber  
Module seated in chassis  
Module powered up  
Green  
Diag  
Green (blinking)  
Off  
Power-on Self Test (POST) is running  
Normal operation  
T1 port (1-4) Amber  
Near-end fault detected (for example, no cable)  
Far-end fault detected  
Rapidly blinking  
amber  
Slowly blinking  
amber  
Physical link present, but no higher-layer link (port  
misconfigured or disabled)  
Green  
Physical link present, higher-layer link established,  
no traffic  
Alternating green Physical link present, higher-layer link established,  
and amber  
Green (blinking)  
Off  
traffic present  
Loopback testing mode  
No link present  
10/100 port  
(5,6)  
Green  
Link present  
Alternating green Traffic present  
and amber  
1-4  
WM-4T1i Module Installation and User Guide  
 
   
Installing the WM-4T1i Module Software  
The slowly blinking LEDs cycle once per second. The rapidly blinking LEDs cycle twice  
a second.  
Installing the WM-4T1i Module Software  
Once the WM-4T1i module is installed in the chassis, you must download an image file  
to the module.  
The image file contains the executable code that runs on the module. As new versions  
of the image are released, you should upgrade the software running on your module.  
The image is downloaded from either a Trivial File Transfer Protocol (TFTP) server on  
the network or from a PC connected to the serial port using the XMODEM protocol.  
Downloading a new image involves the following steps:  
Load the new image onto a TFTP server on your network (if you will be using  
TFTP).  
Load a new image onto a PC (if you will be using XMODEM).  
Download the new image to the module using the command  
download image slot <slot> [<ipaddress> | <hostname>] <filename>  
{primary | secondary}  
where the following is true:  
slotIs the slot in which the WM-4T1i module is installed.  
ipaddressIs the IP address of the TFTP server.  
hostnameIs the hostname of the TFTP server. (You must enable DNS to use this  
option. See the ExtremeWare Software User Guide for more information.)  
filenameIs the filename of the new image.  
primaryIndicates the primary image.  
secondaryIndicates the secondary image.  
The module can store up to two images; a primary and a secondary. When you  
download a new image, you must select into which image space (primary or secondary)  
the new image should be placed. If not indicated, the primary image space is used.  
You can select which image the switch will load on the next reboot by using the  
following command:  
WM-4T1i Module Installation and User Guide  
 
1-5  
 
Installing the WM-4T1i Module  
use image [primary | secondary]  
1-6  
WM-4T1i Module Installation and User Guide  
 
Configuring the T1 Physical Link  
2
This chapter covers the following topics:  
Configuring T1 Physical link on page 2-1  
Monitoring T1 Physical Link on page 2-6  
Overview  
T1 is a mature technology originally developed for voice telephone transmission. It was  
used to aggregate a number of voice lines into a single connection to the telephone  
network. Today T1 is also widely used to transmit digital data using widely available  
equipment and established wiring commonly available in diverse locations.  
Configuring T1 Physical link  
There are a number of parameters that can be configured for a T1 link. If you have  
control of both sides of the link, then the default configuration is probably the best  
choice. If you must connect to a line controlled by another organization, you will need  
to configure the line to correspond with the settings at the other end. You can specify  
the following parameters:  
Alarms  
Cable length  
WM-4T1i Module Installation and User Guide  
 
2-1  
         
Configuring the T1 Physical Link  
Framing  
Inband Loopback Detection  
Linecoding  
Yellow Alarms  
Alarms  
The T1 standard, ANSI T1.403, Bellcore TR-54016 and others, defines red, yellow, and  
blue alarms.  
A red alarm occurs when the T1 signal is lost or an out of frame error occurs. An out of  
frame error can be caused when the framing type configured for the local interface does  
not match the framing type of the incoming T1 signal or when the incoming signal does  
not contain a T1 framing pattern.  
A yellow alarm is also called a Remote Alarm Indication (RAI). When the remote end of  
a link does not receive a signal, it will transmit a yellow alarm signal back to the local  
end.  
A blue alarm is also called an Alarm Indication Signal (AIS). A blue alarm indicates that  
a device somewhere upstream has experienced a loss of signal.  
The default value is on. To configure whether alarms are generated and detected, use  
the following command:  
config ports <portlist> t1 alarms [on | off]  
Yellow alarms can be configured when T1 alarms are enabled. See Yellow Alarmson  
page 2-5 for more details on the following command:  
config ports <portlist> t1 yellow [detection | generation | both | off]  
Cable length  
Longer cable lengths cause greater loss for the T1 signal, so the transmitter hardware  
must transmit at a higher level to transmit data successfully. However, too high a signal  
level can cause crosstalk from one cable to another. The config ports t1  
2-2  
WM-4T1i Module Installation and User Guide  
 
