Cisco IOS Release 12.1X

• Caller ID on 2600, 3600 and MC3810

• Cisco H.235 Accounting and Security Enhancements for Cisco Gateways

• Cisco H.323 Multizone Enhancements

• Cisco High-Performance Gatekeeper

• Configuring an ISDN BRI NT/TE Interface on Voice Interface Cards and ISDN BRI Voice Modules

• FXO Disconnect Supervision

• H.323 Call Redirection Enhancements

• Interworking Signaling Enhancements for H.323 and SIP VoIP

• Voice over ATM with AAL2 Trunking on Cisco MC3810-V3 Series Concentrators