Cisco Expressway Series, Configuration Manual

Page: 17 / 47

Purpose Src. IP Src. ports Protocol Dest. IP Dst. Ports
Assent RTCP
(traversed
media)
SIP endpoint
(or its
firewall)
>=1024
Could be translated by
the firewall to port where
the media egressed,
rather than an endpoint
port
UDP Expressway-
E 36000-59999
Assent RTP
(traversed
media)
Expressway-
E 36000-59999 UDP SIP endpoint
(or its
firewall)
>=1024
Expressway waits until it
receives media, then sends
media to that source port
(which could be the port where
the media egressed the firewall,
not an endpoint port)
TURN control Any
IP address
†
>=1024 (signaling port
from endpoint or the
firewall) UDP
& TCP Expressway-
E
3478 (Small/Medium)
3478-3483 (Large)
TURN media
Expressway-
E 24000-29999 UDP
& TCP
Any
IP address >=1024
TURN media Any
IP address
‡
>=1024
Port of relevant
ICE candidate: host
IP port, server reflexive
port (outside firewall
port), or TURN server
port
UDP
& TCP Expressway-
E 24000-29999
Table 9 SIP Calls Port Reference (continued)
† The request could be from any IP address, unknown to the TURN server. Assume for example, that endpoint A and
endpoint C (TURN clients) in the diagram can use the Expressway-E TURN server. The actual IP address from which
the TURN server receives the request could be the endpoint's firewall egress address (NATed).
‡ The media could go to any of the candidate addresses. For example, before ICE negotiation the TURN server does
not know which of endpoint B's candidate addresses will be the highest priority.
Note: The endpoints A, B, and C in the diagram only show media connections to avoid unnecessary lines. They would
use the same signaling connections as shown for the other endpoints / bridges.
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Cisco Expressway IP Port Usage Configuration Guide