© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateway Enterprise Deployments Introducing IP-to-IP Gateways

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateway Functionality IP-to-IP gateway interconnects VoIP networks Also called session border controller Implemented on Cisco IOS gateways using special Cisco IOS release Ability to connect one VoIP dial peer with another VoIP dial peer Powerful protocol interworking tool set: –H.323-to-SIP –H.323-to-H.323 –SIP-to-SIP

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateway Functionality (Cont.) SIP or H.323 IP-to-IP Gateway Inbound VoIP Dial Peer Outbound VoIP Dial Peer IP-to-IP gateway connects VoIP dial peers.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Cisco IOS Image Support for IP-to-IP Gateways IP-to-IP gateway functionality supported on most current platforms including Cisco 2800 and 3800 Series ISR Introduced with Cisco IOS Release 12.2(13)T Requires one of these IOS feature sets: –INT VOICE/VIDEO, IPIPGW, TDMIP GW AES –INT VOICE/VIDEO, IPIPGW, TDMIP GW

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateways in Enterprise Environments External connections: –Interconnect with VoIP carriers –Interconnect with other voice and video networks –Integrate Internet VoIP and video over IP users Internal connections: –Increase interoperability within a VoIP network Relevant features: –Protocol interworking –Address hiding –Security –Video integration –CAC

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateways in Enterprise Environments (Cont.) LAN/WAN IPIPGW Internet SIP Carrier H.323 Video GK Cisco Unified CallManager H.323 Video Video interworking for external video clients CAC between Cisco Unified CallManager Interworking and CAC between Cisco Unified CallManager Express and Cisco Unified CallManager Protocol interworking Secure VoIP interworking GK=Gatekeeper IPIPGW=IP-to-IP Gateway

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Protocol Interworking on IP-to-IP Gateways Solves interoperability issues when using the same signaling protocol Translates between signaling protocols: –Each call leg terminates on the IP-to-IP gateway. –The IP-to-IP gateway examines received information, performs translation, and reoriginates a new call leg.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Protocol Interworking on IP-to-IP Gateways (Cont.) In LegOut LegSupport Fast Start Bidirectional Slow Start Bidirectional Fast StartSlow StartBidirectional H.323-to-H.323 H.323-to-SIP SIP-to-SIP In LegOut LegSupport Fast StartEarly OfferBidirectional Slow StartDelayed OfferUnidirectional In LegOut LegSupport Early Offer Bidirectional Delayed Offer Bidirectional

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Media Flows with IP-to-IP Gateways IP-to-IP gateway proxies H.323 and SIP (proxy signaling) Media flow-through (default): All media streams are routed through the IP-to-IP gateway –Solves IP interworking issues –Hides IP original addresses –Enables tighter security policies Media flow-around: Media streams flow directly between endpoints.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Media Flows with IP-to-IP Gateways (Cont.) Cisco Unified CallManager Cluster 2 Cisco Unified CallManager Cluster 1 IP-to-IP Gateway Phone Phone Media flow-through: Signaling

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Media Flows with IP-to-IP Gateways (Cont.) Phone Phone Media flow-around: Signaling Cisco Unified CallManager Cluster 2 Cisco Unified CallManager Cluster 1 IP-to-IP Gateway

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Codec Filtering on IP-to-IP Gateways VoIP networks support multiple codecs: –Define which codec is preferred over another IP-to-IP gateways can limit codec negotiation down to a single codec: –Ensures that a specific codec is negotiated –Simplifies design considerations IP-to-IP gateways also support transparent codec negotiations: –Transparently passes codec capabilities between endpoints Implemented via dial peer configuration

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Codec Filtering on IP-to-IP Gateways (Cont.) VoIP 1VoIP G.711alaw 2. 2.G.729a 3. 3.G.729b 1. 1.G.711alaw 2. 2.G.729a 3. 3.G.729b 1. 1.G.729a VoIP 1VoIP G.711alaw 2. 2.G.729a 3. 3.G.729b 1. 1.G.711alaw 2. 2.G.729a 3. 3.G.729b Transparent IP-to-IP Gateway IP-to-IP gateway codec negotiation: IP-to-IP gateway with codec transparency

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v RSVP-Based CAC on IP-to-IP Gateways IP-to-IP gateways can use standard Cisco IOS gateway RSVP call support. Enables RSVP-based CAC: –Cisco Unified CallManager intercluster RSVP-based CAC –Support for voice and video calls Requirements: –Two IP-to-IP gateways used as RSVP peers –Media-flow through to ensure that the reserved path is used

