
                                d i g i t a l



                                 DIGITAL ATMswitch 900 Firmware Release Notes
                                                         Firmware Version 1.3
                                                                 December 1997



These release notes provide information about the DIGITAL ATMswitch 900 
firmware.  This release supports both the ATMswitch 900F and the 
ATMswitch 900T modules.  Note that references to firmware version 2.4 in 
the documentation are incorrect.  These references should indicate 
firmware version 1.3.  


Important: Read This First

You should check that your ATMswitch 900 firmware release is the latest 
version by checking the latest firmware release notes that are available 
online from the DIGITAL FTP site and the Network Product Business Web 
Site.  If it is not the latest version, you should upgrade it immediately 
as described in the Installation and Configuration book.  To determine 
the current firmware versions, use the versions command at the 
ATMswitch-> console prompt.  


Introduction

This document contains important notes for the ATMswitch 900 module, 
including information about:  

	o  Firmware locations and upgrades 

	o  Configuration guidelines 

	o  Support for modular PHY loop timing 

	o  Known problems 

	o  Unsupported features 

	o  Online information access 


How to Get a Copy of ATMswitch 900 Firmware

The latest firmware kit is located in a release area at the DIGITAL FTP site 
(ftp.digital.com).  Copy the image to your system using these commands:  

	# ftp ftp.digital.com

	username: anonymous 
	password: (your Internet address)

	ftp> cd /pub/DEC/GIGAswitchATM 
	ftp> bin 
	ftp> get file-name file-name  
	ftp> bye

where file-name is the name of any file that you are copying.  

For example, if you are using a UNIX system, you might copy the A900Rn_n.tar 
file where  n_n indicates the version number (for example, V1.0 would be 1_0).  
To unpack the new image, use the following UNIX command:  

	# tar -xvf A900Rn_n.tar 

This command creates a subdirectory named A900Vn_n within your current 
working directory.  The following files are unpacked into the A900Vn_n 
subdirectory:  

	A900Rnn.CTL 		Sample control file 

	A900Rnn.BIN 		Application image 

	A900Rnn.ROM 		Kernel image 

If you are using another operating system, you might want to copy the 
files listed in the above table.  


Upgrading the Firmware

For more detailed instructions about the firmware upgrade procedure, see 
the Upgrading the Firmware section of the Installation and Configuration 
book.  


Configuration Guidelines

Slot Restrictions for the DIGITAL MultiSwitch 900

If you are using a DIGITAL MultiSwitch 900 (formerly DEChub 900 
MultiSwitch), the ATMswitch 900T module does not have any slot 
restrictions.  

However, the ATMswitch 900F module can only be configured in slots 7 or 8 
of the DIGITAL MultiSwitch 900.   If the module is not in an appropriate 
slot, you will see the following LED indications:  

	o  Module OK LED is off.   

	o  PHY3 and PHY6 LEDs are amber. 

	o  FRU4 and FRU5 LEDs are amber. 


Port Restrictions for the DIGITAL MultiSwitch 900

If you are directing ports 5 through 8 of the ATMswitch 900 module to 
the backplane of a DIGITAL MultiSwitch 900 for interconnection to other 
ATMswitch 900 modules, the ports must be connected to the same numbered 
port on the connected modules.  For example, port 5 on one ATMswitch 900 
module must be connected to port 5 on an interconnected ATMswitch 900 
module.  


LAN Emulation

If you are using LAN Emulation (LANE), you should be aware of the following 
guidelines:  

	o  To allow access from other switches to the LECS, create a static 
	   route between the switch that has the LECS enabled and the 
	   well-known LECS address.  The static route's forwarding slot 
	   should be set to 1 and the forwarding port should be set to 0.  
	   This route must be exported.  

	o  When using LANE over an E1 link, the BUS rate limit must be set 
	   to less than 500 kb/s. 

	o  12 emulated LANs (ELANs) is the maximum number supported.  The 
	   BUS rate for each ELAN should not exceed 600 kb/s.  


