Grandstream UCM6104 IP PBX Firmware 1.0.11.27

Enhancements:

- Added ability to sort extension status on web UI [EXTENSION STATUS IMPROVEMENT]

- Added one click enable / disable feature code [FEATURE CODE SELECTION IMPROVEMENT]

- Added Uruguay time zone support [URUGUAY TIME ZONE SUPPORT]

- Added distinctive ring tone support [DISTINGCTIVE RING TONE SUPPORT]

- Added special character support for SFTP client account [SFTP CLIENT ACCOUNT SPECIAL CHARACTRE SUPPORT]

- Added destination directory support for data sync [DESTINATION DIRECTORY]

- Added ring group music on hold [RING GROUP MUSIC ON HOLD]

- Added CDR multi-email / time condition support [CDR MULTI EMAIL AND SPECIFIC TIME DOWNLOAD SUPPORT]

- Added blacklist anonymous call block [BLACKLIST ANONYMOUS CALL BLOCK]

- Added ability to sort selected extension in eventlist [EVENTLIST: SORTING SELECTED EXTENSION]

- Added banned user list for web UI login attempts [WEB UI LOGIN IMPROVMENT]

- Added Email template support [EMAIL TEMPLATE]

- Added outbound route country restriction [OUTBOUND ROUTE: COUNTRY RESTRICTION]

- Added external disk usage alert option [EXTERNAL DISK USAGE ALERT]

- Added range IP input support for dynamic defense white list [DYNAMIC DEFENSE: WHILTE LIST RANGE IP SUPPORT]

- Added blacklist support for Fail2ban [FAIL2BAN: BLACKLIST]

- Added ability to reboot device from zero config page [ZERO CONFIG: REBOOT DEVICE]

- Added GXP1628B template for zero config [ZERO CONFIG: GXP1628B SUPPORT]

- Added PIN group support [PIN GROUP SUPPORT]

- Added H-Mobile PMS support [H-MOBILE PMS SUPPORT]

- Added call queue custom prompt support [CALL QUEUE: CUSTOM PROMPT]

- Added call queue retry time support [CALL QUEUE RETRY TIME]

- Added enhancement for anonymous call on SIP trunk [ADDED ENHANCEMENT FOR ANONYMOUS CALLS ON SIP TRUNK]

- Added "call-info" SIP header for GXP phone paging mode [ADDED KEEP THE “CALL-INFO” SIP HEADER FROM GXP PHONE USING PAGING MODE]

- Added authentication for inbound SIP INVITE from SIP trunk (for BroadWorks)

Bug Fixes:

- Fixed PJSIP pool caused crashing issue

- Fixed Service check function doesn’t work issue

- Fixed CDR auto download by month CSV file empty issue

- Fixed CDR API Sub_CDR_1 field is duplicate on JSON file

- Fixed Trunk caller ID name only allow to input letter, digits and space

- Fixed Trunk call back auto recording file abnormal issue

- Fixed Trunk call back auto recording doesn’t play prompt issue

- Fixed Trunk call back only has Chinese and English voice prompt

- Fixed Trunk DOD tooltips unclear issue

- Fixed Trunk incoming call drops in 30 seconds

- Fixed Trunk call back using failover trunk on outbound call will fail

- Fixed Trunk caller ID with special characters will cause UCM crash

- Fixed Trunk inbound route blacklist doesn’t block call correctly issue

- Fixed Trunk inbound route mode 1 strip value is null

- Fixed Trunk inbound route privilege level is hidden when dial trunk is enabled

- Fixed Trunk inbound call transfer fails with NEXTIVA trunk when PAI is enabled

- Fixed Trunk: inbound route black list feature code prompt doesn’t match status issue

- Fixed Trunk: disable qualify will cause outbound call fail

- Fixed Trunk: outbound route custom dynamic route tooltips

- Fixed Trunk: outbound route custom dynamic route cannot display full details when it is too long

- Fixed Register Trunk SIP message abnormal behavior issue when “TEL URI” option is enabled

- Fixed Register Trunk NAT tooltips misleading issue

- Fixed Register Trunk extension NAT option does not take effect when transport set to TCP

- Fixed Register Trunk will switch to alternative IP when UCM receives any 5xx and 6xx response

