Upgradation of PTCL modems

where can i find new firmware image onto the ADSL Router of ZXDSL 831DV2.1 modem?

please post links to upgrade page... i will edit this post regularly.

SHIRO Firmware Upgradation Procedure link

http://cpe.ptcl.net/

dont upgrade it it might not work after upgrade...!

Which routers upgrades are available and which are essential for better perofrmance.

just Shiro firmware update is available by PTCL

If firmware is upgraded then it can be rollback to previous one or not?

not so sure about it!! might be!!