Constant Bit Rate Circuits

When configuring constant bit rate (CBR) circuits for E1, E3, T1, or T3 
links, set the CBR link rate to a value that is less than 70% of the total 
allowable link rate.  

The maximum CBR bandwidth is 400 Mb/s.  


Maximum Sustained Throughput

800 Mb/s is the maximum sustained throughput supported.  Traffic might be 
discarded when this value is exceeded.  


Virtual Circuit Range Support

The ATMswitch 900 module supports 2000 switched virtual circuits and 2000 
permanent virtual circuits total.  These virtual circuits can be distributed 
across all ports in any fashion.  If you are using ports 7 or 8, these ports 
only support up to 1700 virtual circuit identifiers (VCIs).   


Maximum VCI Ranges for a Link

If the remote node has a limited virtual circuit identifier (VCI) range and 
the VCI ranges are not exchanged with the switch using ILMI link-up 
procedures, you might have to configure the maximum VCI range with the 
set_maxlinkvci command.  This command prompts you for the line card number 
(always 1 for the ATMswitch 900 module), the head (or port) number, and the 
maximum VCI.   The maximum VCI value should be the maximum VCI of the remote 
node.  


Setting the Module Startup Mode

To set the module startup mode, use the setStartupMode('mode') command.  The 
value for mode can be one of the following:  

	o  0 (zero) indicates normal startup mode with self-test.  

	o  F indicates normal startup mode without self-test.  

	o  L indicates image load.  If you use this startup mode, you must 
	   reset the startup mode to 0 or F and reboot the switch.  


Slot Designations When Using ATM Commands or MIBs

When using ATM commands or MIBs, the slot value is always 1 and does not 
indicate the slot in the DIGITAL MultiSwitch 900 into which the module is 
plugged.  


Support for Modular PHY Loop Timing

The ATMswitch 900 firmware supports the selection of the transmit timebase.  
SNMP already supports read-write access of the transmit timebase for DS3, 
DS1, E3, and E1.  The menu interface also supports read-write access to the 
transmit timebase for all interfaces with menu option 3.8 (Modify Transmit 
Clock Generation Source).   


Supported modPHY Types

The following modular PHY (modPHY) cards are supported for this release:  

	modPHY Type 				Part Number 
	-----------				-----------
	E1 (2 Mb/s) short reach TP 		DAGE1-AA 

	E3 (34 Mb/s) coaxial 			DAGGE-AA 

	DS1/T1 (1.54 Mb/s) short reach TP 	DAGT1-AA 

	DS3/T3 (44 Mb/s) coaxial 		DAGGT-AA 

	STS-3c (155 Mb/s) UTP/ScTP 		DAGGU-AA 

	OC-3 (155 Mb/s) MMF 			DAGGM-AA 

	OC-3 (155 Mb/s) SMF 			DAGGS-AA 


Transmit Timebase Selection and Nonvolatile Parameter Storage

Transmit timing sources are established for each link.  Each physical link 
can be configured to derive its transmit timing from either a local 
oscillator or the recovered receive clock.  Local timing specifies that the 
transmit timing is derived from the local oscillator.  Loop timing specifies 
that the transmit timing is derived from the recovered receive clock.  


System Behavior at Switch Reboot and Across modPHY Hotswap

When the switch is rebooted, the nonvolatile records for each populated link 
are examined.  If a record is found for the PHY type detected, the stored 
setting is used.  If a record is not found, local timing is used.  This 
implies that if a PHY type is changed while the switch is powered down, 
switch initialization will not necessarily yield the default setting.  

The same sequence of actions occurs if a link is unpopulated at switch 
powerup, but is populated later.  