- Fixed Register Trunk: UCM doesn’t send registration update at desired timer

- Fixed Register Trunk: UCM doesn’t send correct caller ID and name

- Fixed Callback outbound password doesn’t take effective when using DISA in callback

- Fixed Active Call page will display incorrect call forward status when “Auto Record” is enabled

- Fixed Active Call page will display incorrect call log when two extensions dial to parking lot

- Fixed Active Call page will generate two call records when answering ring group calls using feature code

- Fixed Active Call page will display incorrect extension when call forward is enabled

- Fixed Active Call page abnormal display when calling into paging / intercom extension

- Fixed Active Call callee carries caller’s caller ID name for CC feature

- Fixed Active Call page fax extension display issue

- Fixed Active Call page IAX extension callee ID and name display issue

- Fixed Active Call page doesn’t display corresponding spy mode

- Fixed Active Call will display callee as unknown when using one key dial to reach voicemail

- Fixed Active Call page will display two records when follow me members enable auto recording

- Fixed Active Call page display issue after clicking Apply Changes

- Fixed Active Call page cannot hangup when monitored extension becomes abnormal

- Fixed Active Call page display issue when callee enables ring both

- Fixed Active Call page display issue when a call is transferred to call queue operator extension

- Fixed Active Call page display issue when call queue or ring group has IAX extension member answers the call

- Fixed Active Call FXO port shows in use when removing PSTN line from UCM

- Fixed Active Call doesn’t have error prompt when monitoring non registered extension

- Improved Active Call page display for transfer call

- Improved Active Call page display for direct dial extension when calling through register trunk

- Fixed CDR display issue when CCSS call is rejected

- Fixed CDR caller number tooltips error

- Fixed CDR MCB invite doesn’t have independent record

- Fixed CDR and voice recording not show callee issue if analog line has no CID

- Fixed CDR inbound route mode 1 will have incorrect record

- Fixed CDR recording stops after a call is parked

- Fixed CDR incorrect record when dialing FXS extension through paging / intercom group

- Fixed CDR incorrect record when using follow me for remote extension

- Fixed CDR cannot display ring group record when all members in the ring group rejects the call

- Fixed CDR cannot display trunk name when inbound call coming through analog / digital trunk

- Fixed CDR: GXP2160 doesn’t generate record when using line button to dial

- Fixed CDR: invite IAX / FXS extension into conference room will have extra CDR record

- Fixed CDR incorrect record for call queue members

- Fixed CDR display error when filter using SIP call

- Fixed CDR incorrect record when calling into IVR has no extension number

- Fixed CDR peer / IAX trunk will generate two records

- Fixed CDR generates two records when follow me member has FXS / IAX extension

- Fixed CDR callee displays as ‘s’ when it is a FAX extension coming through IVR

- Fixed CDR search result doesn’t match search settings

- Fixed CDR doesn’t generate record when using FXS extension

- Fixed CDR will display no call detail if call prefix contains character ‘#’

- Fixed CDR display issue when user calls conference room

- Fixed CDR display issue when creating customized prompt

- Fixed CDR display issue when ring simultaneously for external number is enabled

- Fixed CDR display issue when using dial by name on inbound call

- Fixed CDR doesn’t have call details when using AMI command originate calls

- Fixed CDR FXS extension ring simultaneously will have incorrect record when ring simultaneously is enabled

- Fixed CDR will have incorrect record when inbound call to external number

- Fixed CDR: Chinese caller ID name will cause CDR record missing

- Fixed CDR: incoming call from analog trunk without CID will cause no CDR and voice record

- Fixed CDR API: setting TLS bind address to IP or domain will cause error prompt issue

- Fixed CDR API: cannot delete permitted IP address

- Fixed CDR API: Sub_CDR_1 field is duplicated in download JSON file

- Fixed Extension Can Reinvite tooltips issue

- Fixed Extension Caller ID Name option incorrect tooltips issue

- Fixed Extension enable WebRTC option language error

- Fixed Extension: cannot reboot phone when AuthID is different than Extension number

- Fixed Extension: incorrect WebRTC option in IAX and FXS extension page

- Fixed IAX Extension: batch add IAX extension shows “wrong account or password”

- Fixed IAX and FXS extension does not send account name when using Email to User

