# Technical References

- [SIP Trunk Requirements: Ports, Protocols, and Codecs](/support/services/voice-over-ip-voip/technical-references/sip-trunk-requirements-ports-protocols-and-codecs.md): This article outlines the essential requirements for SIP trunks
- [How much bandwidth do I need for VoIP?](/support/services/voice-over-ip-voip/technical-references/how-much-bandwidth-do-i-need-for-voip.md)
- [Grandstream Device Management System (GDMS)](/support/services/voice-over-ip-voip/technical-references/grandstream-management-portal.md)
- [How to login to the GDMS platform](/support/services/voice-over-ip-voip/technical-references/grandstream-management-portal/how-to-login-to-the-gdms-platform.md): This is article covers how to log in using your GDMS account
- [How to run diagnostic tests within the GDMS](/support/services/voice-over-ip-voip/technical-references/grandstream-management-portal/how-to-run-diagnostics-on-phone-in-gdms.md): This article runs through some of the diagnostic capabilities of the Grandstream Device Management System and how to access them.
- [How to add a site and move a VoIP Device into it](/support/services/voice-over-ip-voip/technical-references/grandstream-management-portal/how-to-add-a-site-and-move-a-phone-into-it.md): This article goes over how you can add a site to the GDMS platform and move a VoIP device into it, essentially associating it with a customer
- [How do I add/remove users from the GDMS Portal?](/support/services/voice-over-ip-voip/technical-references/grandstream-management-portal/how-to-get-a-new-user-added-to-the-portal.md): This article covers how partners can give additional users access to the GDMS to manage the phones and carry out troubleshooting
- [Best Practice Guidelines](/support/services/voice-over-ip-voip/technical-references/best-practice-guidlines.md): Guidelines on how to improve the uptime/stability of their services by implementing redundant links and failover options.
- [Best Practices to Protect You from Toll Fraud](/support/services/voice-over-ip-voip/technical-references/best-practices-to-protect-you-from-toll-fraud.md): This page provides information on how to prevent toll fraud
- [Brand Specific Guides](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides.md): This section contains guides and information for the various SIP Phone brands.
- [NetComm Router/ATA](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides/netcomm-router-ata.md)
- [How to register VOIPnow extension to NetComm device (NL1901ACV)](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides/netcomm-router-ata/how-to-register-voipnow-extension-to-netcomm-device-nl1901acv.md): This article covers how to configure NetComm devices
- [Cisco](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides/cisco.md)
- [SPA112 - Fax Settings](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides/cisco/spa112-fax-settings.md)
- [Grandstream](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides/grandstream-handsets.md): Hosted Network supply Grandstream handsets with our VoIP Bundles, you may find the following manuals useful.
- [How to enable TLS encryption on Grandstream phone](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides/grandstream-handsets/how-to-enable-tls-encryption-on-grandstream-phone.md): This article covers how to configure TLS on your Grandstream Phones
- [Upgrading the firmware on Grandsteam phones](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides/grandstream-handsets/upgrading-the-firmware-on-grandsteam-phones.md)
- [Setting up voicemail on the DP720 (Cordless Handset)](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides/grandstream-handsets/setting-up-voicemail-on-the-dp720-cordless-handset.md): This article covers the setup of voicemail on the DP720 cordless handset.
- [How to setup a VoIP Account on a Grandstream phone](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides/grandstream-handsets/how-to-setup-a-voip-account-on-a-grandstream-phone.md): A guide on how to setup a Hosted Network VoIP Extension on a Grandstream phone.
- [Grandstream GXP2140 Voicemail](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides/grandstream-handsets/grandstream-gxp2140-voicemail.md)
- [Setting up Monitored Call Parking](/support/services/voice-over-ip-voip/technical-references/brand-specific-guides/grandstream-handsets/setting-up-monitored-call-parking.md)
- [Managing Call Diversions for DID Numbers (AudioCodes SIP Trunks)](/support/services/voice-over-ip-voip/technical-references/managing-call-diversions-for-did-numbers-audiocodes-sip-trunks.md)