Gateway and Trunk Concepts Chapter 07
The Process of Converting Voice to Packet 0
Encoding Voice into Binary mu-law is a positive value is a negative value
Choosing a Voice Codec
prod_qas0900aecd8016c6ad_ps3115_Products_Q_and_A_Item.html
RTP and RTCP – Real-time Transport Protocol Sequence numbers Time stamps Real-time Transport Control Protocol – Packet count – Packet delay – Packet loss – Jitter (delay variations)
Trunking CME to the PSTN
Trunking CME to Other VoIP Systems
H.323 The first VoIP
SIP Session Initation Protocol – NEXT Generation of H.323
MGCP Media Gateway Control Protocol – First true client/server VoIP signaling protocol “Call agent” – Not as widely supported as H.323 or SIP
SCCP Skinny Client Control Protocol – Only Cisco proprietary protocol in use today – Its function is to provide signaling between the Cisco Unified Communication Manager and the Cisco IP phones
ITSP (Internet Telephony Service Providers) Vonage Verizon at&t Ooma
VoIP ISP in USA (sample list) Best X-Voice Magic Jack Nextiva Avaya Lingo Zimbio NEC Ooma 8x8 Talk Switch Cisco ShoreTel Intalk Viatalk VoIP.com ITP Vonage
Configuring and Verifying Gateway and Trunk Chapter 08
Configuring Analog Ports FXS FXO
FXS Foreign Exchange Station Ports Signaling types – Ground start – Loop start
FXO Foreign Exchange Office
Configuring Digital Voice Ports T1 CAS PSTN interfaces T1 CCS PSTN interfaces PBXs use E&M CAS typically uses loop start
Configuring a T1 CAS PSTN Interface Turn to page 253
Configuring a T1 CCS PSTN Interface Turn to page 257
Dial Peers (POTS & VoIP Dial Peers)
Voice Call Legs
Configuring POTS Dial Peers
Dial Peer Wildcards
Private Line Automatic Ringdown PLAR FXS PLAR FXO PLAR
Router Call Processing & Digit Manipulation
Inbound and Outbound Dial Peers
Matching Inbound and Outbound Dial Peers
Failovers & Multiple Voice Paths
Redirecting Operator Calls
Centralizing PSTN Access
Using Translation Profiles
QoS (Quality of Service) Bandwidth Delay – Fixed delay – Variable delay – Jitter (delay variations) – Packet loss End-to-end delay budget: <150 ms Jitter: 30 <30 ms Packet loss: <1%
Cisco AutoQoS Advantages over manual QoS configuration Reduces time of deployment Provides configuration consistency Reduces deployment cost Still allows for manual tuning