- Fixed FXS extension voicemail doesn’t require password issue

- Fixed FXS extension web page error prompt when modifying analog station

- Fixed FXS Hotline option doesn’t have default value

- Fixed FXS echo canceler doesn’t work on flash dial

- Fixed Basic Call wrong CID for internal calls when Ring Simultaneously is enabled

- Fixed Basic Call drops because SIP INFO is rejected by UCM

- Fixed Basic Call ring simultaneously with external number will cause CID display issue

- Fixed Basic Call cannot record 3-way conference

- Fixed Basic Call cannot use feature code *0 to cancel attend transfer

- Fixed Basic Call error prompt when using feature code *40 to add blacklist

- Fixed Basic Call attend transfer Chinese language prompt error

- Fixed Basic Call: parking call in occupied parking lot will connection two calls together

- Fixed Basic Call: UCM cannot differentiate a call received on specific inbound route

- Fixed Basic Call: extension will have abnormal status when previously delete and re-create the same extension

- Fixed Basic Call: UCM cannot display extension status correctly when extension re-register on UCM

- Fixed Basic Call: UCM cannot display extension status correctly after UCM reboots

- Fixed Basic Call: video call with different codec will cause preview display abnormal

- Fixed Basic Call: codec negotiation will fail if UCM has 183 response

- Fixed Basic Call: cancel call from caller side when callee enables unconditional forward will cause UCM crash

- Fixed Basic Call: blind transfer will cause UCM to display incorrect caller ID

- Fixed Basic Call: CCSS fail to call back when TEL URL via trunk is enabled

- Fixed Basic Call: CCSS publish message exception caused system crash

- Fixed Basic Call: UCM doesn’t use same codec from negotiation when receiving 183 response

- Fixed Basic Call: caller ID number will cause CCSS fail

- Fixed Basic Call: time condition doesn’t take effect

- Fixed Basic Call: hold call feature issue

- Fixed BLF&Eventlist: when one member picked up call from Ring Group, UCM didn’t send NOTIFY message to other members

- Fixed BLF&Eventlist: cannot monitor remote parking lot when outbound pattern is prefixed with ‘0_’

- Fixed BLF&Eventlist: UCM will reply incorrect expire when subscribe updates in dialog

- Fixed BLF&Eventlist: UCM will send notify to private IP address when NAT option is enabled

- Fixed BLF&Eventlist: UCM will send second refresh subscribe to private IP address when NAT option is enabled

- Fixed ZeroConfig: GXV3275 auto answer call-info preview error

- Fixed ZeroConfig: GXV3240 template doesn’t show extension board settings

- Fixed ZeroConfig: GXV3140 has error web access mode p value from UCM

- Fixed ZeroConfig: GXP2140 device missing account 2 option in custom config page

- Fixed ZeroConfig: GXP2135 template doesn’t include in model template list

- Fixed ZeroConfig: GXP1610 XML template caused CGI crash

- Fixed ZeroConfig: GXP1625 cannot auto pick extension from UCM

- Fixed ZeroConfig: GXP1600 series cannot obtain LDAP phonebook XML file from UCM

- Fixed ZeroConfig: GXP1628 upgrade method issue

- Fixed ZeroConfig: GXP2200 fail to auto assign extension after deleting the original extension

- Fixed ZeroConfig: GXP2200 preview and web access mode doesn’t match

- Fixed ZeroConfig: GAC2500 cannot auto assign and pick up extension

- Fixed ZeroConfig: DP715 NAT traversal doesn’t have UPNP option

- Fixed ZeroConfig: GSWave cannot obtain correct p value for auto answer from UCM

- Fixed ZeroConfig doesn’t display null when extension number is not set

- Fixed ZeroConfig cannot auto discover in VLAN

- Fixed ZeroConfig deleting device from zero config page will cause error prompt

- Fixed ZeroConfig disabled template still shows as active in the template list

- Fixed ZeroConfig global policy tooltips multi-language issue

- Fixed ZeroConfig global policy doesn’t display XML phone book size

- Fixed ZeroConfig global policy XML phone error prompt language display issue

- Fixed ZeroConfig global policy set to manual cannot display related configuration options

- Fixed ZeroConfig global policy allow to upload all file format as firmware

- Fixed ZeroConfig global policy allow to upload all file format as XML phone book file

