Product specifications

Dialogic® BorderNet™ 4000 SBC Product Description Document
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9. Media Handling
The BorderNet 4000 SBC provides media termination and relay to handle RTP traffic from
remote entities signaled through SIP/H.323 messages. It also determines the appropriate
media path for a session based on configured options and supports:
• RTP/RTCP, T.38
• Dynamic pin-holing based on SDP
• Rate limits per media flow
Signaling and Media Separation
The BorderNet 4000 SBC can be configured to terminate the signaling and the media, or it
can be configured to terminate just the signaling. The IP network topology must enable
direct IP routing for media between the two endpoints.
Media Latching
The BorderNet 4000 SBC restricts latching RTP/RTCP media for all calls within the context of
a peer or SIP interface. The destination address and port for subsequent RTP packets is
determined from the SDP. Media latching can be configured by the operator.
Media Over Multiple Physical Interfaces
From a single signaling IP address, the BorderNet 4000 SBC can split media over different
physical interfaces with different media IP addresses.
Media Rate Limiting
The BorderNet 4000 SBC ensures that media streams associated with a particular session
use the appropriate codec (bandwidth) based on the SDP information in the SIP message.
Topology Hiding for Media
The BorderNet 4000 SBC provides topology hiding for the trusted network infrastructure
from untrusted networks. This is accomplished by implementing Network Address and Port
Translations (NAPT) for media sessions (RTP and RTCP) passing through the BorderNet
4000 SBC. For example, in the following diagram, the remote end points (or gateways) on
the public side see only the public IP address (212.179.134.99) and not the core network
address (192.168.0.1).