AudioCodes Mediant 500 MSBR, User Manual

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User's Manual 430 Document #: LTRT-10375
Mediant 500 MSBR
Parameter Description
addresses.

[2] Prefer IPv4 = SDP offer includes IPv4 and IPv6 media IP
addresses, but the first (preferred) media is IPv4.

[3] Prefer IPv6 = SDP offer includes IPv4 and IPv6 media IP
addresses, but the first (preferred) media is IPv6.
To indicate ANAT support, the device uses the SIP Allow header
or to enforce ANAT it uses the Require header:
Require: sdp-anat
In the outgoing SDP, each 'm=' field is associated with an ANAT
group. This is done using the 'a=mid:' and 'a=group:ANAT'
fields. Each 'm=' field appears under a unique 'a=mid:' number,
for example:
a=mid:1
m=audio 63288 RTP/AVP 0 8 18 101
c=IN IP6 3000::290:8fff:fe40:3e21
The 'a=group:ANAT' field shows the 'm=' fields belonging to it,
using the number of the 'a=mid:' field. In addition, the ANAT
group with the preferred 'm=' fields appears first. For example,
the preferred group includes 'm=' fields under 'a=mid:1' and
'a=mid3':
a=group:ANAT 1 3
a=group:ANAT 2 4
If you configure the parameter to a "prefer" option, the outgoing
SDP offer contains two medias which are the same except for
the "c=" field. The first media is the preferred address type (and
this type is also on the session level "c=" field), while the second
media has its "c=" field with the other address type. Both medias
are grouped by ANAT. For example, if the incoming SDP
contains two medias, one secured and the other non-secured,
the device sends the outgoing SDP with four medias:

Two secured medias grouped in the first ANAT group, one
with IPv4 and the other with IPv6. The first is the preferred
type.

Two non-secured medias grouped in the second ANAT
group, one with IPv4 and the other with IPv6. The first is the
preferred type.
Note:

The parameter is applicable only when the device offers an
SDP.

The IP addressing version is determined according to the first
SDP "m=" field.

The feature is applicable to any type of media (e.g., audio
and video) that has an IP address.

The corresponding global parameter is
MediaIPVersionPreference.
RTP Redundancy Depth
rtp-redundancy-depth
[IpProfile_RTPRedundancyDepth
]
Enables the device to generate RFC 2198 redundant packets.
This can be used for packet loss where the missing information
(audio) can be reconstructed at the receiver's end from the
redundant data that arrives in subsequent packets. This is
required, for example, in wireless networks where a high
percentage (up to 50%) of packet loss can be experienced.

[0] 0 = (Default) Disable.