Cisco Cisco Packet Data Interworking Function (PDIF) Guía Para Resolver Problemas
Session Control Manager Overview
Features and Functionality - Base Software ▀
Cisco ASR 5000 Series Session Control Manager Administration Guide ▄
OL-22952-01
As the logical anchor point within the packet core, the SCM improves the user experience with device and location
independence, and enhances subscriber control and policy enforcement with faster, more intelligent decisions for
multimedia services.
independence, and enhances subscriber control and policy enforcement with faster, more intelligent decisions for
multimedia services.
Furthermore, as Fixed Mobile Convergence takes hold, it will be especially important to incorporate the SCM in the
packet core in order to achieve mobility and voice continuity between multiple access networks (3G, WiFi, WiMAX,
etc.).
packet core in order to achieve mobility and voice continuity between multiple access networks (3G, WiFi, WiMAX,
etc.).
Figure 6.
Cisco Integrated Session Control Manager
In te g ra te d
S e ssio n C o n tro l M a n a g e r
S T 4 0
S IP
B e a re r
S IP -A S
S IP -A S
S IP -A S
IM S P a cke t
N e tw o rk
U M T S /W C D M A
IP A c c e s s
N e tw o rk
M M D P a cke t
N e tw o rk
C D M A 2 0 0 0
N e xt G e n .
P a cke t N W
F u tu re :
W iF i, W iM A X
SIP Large Message Support
Large notify contains information about multiple users in one message, which reduces the number of SIP messages in
the network. Large SIP messages can be sent on UDP if the endpoint can support fragmentation; otherwise, UDP to
TCP switching can be used to transport large messages intact.
the network. Large SIP messages can be sent on UDP if the endpoint can support fragmentation; otherwise, UDP to
TCP switching can be used to transport large messages intact.
If a request is within 200 bytes of the path MTU, or if it is larger than 1300 bytes and the path MTU is unknown, the
request MUST be sent using TCP. This prevents fragmentation of messages over UDP and provides congestion control
for larger messages. P-CSCF/A-BG is also able to handle messages up to the maximum datagram packet size. For UDP,
this size is 65,535 bytes, including IP and UDP headers.
request MUST be sent using TCP. This prevents fragmentation of messages over UDP and provides congestion control
for larger messages. P-CSCF/A-BG is also able to handle messages up to the maximum datagram packet size. For UDP,
this size is 65,535 bytes, including IP and UDP headers.
Large message support is needed for handling presence signaling traffic as the size of messages could be as large as
50K.
50K.
SIP Routing Engine
The SIP routing engine deploys SIP in a secure and controlled fashion.
Provides auto discovery of SIP elements, subscriber privacy, call fraud prevention, network security, and thwarting of
network overload conditions.
network overload conditions.