I did the upgrade with no ill effects.
If anyone is interested, this is from VRT.TXT, one of the files included in the upgrade:
Firmware Date : January 25,2002
Current Firmware : Version 1.42.3
Product PartNo : BEFSR11/BEFSR41/BEFSRU31
Ver #. Date Description
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1.42.3 Jan 25,01 1. Router can support PCs with small MTU settings
to configure the router.
2. Supports Applying settings without rebooting (Password, DHCP,
MAC Filter, Forwarding, DMZ, MAC Addr.Clone)
3. Added DNS and WINS setting in DHCP User Interface
page.
4. Support for UPnP forwarding loopback
5. Support for multi-IPSec pass-through
6. Fixed Nortel VPN pass-thru
7. Forced MTU enabled and size = 1492,when PPPoE is enabled
8. Added DHCP Lease time for LAN connections
1.41 Dec 19,01 1. Added UPnP Support
2. Added PPTP client for European users.
3. Updated Web upgrade utility
4. New WAN connection setting Interface in the SETUP page.
5. Supports MSN messanger 4.5 (voice and file transfer
without DMZ setting)
1.40.2 Oct 24,01 1. Fixed DHCP server probem that assign one IP address to 2 PCs
2. Fixed traceroute problem under router mode(traceroute can not
find out the Linksys router)
3. Fixed ip filter problem when start ip is bigger then end ip
4. Fixed Log radio disappear when click Cancel button on Log UI page
5. Fixed some time user can see the UI page without password problem
6. Fixed PCC prompts "This version needds the special router" when installation
7. Change the aging time of AOL application (#5190) connection to 90 minutes.
8. Modify UI pages to fix the banner problem in Netscape 4.7, 6.0
1.40.1 Sept 10,01 1. Support Zone Alarm Pro firewall and PC-cillin anti-virus software
1.39 June 5, 01 1. Support Fragmented packet pass through
2. Speed up throughput rate
3. Support MSN Messenger
4. Support VPN IKE
1.38.5 Apr 12, 01 1. Modify PPPoE and RAS action include Setup and Status help UI
(Keep Alive will always try to keep the line alive)
2. Add SPI (Stateful Packet Inspection) function in Filter page
3. Deny WAN side DNS relay request
4. Fix DNS relay access trap (port 1200, 1400) problem
5. When using PPPoE login, doesn't WAN Gatewayand Subnet Mask in Status page
6. Add MTU(maximum transmission unit) function in "Filter" page
7. Modified Korea DHCP problem: if router does not has host name, send WAN
MAC as hostname to get ip
8. Add "Port Triggering" function in Forwarding page
9. Fix DNS relay under PPPoE problem
10. Fix DNS relay under DMZ setting problem
11. support multi-LAN-host using same port to connect to same server
12. Fix Forwarding LAN PPTP server problem
13. Fix DNS relay under PPPoE dial on demand disconnected problem
14. Change Forwarding LAN server IP range from 0~254 to 0~255
15. Add PPPoE and RAS keep alive redial period setting field in "Setup" page
16. Support space on Web UI input page
17. Support long dhcp lease time in WAN interface
18. Speed up throughput rate
19. Add "multicast pass through" option in Filter UI page
20. Modified Max MTU setting value of PPPoE from 1446 to 1492.
21. Speed up throughput under PPPoE.
22. Support 3com adsl modem.
1.37 Jan 3, 01 1. Modified the access log message to import to Excel
2. Add the RAS function
3. Move Log page to first banner.
4. Add a ?MAC Address Clone? page
5. Fixed NEWS server connection problem
6. Add a Note message in ?Setup? page for PPPoE and RAS
7. Modified the HTTP module
8. Modified LCP_request time to avoid the timeout issue.
Timeout increased to 15 seconds.
9. RAS Plan: When choose 256k, it will show 256k even refresh.
10. RAS help is in the setup help.
11. More detail is in the RAS help.
12. Fixed Forwarding protocol problem.
13. Fixed lost connection of SSH problem.
14. Support multicast traffic - FTP downloads
15. Fixed system lock up when filter is setted
16. Fixed press "Continue" can't go back to pre-setting page problem
17. Keep the DHCP Table when system reboots.
18. Change the size of incoming log table from 200 to 70.
19. Fixed Broadcast ping problem (response src IP is wrong)
20. Fixed Broadcast trap IP problem.
21. Fixed WIN CE DHCP problem (UDP checksum error)
22. Adjusted TFTP upgrade password length.
23. Add protocol selection in Forwarding page
24. Add protocol selection in Filter page
25. Add MAC Filter in Filter page(50 entries)
26. Resolved RAS Problem when DMZ is enabled.
27. Resolved Remote Management problem
28. Resolved Failed UI Link problem.
1.36 Oct 5, 00 1. Firmware now supports BEFSRU31
2. Address other VPN issues.
3. Updated Help files
4. Deals with Canada connections Sympatico.
v1.35 Sept 8,00 1. Fixes issues with Danmark
2. Modified the PPPoe function
v1.34 Aug 17,00 1. Changed Router name to Host name.
2. New option of incoming and outgoing logs
3. New option of Keep Alive Connection
v1.33 July 18,00 1. Fixes the DHCP Problem.
v1.32 July 14,00 1. Change the setting of filter and forwarding from single entry to range
2. Solve the ping problem from WAN to a LAN host.
3. Add help contents about IPSec / PPTP pass-thru, remote mangement, and range setting
4. Do some modification for the IPSec+PPPoE problem.
5. Add access log in the STATUS page
6. Add Leased time display in the STATUS page
7. Add user-defined WAN MAC address setting in the SETUP page
8. Add Remote management feature ( Currently, the TCP port is fixed as 80)
9. Add Remote management / IPSec pass-thru / PPTP pass-thru disable/enable
in the FILTER page
10. Fixed the internal loopback bug under PPPoE or DHCP environment.
V1.30 June 9,00 1. Resolved issues going to some websites ie.
www.match.com
2. Resolved the FTP Data Corruption
3. IPSec-Passthru
4. Extended the username and password for PPPoE up to 63 character.
5. Resolved the data corruption problem
V1.23 Apr 28,00 1. Change the 'Block WAN request' default setting as ENABLE.
Fixed the web browsing problem like
www.pcconnection.com
<
http://www.pcconnection.com> with PPPoE connection.
2. Refine the User Interface in both setup and forwarding page.
3. Fixed DMZ loopback problem
4. Modified packet handling
5. Fixed issue using VPN Server behind the router
V1.22 March 31,00 1. Add the description about PPPoE and "Block WAN request"in the help.
2. Solved the IP address 255 problem
3. Add the "Connect on Demand" feature for PPPoE
4. Support internal loopback feature for accessing the internal servers
via the WAN IP address.
5. Inhibit the ability to upgrade firmware from WAN port.
6. Build in a Java-based TFTP upgrade utility. User can find this on the
help page.
7. Support multi-player to play HalfLife.
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