       
Configuring T1 Physical link  
cablelengthcommand allows you to control the transmitter signal level for your  
conditions. Typically, your service provider will suggest the correct level.  
For short haul connections (less then 700 feet) the typical equipment uses less sensitive  
receivers. The transmitter level is usually set by selecting a cable length in feet, from the  
following values: 133, 266, 399, 533 or 655. Choose the next higher value if your cable  
length does not match one of the values. For example, choose 133 for a 50 foot cable  
and 533 for a 450 foot cable. The default value is 133, which corresponds to cables in the  
range of 0-133 feet.  
For longer distances (up to 6000 feet) the typical equipment uses more sensitive  
receivers, and crosstalk is more likely to occur. Under these conditions, the transmitter  
level is set by selecting a transmitter attenuation level in dB from the following values:  
-22.5, -15, -7.5, or 0.  
From lowest to highest transmitter level, use the following values for the config port  
t1 cablelengthcommand: -22.5 db, -15 db, -7.5 db, 0 db, 133 feet, 266 feet, 399 feet,  
533 feet, and 655 feet.  
To configure the cable length, use one of the following commands:  
config ports <portlist> t1 cablelength [0 | -7.5 | -15 | -22.5] db  
config ports <portlist> t1 cablelength [133 | 266 | 399 | 533 | 655]  
feet  
CLOCK SOURCE  
A clock is used to synchronize data transmission on the line. Generally, one end of the  
T1 link provides the master clock, and the other end of the link recovers the clock from  
the signal on the line. By default the clock source is derived from the line. If needed, an  
internal clock is available. To configure the clock source, use the following command:  
config ports <portlist> t1 clocksource [internal | line]  
Note: If the clock source is configured as “line”, but the clock cannot be  
recovered from the signal on the line, the hardware will use the internal clock  
instead.  
Facility Data Link  
Facility data link (FDL) uses twelve bits in the ESF frame to signal information about  
line and connection status. Since FDL is only meaningful for ESF framing, FDL settings  
WM-4T1i Module Installation and User Guide  
 
2-3  
     
Configuring the T1 Physical Link  
are ignored when a port is configured for SF framing. See Framingfor information on  
configuring framing.  
The two standards supported for FDL are ATT, described by the ATT 54016  
specification, and ANSI, described by the T1.403 standard. The default value is off. To  
configure FDL, use the following command:  
config ports <portlist> t1 fdl [off | att | ansi]  
Framing  
Framing is used to synchronize data transmission on the T1 line. Framing allows the  
hardware to determine when each packet starts and ends. The two choices for framing  
are Super Frame (SF), also known as D4, and Extended Super Frame (ESF). The ESF  
scheme is a newer standard and is enabled by default. To choose the framing scheme,  
use the following command:  
config ports <portlist> t1 framing [esf | sf]  
If you choose to use SF framing, you should disable yellow alarm detection for the T1  
line. SF framing may generate false yellow alarms. See Yellow Alarmson page 2-5 for  
more details.  
When inband loopback detection is enabled, a specific sequence of data in the signal  
payload from the remote end of the T1 link will cause the local end to enter network  
line loopback mode and send any received signal back to the remote end. Inband  
loopback detection is only possible if the FDL standard is configured as ATT. See  
Facility Data Linkon page 2-3 for more details. By default, inband loopback detection  
is off. See Loopbackon page 2-6 for more information about loopback modes. To  
configure inband loopback detection, use the following command:  
config ports <portlist> t1 lbdetect [off | inband]  
Linecoding  
Linecoding is the convention used to encode signals for transmission over the T1 line.  
You can choose from two linecoding standards, bipolar eight zero suppression (B8ZS) or  
alternate mark inversion (AMI). The default value is B8ZS. To configure linecoding, use  
the following command:  
config ports <portlist> t1 linecoding [b8zs | ami]  
2-4  
WM-4T1i Module Installation and User Guide  
 