When modPHY hotswap yields a PHY type change, the new link is initialized 
with the default setting (local timing).  When modPHY hotswap does not result 
in a PHY type change, the link is reinitialized with its last known setting 
(if it is not overridden by a condition described in the next section).  Note 
that hotswap does not trigger a nonvolatile record update.  So, a subsequent 
switch reboot might, by virtue of a previously stored record for that link 
and type, change the timing setting.  


Effect of Port Conditions on the Transmit Timebase Setting

Two conditions, loss of signal and loss of frame, will force a loop-timed 
link to revert to local timing.  Subsequent clearing of the condition will 
force such a port back to loop timing.  Neither of these forced transitions 
will cause a nonvolatile record update.  


Known Problems

References to Firmware Version 2.4

Note that references to firmware version 2.4 in the documentation are 
incorrect.  These references should indicate firmware version 1.3.  


reset_factory_defaults Command Is Invalid

The reset_factory_defaults command is invalid.  Use the 
restart_factory_defaults command instead.  


Password Protection for Telnet Access

The default passwords described in the ATMswitch 900 Management book is 
incorrect.  This section provides the correct information about the 
password protection feature.  


Accounts and Default Passwords

The following two accounts can be used for password protection:

	Account/login name 	Default password 
	------------------	----------------
	user			username

	manager			managername

These accounts (login names) cannot be changed.  You are only required to 
use a named account when password protection is enabled.  Passwords can be 
changed as described below.

Using Password Protection

It is important for security reasons to change the default passwords of 
both accounts if you want password protection.  Note that passwords are 
never used on the local console terminal, which is secured only by limiting 
physical access.  

The password_enable command or the menu interface can be used to activate 
password operation.  Both the user and the manager accounts are enabled 
(or disabled) together through either method.   Password protection is 
disabled in the default configuration.  

When passwords are used, the Telnet login process (using default values) 
resembles the following example:  

	ATMswitch login:  user

	Password: username

	ATMswitch->

The user and manager accounts have equal access and control over the 
ATMswitch 900 module's functions and characteristics.  The difference 
between the accounts is the password, which is useful in a large 
organization.

Changing Passwords

The passwords for both accounts can be changed whether or not you are 
logged in to either account.  However, you must know the old password 
to change a password.

The password_set command only changes the user account password.  The 
menu interface lets you change both account passwords.

If you lose your passwords, restart your module with the factory defaults 
by using the appropriate ATMswitch 900 INSTALLATION MENU option or the 
restart_factory_defaults command described in the Installation and 
Configuration book.  


UNI Version and IISP Links

When there is an IISP link between two DIGITAL ATM switches, the UNI 
version is specified as UNI 3.1 by default.  Do not specify any UNI 
version other than UNI 3.1.  


Telnet Session on Existing Connection

Invoking a Telnet session to a switch that is already used by a serial 
line connection causes the initial session to be locked out until the 
Telnet session is terminated.  


Unsupported Features in This Release

The following features are not supported in this release:  

	o  IP switching 

	o  Rate-based flow control 

	o  EFCI 

	o  SLIP/OBM port 


Accessing Online Information

Further information on this network product or topic is available on the 
Network Product Business Web Site.  The Web Site maintains a rich set of 
up-to-date information about DIGITAL networking products, technologies, 
and programs.  The Web Site can be reached at geographic locations via 
the following URLs:

	Americas Network Product Business Home Page
		http://www.networks.digital.com/ 

	Europe Network Product Business Home Page
		http://www.networks.europe.digital.com/ 

	Asia Pacific Network Product Business Home Page
		http://www.networks.digital.com.au/

	Digital Equipment Corporation Home Page
		http://www.digital.com/ 

To get firmware and MIB information, choose the "Technical Information" 
link, and from there choose the "Technical Information (Drivers, Manuals, 
Tech Tips, etc.)" link.

























 Digital Equipment Corporation 1997. All rights reserved. Printed in U.S.A.

DEC, DIGITAL, and the DIGITAL logo are trademarks of Digital Equipment 
Corporation.
