SIP Trunk – Northwest Branch Training

April 2013

Todd KawamuraCenturyLink Sales Engineer

SIP Trunk – Northwest Branch Training

What we should all know about SIP Trunk

• What is SIP & brief history

• Primary advantages & benefits of SIP

• Sweet spot for SIP opportunities – What to look for

• Configuration Elements

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SIP Trunk – Northwest Branch Training

What we should all know about SIP Trunk

• What is SIP & Brief History SIP stands for “Session Initiation Protocol”

It’s an IETF standard RFC3261 first published in 2002

Based on many of the features in HTTP and SMTP protocols

SIP is the signaling protocol to setup and process VoIP calls

RTP is SIP’s companion protocol that’s used to carry the audio

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SIP Trunk – Northwest Branch Training

What we should all know about SIP Trunk

• Primary Advantages & Benefits of SIP Fault-Tolerance: Ability to build in different levels of diversity Cost-Effectiveness: Barrier to entry is low, as is marginal expense Scalability: Easy to add more capacity with SIP Flexibility: Lots of options to adjust call bandwidth, call flow, etc. Manageability: QControl gives users lots of control over SIP service Centralizability:

One vendor to deal with for PSTNConsolidation of PSTN access linesCentralized TN management

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SIP Trunk – Northwest Branch Training

What we should all know about SIP Trunk

• Sweet spot for SIP opportunities: Customer... Has QoS-enabled IP WAN now Already has a VoIP solution in place Has multiple remote/branch locations with traditional PSTN access Views telephony as business-critical to enterprise (e.g., call center) Has seasonal fluctuations or other unanticipated call-flow variations

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SIP Trunk – Northwest Branch Training

SIP Trunking Configuration Elements• SIP engineering considerations

• Session sizing

• Bandwidth sizing

• Session-by-type sizing (Usage and Flat session quantity)

• SIP Diversity options (Enterprise, Switch)

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SIP Trunk – Northwest Branch Training

ENGINEERING CONSIDERATION 1TOTAL SESSIONS REQUIRED

Determine total session (i.e., trunking) requirements for enterprise

Methods include:

o Peg counts from traffic study

o CDR data from customer’s PBX

o Rule of thumb method agreed to by customer

SIP Trunk – Northwest Branch Training

Determine how many sessions by type (Flat or Usage)

o Flat Inbound Call Types (from PSTN) : Local TN, DID

o Flat Outbound Call Types (to PSTN): Local (including 411, 711, 911)

Usage Inbound Call Types (from PSTN): 8xx, RDID

Usage Outbound Call Types (to PSTN): LD, Alien TN (non-SIP TN)

ENGINEERING CONSIDERATION 2SESSIONS REQUIRED BY TYPE

SIP Trunk – Northwest Branch Training

ENGINEERING CONSIDERATION 4TOTAL VOIP BANDWIDTH REQUIRED

For each access line, determine max sessions

Determine circuit type / L2 protocol (HDLC, PPP, Ethernet)

Determine VoIP packet sample size

Determine Qty of G.711 calls

Determine Qty of G.729 calls

Determine % of IQ circuit that is for P1 traffic

Determine % of P1 bandwidth that is VoIP (QVUR)

SIP Trunk – Northwest Branch Training

What we should all know about SIP Trunk• Diversity Options Simplified (I hope)

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SIP Trunk – Northwest Branch TrainingENGINEERING CONSIDERATION 6

DIVERSITY STRATEGYENT. SESSION POOLING, ENT. DIVERSITY, SW DIVERSITY

SIP Trunk – Northwest Branch TrainingENGINEERING CONSIDERATION 6

DIVERSITY STRATEGYENT. SESSION POOLING, ENT. DIVERSITY, SW DIVERSITY

SIP Trunk – Northwest Branch TrainingENGINEERING CONSIDERATION 6

DIVERSITY STRATEGYENT. SESSION POOLING, ENT. DIVERSITY, SW DIVERSITY

SIP Trunk – Northwest Branch TrainingENGINEERING CONSIDERATION 6

DIVERSITY STRATEGYENT. SESSION POOLING, ENT. DIVERSITY, SW DIVERSITY

SIP Trunk – Northwest Branch TrainingENGINEERING CONSIDERATION 6

DIVERSITY STRATEGYENT. SESSION POOLING, ENT. DIVERSITY, SW DIVERSITY