                     
Configuring T1 Physical link  
Yellow Alarms  
A yellow alarm occurs on a device when its signal is not received at the remote end. It  
is also called a Remote Alarm Indication (RAI). You can disable detection and  
generation of yellow alarms for a T1 port. When SF framing is used, yellow alarm  
detection and generation should be set to off, because detection of yellow alarms is not  
reliable when data traffic is transmitted with SF framing (data traffic often contains bit  
combinations that do not occur for encoded voice traffic). The default value for yellow  
alarm generation and detection is both. To configure yellow alarms, use the following  
config ports <portlist> t1 yellow [detection | generation | both | off]  
T1 Port Configuration Commands  
Table 2-1 describes the commands used to configure a T1 port.  
Table 2-1: T1 Port Configuration Commands  
Command  
Description  
config ports <portlist> t1 alarms [on | off]  
Enables and disables alarms. The default  
setting is on.  
config ports <portlist> t1 cablelength [  
[133 | 266 | 399 | 533 | 655] feet  
| [0 | -7.5 | -15 | -22.5] dB]  
Specifies the cablelength attached to the T1  
port. The default is 0 dB.  
config ports <portlist> t1 clock source [internal Specifies the clock source used for  
| line]  
transmission. The default setting is line.  
config ports <portlist> t1 fdl [off | att | ansi]  
Specifies the facilities data link (FDL) format for  
the port. You cannot use FDL with SF framing.  
config ports <portlist> t1 framing [esf | sf]  
Specifies the framing type. The default setting  
is esf, Extended Super Frame (ESF). If sf is  
chosen, Super Frame (SF), set yellow alarm  
detection to off, since a yellow alarm can be  
incorrectly detected with SF framing.  
config ports <portlist> t1 lbdetect [off | inband] Enables and disables the port to respond to  
loopback requests from the remote end. The  
default setting is off.  
config ports <portlist> t1 linecode [b8zs | ami] Sets the linecoding. The default setting is b8zs.  
config ports <portlist> t1 yellow [detection |  
generation | both | off]  
Enable and disable yellow alarm detection and  
generation.  
WM-4T1i Module Installation and User Guide  
 
2-5  
                       
Configuring the T1 Physical Link  
Monitoring T1 Physical Link  
T1 devices have a built-in facility designed for troubleshooting the physical link, called  
loopback. The T1 link can also be monitored using show commands to display the  
current configuration of the link, any alarms on the link, link statistics, and link errors.  
Loopback  
The T1 device can be set up to loopback, that is, return a transmitted signal back to the  
sender so it can be compared with the original. There are several different types of  
loopback available to test different parts of the device and the line, specified in the T1  
standards.  
Local T1 Port  
Remote T1 Port  
Data out  
Data in  
Data in  
Data out  
Framer  
Framer  
Data with framing  
XM_010  
Figure 2-1: Normal operation of T1 link  
During normal operation of a T1 link, as the local data stream enters the framer, the  
appropriate framing bits are inserted into the data, and the framed signal is transmitted  
to the remote end. At the remote end, the process is reversed as the framing bits are  
discarded and the data stream is passed to the remote system.  
Loopback can be enabled on the near-end or the far-end of the link. The near-end  
loopback modes are controlled directly by the hardware on the near-end. Far-end  
loopback modes require the cooperation of the far-end hardware. A message is sent to  
the far-end to cause it to enter a far-end loopback mode. When loopback is enabled on a  
T1 port, the green port LED will blink.  
2-6  
WM-4T1i Module Installation and User Guide  
 
   
Monitoring T1 Physical Link  
Near-end Loopback Modes  
The near-end of the link can be enabled for the following three loopback modes:  
Local  
Network Line  
Network Payload  
The local loopback mode reflects the data stream internally to the near-end. The  
network line loopback mode reflects the signal to the far-end. The network payload  
mode reflects the data carried in the signal and regenerates framing information back to  
the far-end.  
Local T1 Port  
Remote T1 Port  
Data out  
Data in  
Data in  
Data out  
Framer  
Framer  
XM_011  
Figure 2-2: Local loopback mode  
Local Loopback Mode. When the local port is enabled for local loopback, the local  
data stream goes into the framer and the framing bits are inserted into the data, but the  
data is not transmitted to the remote end. Instead, it is sent back through the local  
framer, the framing bits are discarded, and the original data is returned. This mode tests  
the local end.  
WM-4T1i Module Installation and User Guide  
 