- Fixed ZeroConfig global policy error prompt when deleting template

- Fixed ZeroConfig global policy has incomplete tooltips

- Fixed ZeroConfig cannot modify MPK and MPK EXT board settings

- Fixed ZeroConfig cannot redirect user to zero config page when zero config is disabled

- Fixed ZeroConfig doesn’t support concurrent registration

- Fixed ZeroConfig reboot the device on extension page caused crash

- Fixed ZeroConfig doesn’t support concurrent registration

- Fixed ZeroConfig will auto assign deleted extension to device

- Fixed ZeroConfig cannot provision devices when UCM has class B IP address

- Fixed ZeroConfig abnormal display when template name has special characters

- Fixed ZeroConfig account preview doesn’t match config file

- Fixed ZeroConfig: some IP will cause error prompt “unable to update your request”

- Fixed ZeroConfig cannot set device IP in range of 172.16.0.255 and 172.16.1.0

- Fixed ZeroConfig auto discover will fail if DHCP server has changed

- Fixed ZeroConfig auto discover cannot display class B range IP address

- Fixed ZeroConfig abnormal display when reset model template LDAP phone book to default

- Fixed ZeroConfig vulnerability about HTTP header injection

- Fixed ZeroConfig extension cannot display in device list

- Fixed ZeroConfig auto discover issue

- Fixed ZeroConfig pick up extension requires device to reboot when updating from model update page

- Fixed Voicemail: Skip Voicemail Password Authentication is still active when voicemail is disabled

- Fixed Voicemail: UCM sends email to member whose voicemail box is full

- Fixed Voicemail: reply voice message to sender through peer trunk will fail

- Fixed Voicemail: UCM will save voicemail for deleted extension

- Fixed Voicemail: status doesn’t display extension voicemail after UCM reboots

- Fixed Voicemail: email attachments invalidity issue

- Fixed LDAP QR code doesn’t contain public IP address

- Fixed LDAP cannot auto fill in extension last name when importing VCF format phonebook

- Fixed LDAP mobile, home and fax number cannot contain character “-”

- Fixed LDAP doesn’t stop sending request after timeout when LDAP sync fails

- Fixed Backup doesn’t have complete CDR information

- Fixed Backup cannot restore default extension music on hold after factory reset

- Fixed Backup cannot display file list on USB

- Fixed Backup cannot fully restore backup files

- Fixed Backup: no error prompt when trying to download backup file when external media is unplugged

- Fixed Backup: cannot restore MOH when restoring voice prompt files

- Fixed Backup: deleted IVR still existed in the backup file causing callback issue

- Fixed Backup: refreshing web UI during backup will cause UCM fails to reboot

- Fixed IVR dial ‘0’ for operator voice prompt incorrect issue

- Fixed IVR cannot record new prompt from extension issue

- Fixed IVR time out and invalid destination CDR display incorrect issue

- Fixed Conference: joining conference doesn’t hear voice prompt issue

- Fixed Conference: muted member cannot be displayed on web UI

- Fixed Conference background noise not handled correctly issue

- Fixed Conference no join tone after user is invited to conference room

- Fixed Conference busy tone is too long when user rejects the invitation

- Fixed Conference meeting time is not accurate issue

- Fixed Conference invited member bridging local MCB will fail

- Fixed Conference playing MOH music when invited member holds the conference

- Fixed Conference MOH can be initiated from any joined users

- Fixed Conference DTMF inband password doesn’t work for remote conference room

- Fixed Conference admin privilege user can clean up conference schedule

- Fixed Conference mute all option can mute other administrators in the same conference room

- Fixed Conference doesn’t play hold music issue when single member in the conference room

- Fixed Conference admin press ‘*’ doesn’t play correct prompt

- Fixed Conference members who are invited from web UI into the conference room cannot use conference menu

- Fixed Conference: incorrect first name in the email when receiving invitation at remote side for scheduled conference

- Fixed Conference SIP subscription is not cleared when an invited user rejects the call

- Fixed Conference choppy voice when both PCMU and G722 codec are used in conference room

- Fixed Conference: recording is always activated even auto recording options is disabled

- Fixed Conference: admin cannot hear voice prompt when entering conference room as first person

- Fixed Conference: web UI doesn’t update status when members are mute / unmute by admin using 83

- Fixed Conference: web UI doesn’t update status when admin lock / unlock conference room

- Fixed Conference schedule can still add MCB when scheduled conference has reached maximum capacity

