-
transcoding, bearing switching and media control-H323
connection (barrer) control plane
-
for switching logic control plain what is the connection protocols
MGCP and SGCP
-
signaling and call control, end to end voice services
call control plane
-
IN Service Logic, AAA, Address resolution
service plane
-
route voice and data calls between the PSTN and packet networks.
Cisco PGW2200
-
Since it take advantage of SS7 what are the control protocls that it takes advantage of
MGCP, H.323, SIP
-
is a carrier-class call agent that performs the signaling and call control tasks(such as digit analysis, routing, circuit selection, and more) within the PSTN gateway infrastructure.
Cisco PGW2200
-
PGW interconnect carrier class voip to pstn, name some other devices that it can talk to
Media GW, H.323 client
-
a switch thats hardare that is not dedicated
softswitch
-
whats must is a carier requirement to move from PSTN to IP
- the signaling must move
- (SS7 and ISDN dont work)
-
what is not suitable with PSTN signaling
TCP
-
which a lost packet causes undue delay of delivery of subsequent packets to the application.
head of line blocking
-
what is needed for PSTN latency requirements
message delimiter and push operations
-
what is vunerable to DoS attacks
TCP
-
who made SCTP
SIGTRAN IETF
-
what protocol is an extension of SS7
SIGTRAN
-
but uses an Internet Protocol (IP) transport called Stream Control Transmission Protocol
SIGTRAN
-
is used to carry PSTN signaling over IP
SCTP
-
Message orientated
error free data transfer
out of order delivery
piggybacking
multihomin
SCTP
-
in which multiple user messages can be bundled and sent as one SCTP packet across the network. This provides efficiency
Piggybacking
-
by introducing the concept of an association between endpoints.
multihoming
-
can provide its peer with a list of transport addresses (multiple IP addresses) through which it can be
reached and from which it originates packets.
SCTP endpoint
-
resistance to some DoS attacks
SCTP
-
control for in band signaling
IUA
-
The ISDN signaling information needs to be transported (also known as backhaul) to the WHAT?? for call processing
MGC
-
the GW terminates Q.921 and backhauls Q.931 to
MGC
-
IUA supports what boundary primitives
Q.921/Q.931
-
to help Layer Management modules manage the SCTP association(s) between the
SG and MGC
-
SG maintains the availability and active/inactive state of all
ASP
-
box can resolve vendor incompatibility by designing and development interworking functions (IWF)
Session Border Control (SBC)
-
Designed for VOIP peering of two or more networks
Session Border Controller (SBC)
-
SBCs are conceived with the following interworking functions (IWF)
- IP address and port translations
- Billing and CDR normalization
- VoIP security (NAT traversal, LI,Authentication, and so on)
- Media interworking to resolve codec,DTMF-RELAY, and FAX issues
- QoS and bandwidth management
- Rich signaling and application interworking
- Consistency with VoIP protocols
-
Where you can find SBC fuctionality
- Standalone SBC
- Routing devices
- Media gateways
- Security devices
-
what type of applications are these
business voice services and features
site-to-site voice calls over IP networks
Public Switched Telephone network (PSTN) access
unified messaging
advanced IP services such as instant messaging and presence-enabled networks
Enterprise Voice over IP (VoIP)
-
Enterprise applications must be ran on what
regular phone, a soft phone running on a pc or a cell phone.
-
taking off it off the PSTN you save on long-distance charges by using extra bandwidth on their data network without losing existing functionality.
Toll bypass
-
where is toll bypass used
between their intraoffice (branch and HQ)
-
by putting a softphone on a pc can increase what
delay
-
enables businesses to put a link on their websites that automatically places a call from a customer service representative to a customer.
Click 2 call
-
provides integration between traditional phone services with application sharing and H.323-based video conferencing.
Microsoft netmeeting
-
provides the look and feel of a traditional handset, with the added functionality of IP connectivity.
Cisco IP Phone
-
extends the handset functionality onto the PC with a graphical user interface that provides the same functionality as the handset and integrates with other multiservice applications such as web browsing, Microsoft Netmeeting, or directory services based on Lightweight Directory Access Protocol (LDAP).
Cisco PC based Soft Phone
-
using these drive what
video communication
collaboration tools
presence-aware services
Wi-Fi-enabled phones
Better voice quality using wideband codecs
driving productivity
-
proving more relalistic sound quality
Wideband Codecs
-
Instead of 4 kHz sampling, use 16 kHz sampling
This allows transmissions offrequencies up to 8 kHz without high network demand
Wideband Codecs
-
is a wideband codec defined by ITU.
G722.2
-
is an adaptive multirate codec with a bit rate between 6 and 23.85 kbps.
G722.2
-
from Global IP Sound is another wideband codec with a variable transmission rate between 10 and 32 kbps.
also robust against packet loss.
iSAC
|
|