2-7  
 
Configuring the T1 Physical Link  
Local T1 Port  
Remote T1 Port  
Data out  
Data in  
Data in  
Data out  
Framer  
Framer  
XM_012  
Figure 2-3: Network line loopback mode  
Network Line Loopback Mode. When the local port is enabled for network line  
loopback mode, the received signal is sent back to the remote end without reframing  
the data. This mode primarily tests the integrity of the line from the remote side.  
Local T1 Port  
Remote T1 Port  
Data out  
Data in  
Data in  
Data out  
Framer  
Framer  
XM_013  
Figure 2-4: Network payload loopback mode  
Network Payload Loopback Mode. When the local port is enabled for network  
payload mode, the framer removes the framing bits from the received signal and  
recovers the transmitted data. This same data is then reframed and transmitted back to  
the remote end. This mode tests the line and the local circuitry from the remote side.  
Far-End Loopback Modes  
The far-end of the link can be enabled for the following two loopback modes:  
Remote Line  
Remote Payload  
2-8  
WM-4T1i Module Installation and User Guide  
 
 
Monitoring T1 Physical Link  
The remote line mode reflects the received signal back to the near-end. The remote  
payload mode reflects the data and regenerates the framing information back to the  
near-end.  
Local T1 Port  
Remote T1 Port  
Data out  
Data in  
Data in  
Data out  
Framer  
Framer  
XM_014  
Figure 2-5: Remote line loopback mode  
Remote Line Loopback Mode. When the local port is enabled for remote line  
loopback mode, it sends a request to the remote end to enter the equivalent of network  
line loopback mode. The signal transmitted to the remote end will be retransmitted as  
received back to the local end.  
Note: If the line is configured to use the ATT FDL standard, the remote end must  
be configured to detect inband loopback requests for the remote end to enter  
remote line loopback mode.  
Local T1 Port  
Remote T1 Port  
Data out  
Data in  
Data in  
Data out  
Framer  
Framer  
XM_015  
Figure 2-6: Remote payload loopback mode  
Remote Payload Loopback Mode. When the local port is enabled for remote payload  
loopback mode, it sends a request to the remote end to enter the equivalent of network  
payload loopback mode. When the remote end enters loopback mode, the framer at the  
WM-4T1i Module Installation and User Guide  
 
2-9  
Configuring the T1 Physical Link  
remote end removes the framing bits from the received signal and recovers the  
transmitted data. This same data is then reframed and transmitted back to the local end.  
Enabling Loopback Mode  
To enable a loopback mode, use one of the following commands:  
enable ports <portlist> t1 loopback local  
enable ports <portlist> t1 loopback network [line | payload]  
enable ports <portlist> t1 loopback remote [line | payload]  
Disabling Loopback Mode  
Use the following command to return the near and remote side of a T1 loopback mode  
to normal mode:  
disable ports <portlist> t1 loopback  
You can also use the following command to return the remote port to normal function  
from loopback mode:  
enable ports <portlist> t1 loopback remote loopdown  
T1 Port Monitoring Commands  
Table 2-2 describes the commands used to monitor a T1 port.  
Table 2-2: T1 Port Monitoring Commands  
Command  
Description  
disable ports <portlist> t1 loopback  
Disable the current loopback mode and return  
to normal function.  
enable ports <portlist> t1 loopback [local  
| network [line | payload] | remote [line  
| payload | loopdown]]  
Enable the port to locally loopback, to cause  
the remote link to loopback, and to stop the  
loopback.  
show ports {<portlist>} {t1} stats  
show ports {<portlist>} t1 alarms  
show ports {<portlist>} t1 configuration  
Displays real-time port statistics.  
Displays real-time port alarms.  
Displays the port configuration and status.  
2-10  
WM-4T1i Module Installation and User Guide  
 