- Fixed Conference scheduled cannot count invited members properly when they are not available

- Fixed Conference schedule doesn’t sort the local extension

- Fixed Conference schedule error prompt when scheduling conference time

- Fixed Conference schedule email invitation has password when password is not required

- Fixed Conference CCM: invited user cannot use CCM menu when “Enable User Invite” is enabled

- Fixed Conference CCM: lock / unlock conference using CCM / web UI doesn’t play voice prompt

- Fixed Conference CEI: GXP user fails to display conference info when more than 24 members are in the conference room

- Fixed Conference CEI memory leak issue when members join the conference and subscribe CEI

- Fixed Conference CEI notify doesn’t carry invite status when “Enable User Invite” is enabled

- Fixed Conference CEI count error after MCB is created or kicked

- Fixed Conference CEI MCB cannot display remote user

- Fixed Conference CEI cannot show remote conference after MCB via SIP register trunk

- Fixed Conference CEI doesn’t take effect when UCM restarts

- Fixed Conference CEI doesn’t update mute / unmute status

- Fixed Conference CEI user subscription doesn’t clear up after being kicked out of the conference room

- Fixed Conference CEI: customized caller ID will cause conference CEI display abnormal

- Fixed Conference CEI: UCM will crash when user kicks MCB which has unsuccessful CEI re-subscription

- Fixed Conference CEI: UCM doesn’t send notify to member who is kicked by using feature code */8/2

- Fixed Conference CEI: abnormal encode header in NOTIFY message when more than 19 members join local conference and subscribe CEI

- Fixed Conference CEI: when more than 32 members join and leave conference with CEI enabled will cause UCM system crash

- Fixed SLA will have miss call record when inbound call to SLA station

- Fixed PBX Status display issue when ring group members are no longer available

- Fixed PBX Status call queue member display issue

- Fixed PBX Status CGI disconnect and abnormal display

- Fixed PBX LDAP server web UI Spanish display issue

- Fixed PBX office/holiday web page language prompt error

- Fixed PBX FXS status display error

- Fixed SPY Whisper mode abnormal behavior when trying to monitor idle extension

- Fixed SPY plays error extension number when monitoring FXS extension

- Fixed SPY: call barging display issue when monitoring external number

- Fixed SPY: monitoring invalid extension doesn’t have error prompt

- Fixed SPY: voice prompt is incorrect when using feature code to monitor FXS extension

- Fixed SPY: monitored extension set to unconditional forward will cause web UI display two identical calls in active call page

- Fixed Follow me: using feature code *80 / *81 to call follow me members will cause web UI display two identical calls in active call page

- Fixed Follow me: voice prompt error when default destination is IVR

- Fixed Troubleshooting capture filter can have special characters

- Fixed voice prompt doesn’t match web UI language selection

- Fixed WebRTC smart route enable destination option to gray

- Fixed WebRTC: special characters in the TURN server password will cause prompt fail to update data

- Fixed WebRTC: tooltips issue for “Max bandwidth” option in Chinese

- Fixed Google service will stop working when restore backup file

- Fixed Fax file name multi-language display issue

- Fixed Paging Intercom tool tips typo

- Fixed Paging Intercom feature code *81 doesn’t work issue

- Fixed Paging Intercom cannot display caller ID name issue

- Fixed Paging Intercom abnormal behavior after reset user data when Paging Intercom has customized prompt

- Fixed Ring Group cannot modify extension number when ring group voice mail is enabled

- Fixed Ring Group ring in order issue when there are remote members in the ring group

- Fixed Ring Group call will drop in 20 seconds when the call is transferred to extension’s voicemail

- Fixed Upgrade: upgrade has a low chance will fail when upgrade to latest firmware

- Fixed Fax / T.38 has incorrect tooltips

- Fixed Fax / T.38 doesn’t work correctly on SIP trunk

- Fixed System Event: alert contacts can apply same email address when change different web UI language

- Fixed System Event: incorrect alert for “SIP Outgoing Call Through” prompt

- Fixed System Event will generate SIP Lost Registration alert to unregistered extension

- Fixed System Event doesn’t generate SIP fail warning when registration failed

- Fixed System Event warning email notification can be enabled when email address is not set

