Cisco Systems ASR 1000 manual Integrated SBC Used for VoIP Interworking

Chapter 1 Integrated Session Border Controller for the Cisco ASR 1000 Series Routers Overview

Integrated Session Border Controller DBE Deployment Scenario

This scenario requires the SP to provide capabilities such as opening pinholes for the duration of a conversation, and doing this without exposing the devices behind the firewall to malicious threats. In addition, given that voice is extremely sensitive to issues such as delay, latency, and packet loss, ensuring adequate performance is a challenge. QoS mechanisms can be implemented to ensure proper priority is assigned to voice packets.

In this deployment scenario, multiple applications share a common link. Thus a mechanism that will limit bandwidth available to individual applications to ensure appropriate end-to-end quality is needed. For voice, this would involve correctly marking the packet to ensure appropriate priority, as well as controlling the number of simultaneous calls at the network entry point. Because the SP cannot dictate what IP phones their customers use, protocol conversion functionality is needed—especially H.323-to-SIP conversion.

Service providers require measurement of traffic for reporting and billing purposes in this potential scenario. Some carriers may also want to offer service level agreement (SLA) for voice, for which they want to be able to provide their customers with the proof that these SLAs are being met.

Figure 1-4 on page 1-9illustrates a deployment where Integrated SBC is used for VoIP interworking.

Figure 1-4 Integrated SBC Used for VoIP Interworking

SP3			SBC	SP2
				IP/MPLS
PSTN		SBC
				Network
SBC	SBC
Data		SP1
		IP/MPLS Network
Center
		SBC
	SBC	SBC

SBC

M

MM

MM

IP IP IP

Managed Enterprise

SBC

M

MM

MM

IP	IP	IP
		271025

Unmanaged Enterprise

Residential Broadband

Cisco IOS XE Integrated Session Border Controller Configuration Guide for the Cisco ASR 1000 Series Aggregation Services Routers

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