                   
Monitoring T1 Physical Link  
Table 2-2: T1 Port Monitoring Commands (continued)  
Command  
Description  
show ports {<portlist>} t1 errors [near-end |  
far-end] [totals | intervals | current]  
Displays current and past errors.  
show ports {<portlist>} t1 info  
Displays the port configuration and status.  
WM-4T1i Module Installation and User Guide  
 
2-11  
   
Configuring the T1 Physical Link  
2-12  
WM-4T1i Module Installation and User Guide  
 
Configuring PPP and MLPPP  
3
Multilink PPP and Multilink Groups on page 3-2  
Configuring a PPP/ MLPPP Link on page 3-3  
Monitoring PPP/ MLPPP Links on page 3-6  
PPP/ MLPPP Configuration Examples on page 3-6  
Overview  
Point-to-Point Protocol (PPP) is used across the entire range of communication speeds  
and devices found on the internet. Typically, PPP uses Layer 3 to connect two broadcast  
networks, say two ethernet LANs, into a single WAN by transporting IP packets over a  
link. PPP can also use Layer 2 to bridge packets from one VLAN to another.  
Multilink PPP (MLPPP) is a protocol for combining a number of PPP links into one  
bundle that transports traffic over the links in the bundle. A multilink group is just a  
bundle of individual PPP links that are configured to work together as a single link.  
With a multilink group configured, it is easy to add or remove additional PPP links to  
provide bandwidth as needed. The multilink group balances traffic among the  
individual PPP links and properly sequences packets across the multilink group.  
Typically, you would add a multilink group to a VLAN, configure the multilink group  
by adding T1 ports and configuring PPP/ MLPPP parameters, and finally, enable the  
multilink group.  
WM-4T1i Module Installation and User Guide  
 
3-1  
             
Configuring PPP and MLPPP  
Multilink PPP and Multilink Groups  
Each multilink PPP group is given a name, up to 16 characters in length. All named  
components of the switch configuration must have unique names, so multilink groups  
and VLANs cannot have identical names. See the ExtremeWare Software User Guide for  
more information on allowable names for named components. Components are named  
using the createcommand. Once a component is named, you do not need to use the  
keyword for the component (see the shortcut below).  
Create the multilink group using the following command:  
create multilink <groupname>  
Once the multilink group is created, assign ports to it by using the following command:  
config multilink <groupname> add ports <portlist>  
or you can use the following shortcut:  
config <groupname> add ports <portlist>  
If the first port added to a multilink group is already configured for PPP, the multilink  
group will inherit the configuration of the first port. Any other ports added to the link  
will be configured to match the multilink configuration. The next section lists the  
configuration commands for multilink groups and single PPP links.  
Once the multilink group has been configured, it is added to a VLAN so that it can pass  
traffic from the VLAN across the link. To add a multilink group to a VLAN, use the  
following command:  
config vlan <vlan> add multilink <groupname>  
Typically the last step in configuring a multilink group is to use the following command  
to enable it:  
enable multilink <groupname>  
Any changes to an enabled multilink group will not take effect until the the multilink  
group is restarted. To restart a multilkink group, use the following command:  
restart multilink <groupname>  
3-2  
WM-4T1i Module Installation and User Guide  
 
     
Configuring a PPP/MLPPP Link  
Configuring a PPP/MLPPP Link  
All of the PPP configuration commands can be used to configure a single port or to  
configure a multilink group, so the following sections for PPP links also apply to  
MLPPP links. To configure a PPP/ MLPPP link you will need to choose the  
authentication and encapsulation for the link.  
If you change the configuration of an enabled PPP or MLPPP link, the changes will not  
take effect until the link is restarted. To restart a PPP link, use the following command:  
restart ports <portlist>  
To restart an MLPPP link, use the following command:  
restart multilink <groupname>  
Authentication  
By default, no authentication is configured on PPP links since the WM-4T1i module will  
typically be used with leased lineswhere both sides of the link are controlled and  
authentification is not required. If authentication is needed, the WM-4T1i module  
supports using PAP or CHAP. PPP authentication protocol (PAP) authenticates a user as  
the connection is established by sending a username and password. Challenge  
Handshake Authentication Protocol (CHAP) authenticates a user by sending a challenge  
across the link. The remote end calculates a response based on the user password and  
sends the response back across the link. CHAP is a more secure authentication protocol  
than PAP. The link can also be configured to attempt to use CHAP first, followed by  
PAP, if CHAP fails.  
To configure authentication on a PPP link, use the following command:  
config ppp authentication [off | chap | pap | chap-pap] [ports  
<portlist> | multilink <groupname>]  
PPP Link Username  
When the local end of a link initiates a PPP connection, the local end must send the  
appropriate authentication information. For PAP it sends the username and password,  
for CHAP it sends the username and must respond correctly to the challenge, and for  
no authentication it sends nothing. To configure the username and password used to  
initiate the link, use the following command:  
WM-4T1i Module Installation and User Guide  
 