- Fixed System Event Disk Usage alert only detects data partition

- Fixed System Crash caused by no SDP content in SIP INVITE header

- Fixed System is vulnerable to XSS attack

- Fixed System: DNS query caused system crash

- Fixed DISA: call completion mode will cause user fail to use DISA

- Fixed DISA call will enter voicemail when DISA call is being transferred and hung up

- Fixed AMI: originating a call from AMI interface cannot leave a voicemail when callee rejects the call

- Fixed Operation log: IVR key event language display abnormal

- Fixed Operation log: super admin login to UCM doesn’t generate operation log

- Fixed Operation log: some operations don’t have page detail in operation log

- Fixed Operation log tooltips unclear issue

- Fixed Operation log: IP address doesn’t have valid format restriction

- Fixed Setup Wizard register trunk with cannot be saved with some specific settings

- Fixed NAT: UCM IP NAT update issue

- Fixed SIP option request is rejected with 403 response

- Updated bundle of CA root certificates

IMPORTANT UPGRADING NOTE:

- Backup, Backup, Backup, yes, backup your data (including configuration) before doing any firmware upgrade! (An SD card or USB Flash Drive is needed for backup purpose.)

- Upgrading from firmware version 1.0.9.26 (or lower) to firmware version 1.0.11.27 directly is not supported. Please upgrade to 1.0.9.97 and then 1.0.10.44 (in the firmware package), before upgrading to 1.0.11.27. The firmware upgrading process should be 1.0.9.26 (or lower) -> 1.0.9.97 -> 1.0.10.44 -> 1.0.11.27.

- Will be reset to factory default settings after upgrading to 1.0.11.27. Users need to restore backup file manually or re-configure after upgrade. Therefore, it is VERY IMPORTANT to manually BACKUP data on the UCM61xx before upgrade. Users will also be requested for backup when upgrading from 1.0.9.97 to 1.0.10.44.

- Once upgraded to 1.0.11.27, downgrading to 1.0.9.26 (or lower) is not supported.

UPGRADING INSTRUCTIONS:

- Upgrade UCM61xx from firmware 1.0.9.26 to 1.0.9.97 using the 1.0.9.97 “ucm6100fw.bin” file.

- When the UCM61xx is on firmware 1.0.9.97, open a web browser on a PC connected to the same network as UCM61xx to log in UCM61xx web UI. Go to Maintenance->Upgrade page, manually upload “ucm6100dpt.bin” file under Local Upgrade section from your PC.

- Once the UCM61xx finishes loading the ucm6100dpt.bin file successfully, it will reboot and automatically boot into recovery mode.

- In recovery mode, the UCM61xx LCD will display its IP address. Please type this IP address in the web browser of your PC that is connected to the same network as the UCM61xx. Please make sure you have cleared your browser cache and type in IP address only (Do not specify protocol or port number).

- For example, if the IP address displayed in LCD is 192.168.1.2, please type in 192.168.1.2 in the browser address bar.

- Log in the UCM61xx as administrator.

- Once logged in, click on “Upload” and select firmware 1.0.10.39 “ucm6100fw.bin” file from your PC to upload.

- Please keep the web page open and wait until uploading is finished. Once done, an upgrading successful message will be prompted.

- On the recovery mode web UI, select “Reboot” to reboot the UCM61xx.

- Your UCM61xx is successfully upgraded to 1.0.10.39.

About VoIP System Updates:

Firmware updates for VoIP Systems are very complex and usually contain many bug fixes, security improvements and compatibility enhancements, because the base system must be able to connect to webcams, video conference devices and the like.

Upgrading your VoIP System firmware should be done as often as possible to keep your device up to date with new security standards, and improve the native plug and play capabilities of your device.

Although beta firmware are usually full of new and exciting features, updating to them should only be done after thoroughly reading the changelog and making sure that you still retain phone functionality. Remember to check if you can revert to a more stable version as well, in case the new update is not what you were expecting.

If you intend to apply this update, please make sure that the package is compatible with your VoIP System, hit the download button, follow the installation instructions and enjoy. Check out our website as often as possible in order to keep your device “Updated one minute ago.” 

It is highly recommended to always use the most recent driver version available

Do not forget to check with our site as often as possible in order to stay updated on the latest drivers, software and games

Try to set a system restore point before installing a device driver

This will help if you installed a wrong driver

Problems can arise when your hardware device is too old or not supported any longer