CCNP Voice Notes - Dials Peers and Matching OH MY!

Inbound Dial Peer Matching
3 elements in call setup message:

1. Called Number (DNIS)
2. Calling Number (ANI)
3. Voice Port - port the call is coming in on

Plus 5 configurable dial peer attributes processed top down only if one above fails to match:

1. Called number with incoming called-number.
• Tries matching on DNIS if multiple longest match wins (YAY)
2. Calling number with answer-address.
• Tries matching on ANI again if multiple longest match wins.
3. Calling number with destination-pattern.
• Tries to match DNIS to destination-pattern (think route pattern) if multiple yada yada.
4. Voice-port associated with the port parameter.
• Tries to match on port parameter if multiple dial peer first added in the config wins.
5. Last ditch, default dial peer.

*NOTES*

Use the answer-address command when matching the region of a caller, recommended situations:

• Callers from a given country should be directed to an appropriate group.
• Directing callers from a specific region to a regional support group.

Use the incoming called-number command whenever possible. All call setup messages include DNIS.

Outbound Dial Peer Matching

When a call arrives at a voice gateway, it uses the incoming dial string to match the destination-pattern on the outbound dial-peer. Once a match is found the port on POTS dial peers or session-target on VoIP dial peers is used to forward the call. MOST SPECIFIC MATCH WINS

Default Dial Peer (Don't be sad little guy you're important too)

Default dial peer referred to as dial-peer 0 (sounds ominous) it is used if no inbound dial peer can be matched, see list above. ONLY USED FOR INBOUND NEVER EVER EVER, (DON'T EVEN THINK IT) used for outbound. Characteristics of DP0 (Dial peer 0, DP0 sounds even more ominous) cannot be changed.

DP0 VoIP Characteristics

• G.729 / G.711
• IP precedence set to 0.
• VAD enabled
• RSVP not supported
• Fax-rate service supported

DP0 POTS Characteristics

• No applications supported
• No DID support

Avoid using DP0 when possible.

CCNP Voice Notes - Call Legs / Dial Peers

Call Legs
Every voice call to be completed must have a minimum of two call legs. An Incoming call leg and an Outgoing call leg.

POTS Call Leg – Connected to a non-VoIP network such as POTS line, PRI, BRI etc.
VoIP Call Leg – Connected to a VoIP network such as SIP, H.323.

Dial Peers 
Destination Pattern – Used to match the called telephone number.
Incoming Called-Number – ONLY Considered on selecting inbound dial-peer when it matches the original dialed/called number.
Answer-address – ONLY Considered on selecting inbound dial-peer when it matches the original calling number. 

Call Number aka DNIS (Dialed Number Identification Service)
Calling Number aka ANI (Automatic Number Identification)

Pattern	Description
0-9 A-D * #	All numbers that exist on the phone keypad.
Plus +	First character designates E.164 number; otherwise it specifies that the digit before occurred one or more times.
Period .	Matches any entered digit
%	The digit before occurred either zero or more times.
?	Repeats the digit before zero or one time. Press ctrl-v to disable context help to enter the ?
Circumflex ^	Indicates a match to the beginning of the string.
$	Matches the null string at the end of the string.
T	Makes router wait till all digits are collected. Means variable length.
Backslash \	Followed by a single character, matches that character.
Brackets [ ]	Indicates a range
Parentheses ( )	Indicates a pattern

Examples

Pattern	Matches
5555	Explicitly matches 5555
555.	Matches 5550 – 55559
555[3-9]	Matches 5553 – 5559
(555)?5	Matches 5 or 5555
5%555	Matches 555 or 55555…555
^5555$	Matches 5555
9T	Matches 9 – 999999999999 until digits are done being entered

CCNP Voice Notes - Call Processing / Deployment Models

Call Processing Agents

Agent	Recommended Size	Comments
Cisco CME	Up to 240 Phones	Dependent on Cisco IOS Platform
CUCM	50 – 30,000 Phones
Legacy PBX	Dependent on PBX

IPT Deployment Models

·         Single Site

o   Design Characteristics

§  30k SCCP / SIP phones per cluster

§  2,100 H.323 / MGCP gateways per cluster

§  DSP resources for transcoding / MTP as needed

o   Benefits

§  Ease of deployment

§  Common infrastructure for a converged solution

§  Simplified dial plan

§  No transcoding resources needed because of the use of a single high band-width codec.

·         Multi-site with centralized call processing

o   Design Characteristics

§  All single site Characteristics

§  Max 1000 locations per CUCM cluster

§  Max 150ms one-way latency to phones

o   Benefits

§  Single point of management

§  Cost savings using IP WAN for calls between sites

·         Multi-site with distributed call processing

o   Design Characteristics

§  All single site Characteristics

§  Max 1000 locations per CUCM cluster

§  Max 150ms one-way latency to phones

o   Benefits

§  Cost savings using IP WAN for calls between sites

§  Use of IP WAN for TEHO

§  No loss of functionality during WAN outage

·         CoW – Cluster over WAN

o   Design Characteristics

§  All single site Characteristics

§  Max 1000 locations per CUCM cluster

§  Max 150ms one-way latency to phones

§  Max 40ms one-way latency between cluster nodes

o   Benefits

§  Single point of Administration

§  Feature transparency

§  Extension mobility within cluster

§  Unified dial plan

The Road to CCNP Voice

So it's been a while I'll admit. Things have changed I have a new job with more focus VoIP / UC. In fact it's my task to cut over multiple CUCM clusters to 8.6 and along the way ditch Cisco Unity in favor of Microsoft Exchange 2010 UM.

So during this journey I plan to make some postings of useful tips I run across and also while I study for CCNP Voice I will use the blog to help myself retain some information.

That being said. PowerShell is pretty cool, never thought I'd say that but I've run across some useful commands to help me extract data from the AD side of the house to compare against Unity.

If you're in our boat you have Lync but your AD forest is still old. That being said PowerShell against AD is then off limits. Unless you cheat and use Lync to get the information for you.

Export list of Users from Lync

Import-Module Lync
Get-CsAdUser -OU "ou=Users,ou=Location,dc=blah,dc=domain,dc=com" | Select-Object SamAccountName,FirstName,LastName,Phone | Out-File C:\Users\person\Desktop\users.txt

What that lovely  command above will do is, extract all the users from the OU in a nice Tab separated file on the desktop with the following fields: Account Name, First Name, Last Name, Primary Phone Number.

Stay tuned for more details as I lose my mind during the migration and cram some CCNP Voice knowledge in. First up is the CVoice book.