3-3  
                 
Configuring PPP and MLPPP  
config ppp user <username> {encrypted} <password> [ports <portlist> |  
multilink <groupname>]  
The encrypted keyword is used to hide the password when the switch configuration is  
displayed, it does not control whether the password is encrypted across the link during  
authentication.  
PPP User Accounts  
When the remote end initiates the link, the local end must verify the authentication  
information. The local end maintains a list of authorized user accounts and passwords.  
To add a user to the list, use the following command:  
create account pppuser <name> {encrypted} {<password>}  
Encapsulation  
The packets passed over the PPP link can use either bridged or routed encapsulation.  
You would use bridged packets if you plan to have VLANs span the PPP link. You  
would use routed packets if the link connects two different routed networks or separate  
VLANs.  
Using bridged packets allows the VLAN tags to be carried across the PPP link. Bridged  
packets are transported using the PPP Bridging Control Protocol (BCP), described in  
RFC 2878. When the encapsulation is set to BCP, 802.1Q and 802.1p information is  
preserved and transported across the link. On a WM-4T1i module, a VLAN may only  
contain one BCP encapsulated link.  
Routed packets are transported across a PPP/ MLPPP link using IP Control Protocol  
(IPCP), described in RFC 1332. This is the encapsulation that is familiar to most users of  
PPP. The routed packets do not contain Ethernet headers so cannot preserve VLAN  
tags. The IP addresses used for the PPP/ MLPPP link are taken from the IP address  
assigned to the VLAN at each end of the link. The VLAN that contains the IPCP  
encapsulated PPP/ MLPPP ports cannot contain other ports. In other words, the only  
ports allowed in the VLAN are those that make up the IPCP encapsulated link.  
You must have one and only one encapsulation type configured on a PPP/ MLPPP link.  
Setting BCP encapsulation off implies that IPCP encapsulation is on. The default setting  
is BCP encapsulation on and IPCP encapsulation off. To configure encapsulation, use  
the following command:  
3-4  
WM-4T1i Module Installation and User Guide  
 
                         
Configuring a PPP/MLPPP Link  
config ppp [bcp [on | off] | ipcp [on | off]] [ports <portlist> |  
multilink <groupname>]  
PPP/MLPPP Configuration Commands  
Table 3-1 describes the commands used to configure a PPP/ MLPPP link.  
Table 3-1: PPP/MLPPP Configuration Commands  
Command  
Description  
config multilink <groupname> add ports  
<portlist>  
Adds ports to a multilink group.  
config multilink <groupname> delete ports  
<portlist>  
Removes ports from a multilink group.  
config ppp authentication [off | chap | pap |  
chap-pap]  
[ports <portlist> | multilink <groupname>]  
Sets the authentication method for a PPP link  
or a MLPPP multilink group. The default setting  
is to use no authentication.  
config ppp [bcp [on | off] | [ipcp [on | off]] [ports Sets the encapsulation method for a  
<portlist> | multilink <groupname>]  
PPP/MLPPP link. You cannot set both to on, or  
both to off. Configuring bcp on implies ipcp off;  
configuring ipcp on implies bcp off. The default  
setting is bcp on.  
config ppp user <username> {encrypted}  
<password>  
Sets the username sent to the remote end of a  
PPP/MLPPP link for authentication.  
[ports <portlist> | multilink <groupname>]  
config vlan <vlan> add multilink <groupname> Adds an MLPPP multilink group to a VLAN.  
config vlan <vlan> delete multilink  
<groupname>  
Removes an MLPPP multilink group from a  
VLAN.  
create account pppuser <name> {encrypted}  
{<password>}  
Adds a username that will be accepted by the  
local end during authentication.  
create multilink <groupname>  
delete multilink <groupname>  
delete account pppuser <username>  
Creates a multilink group.  
Deletes a multilink group.  
Removes a username from the local  
authentication list.  
disable multilink <groupname>  
enable multilink <groupname>  
Disables a multilink group.  
Enables a multilink group (and enables all  
ports in the group).  
WM-4T1i Module Installation and User Guide  
 