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v RSVP-Based CAC on IP-to-IP Gateways (Cont.) IP-to-IP Gateway IP WAN Cisco Unified CallManager Cluster 2 Cisco Unified CallManager Cluster 1 IP-to-IP Gateway H.225 Setup RSVP Reservation H.225 Setup H.245 Setup H.245 Setup with Media Flow-Through Call Established H.225 Setup

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateways and Gatekeeper Interworking IP-to-IP gateways can register with a gatekeeper like any other Cisco IOS gateway: –The gatekeeper and IP-to-IP gateway may be deployed on the same router. IP-to-IP gateways can also be used by gatekeepers using via- zones: –A via-zone is a Cisco term for a zone that contains IP-to-IP gateways and via-zone-enabled gatekeepers. –The via-zone-enabled gatekeeper is capable of recognizing via-zones and sending traffic to via-zone gateways. –Via-zones are usually located on the edge of an enterprise or Internet telephony service provide network, and are like a VoIP transfer point, or tandem zone, where traffic passes through on the way to the remote zone destination.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateways and Gatekeeper Interworking (Cont.) VIA zone IP-to-IP Gateway VIA GK 408 zone SJC GK SJC Cisco Unified CallManager 857 zone BOS GK BOS Cisco Unified CallManager SIP Carrier Via-zone used to route between zones over an IP-to-IP gateway Standard H.225 RAS to route call to other VoIP networks using an IP-to-IP gateway GK=Gatekeeper

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateway Call Flows Cisco Unified CallManager – IP-to-IP Gateway – Cisco Unified CallManager Express Cisco Unified CallManager – IP-to-IP Gateway with RSVP – Cisco Unified CallManager Cisco Unified CallManager – IP-to-IP Gateway – SIP Carrier Cisco Unified CallManager – Gatekeeper – IP-to-IP Gateway – SIP Carrier Cisco Unified CallManager – Via-zone Gatekeeper – IP-to-IP Gateway – Cisco Unified CallManager

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateway Call Flows: Cisco Unified CallManager to Cisco Unified CallManager Express IPIPGW Cisco Unified CallManager Express 1 H.225, H.245 no H.450 Cisco Unified CallManager 2 H.225, H.245 with H.450 Phone Phone Phone Phone1-1 calls Phone2-1. Phone2-1 transfers call to Phone3-1. Call is transferred without hairpinning 2 3 GK=Gatekeeper IPIPGW=IP-to-IP Gateway

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateway Call Flows: Cisco Unified CallManager to Cisco Unified CallManager IPIPGW Cisco Unified CallManager H.225 and H.245 SCCP RTP IPIPGW Cisco Unified CallManager H.225 and H.245 H.225 and H.245 RSVP RTP IPIPGW=IP-to-IP Gateway

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateway Call Flows: SIP Carrier Interworking IPIPGW Cisco Unified CallManager H.225 and H.245 SCCP RTP SIP Carrier RTP

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v IP-to-IP Gateway Call Flows: Gatekeeper and SIP Carrier Interworking ITSP zone IPIPGWITSP GK 408 zone SJC GK SJC Cisco Unified CallManager SIP Carrier H.225 RAS H.225 and H.245 SIP GK=Gatekeeper IPIPGW=IP-to-IP Gateway

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v VIA zone IP-to-IP Gateway Call Flows: IP-to-IP Gateways and Via-Zone Gatekeepers IPIPGWVIA GK 408 zone SJC GK 857 zone BOS GK 1, 2, 5 3, 410, , 8, 9, , 15 GK=Gatekeeper IPIPGW=IP-to-IP Gateway BOS Cisco Unified CallManager SJC Cisco Unified CallManager

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Summary IP-to-IP gateways interconnect multiple VoIP networks by routing calls between two VoIP dial peers. Features include protocol interworking, address hiding, codec filtering, and video interworking. Protocol interworking interconnects VoIP networks, using the same or different signaling protocols. Media streams can flow through or bypass an IP-to-IP gateway. IP-to-IP gateways use standard Cisco IOS codec negotiations to influence negotiations between VoIP networks. IP-to-IP gateways can use RSVP to implement CAC; for example, between Cisco Unified CallManager clusters. IP-to-IP gateways can register with gatekeepers and be used as a standard gateway or with via-zones.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v