3-5  
                               
Configuring PPP and MLPPP  
Table 3-1: PPP/MLPPP Configuration Commands (continued)  
Command  
Description  
restart multilink <groupname>  
Restarts multilink group. Configuration changes  
made to an enable multilink group will not take  
effect until the group is restarted.  
unconfig ppp port <portlist>  
Resets the port to the default PPP  
configuration; no authentication and BCP  
encapsulation.  
Monitoring PPP/MLPPP Links  
The following commands monitor the status of the PPP and MLPPP links.  
Table 3-2: PPP/MLPPP Show Commands  
Command  
Description  
show multilink <groupname>  
Displays the configuration of the multilink  
group.  
show multilink [<groupname>] stats {detail}  
Displays multlink group statistics.  
show multilink [<groupname>] t1 alarms {detail} Displays T1 alarm status for multilink groups.  
show multilink [<groupname>] t1 errors Displays T1 error statistics for a multilink  
[near-end | far-end] [totals | intervals | current] group.  
show ppp {<portlist>} {detail}  
show accounts pppuser  
Shows PPP configurations.  
Show the PPP accounts on the switch.  
PPP/MLPPP Configuration Examples  
The following examples show how to configure multilink groups.  
Configuring a Bridged PPP/MLPPP Link Example  
The following example shows how to configure a BCP-encapsulated multilink group.  
BCP is the default encapsulation, so it is not explicitly included in this example. The  
config ports t1 clocksourcecommand is included to show where you might need  
to configure the T1 parameters for your link. Each T1 port in the multilink group will  
3-6  
WM-4T1i Module Installation and User Guide  
 
                       
PPP/MLPPP Configuration Examples  
have the same T1 and PPP configurations. If you change the configuration for a single  
port, the change will affect the entire group.  
VLAN alpha  
tag = 1001  
Multilink bcp_example  
encapsulation = BCP  
T1 port 4:1  
PPP  
To  
switch  
#2  
T1 port 4:2  
PPP  
PPP  
T1 port 4:3  
Switch #1  
XM_007  
Figure 3-1: BCP multilink example  
config default delete ports 4:1-4:3  
create vlan alpha  
config alpha tag 1001  
create multilink bcp_example  
config ports 4:1-4:3 t1 clocksource internal  
config bcp_example add ports 4:1-4:3 tag  
config alpha add multilink bcp_example  
enable bcp_example  
Configuring a Routed PPP/MLPPP Link Example  
The following example shows how to configure a IPCP-encapsulated multilink group.  
The VLAN that contains the IPCP-encapsulated multilink group cannot contain any  
other ports.  
WM-4T1i Module Installation and User Guide  
 
3-7  
 
Configuring PPP and MLPPP  
VLAN beta tag = 1001  
IP address = 10.10.10.1/24  
Multilink ipcp_example  
encapsulation = IPCP  
T1 port 4:1  
T1 port 4:2  
T1 port 4:3  
PPP  
PPP  
PPP  
To  
switch  
#2  
Switch #1  
XM_008  
Figure 3-2: IPCP multilink example  
config default delete ports 4:1-4:3  
create vlan beta  
config beta tag 1001  
config beta ipaddress 10.10.10.1/24  
create multilink ipcp_example  
config ipcp_example add ports 4:1-4:3 tag  
config ppp ipcp on ports 4:1-4:3  
config beta add multilink ipcp_example  
enable ipcp_example  
3-8  
WM-4T1i Module Installation and User Guide  
 
Index  
Numerics  
802.1p  
802.1Q  
E
3-4  
3-4  
encapsulation  
BCP  
3-4  
3-4  
3-4  
2-4  
configuring  
IPCP  
ESF (Extended Super Frame) T1 line framing  
A
alarms  
2-2  
2-4  
2-4  
3-3  
alternate mark inversion (AMI)  
AMI linecoding  
authentication  
F
framing  
2-4  
2-4  
2-4  
ESF (Extended Super Frame)  
SF (Super Frame)  
B
B8ZS linecoding  
BCP encapsulation  
2-4  
3-4  
2-4  
3-4  
I
bipolar eight zero suppression (B8ZS)  
bridged PPP links  
IPCP encapsulation  
3-4  
L
C
LEDs  
cable length  
2-2  
T1 port  
1-4  
2-4  
2-4  
2-4  
2-4  
Challenge Handshake Authentication Protocol  
(CHAP)  
CHAP  
clock source  
configuring  
encapsulation  
T1 port  
conventions  
notice icons, Preface  
text, Preface  
linecoding  
AMI  
B8ZS  
loopback detection  
3-3  
3-3  
2-3  
3-4  
2-1  
M
MLPPP  
multilink group  
adding to VLAN  
Multilink PPP (MLPPP)  
3-1  
3-2  
3-2  
3-1  
1-vi  
1-vi  
I
 
 
P
PAP  
3-3  
3-1  
3-1  
3-3  
Point-to-Point Protocol (PPP)  
PPP  
PPP authentication protocol (PAP)  
PPP links  
bridged  
routed  
PPP user accounts  
PPP username  
3-4  
3-4  
3-4  
3-3  
PPP/ MLPPP  
configuration commands (table)  
3-5, 3-6  
R
RFC 1332  
RFC 2878  
routed PPP links  
3-4  
3-4  
3-4  
S
SF (Super Frame) T1 line framing  
2-4  
T
T1 port  
alarms  
cable length  
clock source  
configuration commands (table)  
configuring  
framing  
LEDs  
linecoding  
2-2  
2-2  
2-3  
2-5  
2-1  
2-4  
1-4  
2-4  
2-4  
2-10  
loopback detection  
monitoring commands (table)  
U
user accounts, PPP  
username, PPP  
3-4  
3-3  
V
VLAN tags  
3-4  
II - INDEX  
 
Index of Commands  
C
R
config multilink add ports  
config multilink delete ports  
config ports t1 alarms  
config ports t1 cablelength  
config ports t1 clock source  
config ports t1 fdl  
3-5  
3-5  
2-5  
2-5  
2-5  
2-5  
2-5  
2-5  
2-5  
2-5  
3-5  
3-5  
3-5  
3-5  
3-5  
3-5  
3-5  
3-5  
restart multilink  
3-6  
S
show accounts pppuser  
show multilink  
3-6  
3-6  
3-6  
3-6  
3-6  
2-10  
2-10  
2-10  
2-11  
2-11  
2-10  
3-6  
config ports t1 framing  
config ports t1 lbdetect  
config ports t1 linecode  
config ports t1 yellow  
config ppp authentication  
config ppp bcp  
config ppp ipcp  
config ppp user  
config vlan add multilink  
config vlan delete multilink  
create account pppuser  
create multilink  
show multilink stats  
show multilink t1 alarms  
show multilink t1 errors  
show ports stats  
show ports t1 alarms  
show ports t1 configuration  
show ports t1 errors  
show ports t1 info  
show ports t1 stats  
show ppp  
U
unconfig ppp  
3-6  
D
delete account pppuser  
delete multilink  
disable multilink  
disable ports t1 loopback  
3-5  
3-5  
3-5  
2-10  
E
enable multilink  
enable ports t1 loopback  
3-5  
2-10  
Index of Commands - i  
 
 
ii - Index of Commands  
 

Earthquake Sound Speaker IQ1500 User Manual
Electro Voice Speaker System FRI+152 94 User Manual
Ericsson Computer Drive UM10067 User Manual
Ericsson Two Way Radio MTL SX User Manual
Euro Pro Vacuum Cleaner HV118H User Manual
FujiFilm Digital Camera XP 170 User Manual
Furman Sound Stereo Receiver Elite 15 User Manual
GE Double Oven JGRP20 User Manual
Gemini Musical Instrument PMX 1100 User Manual
Goodman Mfg Air Conditioner CE COMMERCIAL SPLIT SYSTEM AIR CONDITIONER User Manual