Dial Plan and Call Routing Demystified On Cisco Collaboration Technologies: Cisco Unified Communication Manager

By Redouane MEDDANE

Dial plan and Call Routing are the most important complex components for any Cisco Unified Communications system and deployment. Whether implementing single-site or multisite deployments, understanding the dial plan and Call Routing and the solid knowledge of how to implement them on Cisco Unified Communication Manager is essential for any voice engineer. Generally, the dial plan is the decision maker and instructs the call processing agent on how to route the calls.

When we talk about Dial Plan and Call Routing, many components are involved such route pattern, route list, route group, trunk and gateway, also Translation Pattern and Transformation Pattern for digits manipulation of the called and calling parties.

This Book is written to demystify the Dial Plan and Call Routing, especially the components that are used to implement them with atypical scenarios, to show you how translation pattern works?, how transformation pattern works?, what is the difference between them?, where to implement them?, how and where to implement digit manipulations of the called and calling parties at different level? Under route pattern, route group, at the phone level with the external phone number mask, at the gateway level, also one of the most important parts of Dial Plan is the Globalized Call Routing or Unified Dial Plan using the +164 format, the globalization is covered in details and anwser the question: Why we need the Unified Dial Plan? And how some features such as device mobility, AAR (Automated Alternate Routing), Emergency Numbers, Class of Service and TEHO (Tail Hop End Off) are simplified.

In addition, Webex Calling Cloud-Based Call Control is covered to align with the current Cisco Collaboration solutions to explain Webex Calling components, features and call routing logic with PSTN or on-premise Cisco Unified CM using Local Gateway, Trunk, Dial Plan and Route Group, and call routing with dial peers on Local Gateway.

• Language: English
• Publisher: Lulu.com
• Release date: Apr 28, 2022
• ISBN: 9781435765566

Book preview

Dial Plan and Call Routing Demystified

On Cisco Collaboration Technologies

Cisco Unified Communication Manager

Redouane MEDDANE 3xCCNP Collaboration, Security and Enterprise

Mastering a topic takes effort

Demystifying and Simplifying

takes a lot of effort

but it is worth it.

Lulu Press, Inc

Morrisville, North Carolina

Dial Plan and Call Routing Demystified On Cisco Collaboration Technologies

Cisco Unified Communication Manager

Copyright @ 2022 Redouane MEDDANE.

Published by:

Lulu Press, Inc

Morrisville, North Carolina

ISBN: 978-1-4357-6556-6

All Right Reserved. No portion of this book may be reproduced mechanically, electronically, or by any other means, including photocopying, without the written permission of the publisher.

Description:

Dial plan and Call Routing are the most important complex components for any Cisco Unified Communications system and deployment. Whether implementing single-site or multisite deployments, understanding the dial plan and Call Routing and the solid knowledge of how to implement them on Cisco Unified Communication Manager is essential for any voice engineer. Generally, the dial plan is the decision maker and instructs the call processing agent on how to route the calls.

Goals and Methods:

When we talk about Dial Plan and Call Routing, many components are involved such route pattern, route list, route group, trunk and gateway, also Translation Pattern and Transformation Pattern for digits manipulation of the called and calling parties.

This Book is written to demystify the Dial Plan and Call Routing, especially the components that are used to implement them with atypical scenarios, to show you how translation pattern works? How transformation pattern works? what is the difference between them?, where to implement them?, how and where to implement digit manipulations of the called and calling parties at different level? Under route pattern, route group, at the phone level with the external phone number mask, at the gateway level, also one of the most important parts of Dial Plan is the Globalized Call Routing or Unified Dial Plan using the +164 format, the globalization is covered in detail and answer the question: Why we need the Unified Dial Plan? And how some features such as device mobility, AAR (Automated Alternate Routing), Emergency Numbers, Class of Service and TEHO (Tail Hop End Off) are simplified.

In addition, Webex Calling Cloud-Based Call Control is covered to align with the current Cisco Collaboration solutions to explain Webex Calling components, features and call routing logic with PSTN or on-premise Cisco Unified CM using Local Gateway, Trunk, Dial Plan and Route Group, and call routing with dial peers on Local Gateway.

The Dial Plan and Call Routing on Cisco Unified Communication Server are covered with atypical explanations and scenarios so that you will get a feeling of, This is how a call is routed, and This is how a feature works.

How to read this book?

This book is a series of hands of labs, and there is no relationship between them, you can start at any lab, from the last, the first or the middle, the purpose is to provide you a granularity to freely switch between topics and go to the one you need in depth lecture and understanding.

About the Author:

Redouane MEDDANE is 3xCCNP Collaboration, Security and Enterprise certified and he is a published author of some of the most important OSPF Protocol, Security and Collaboration books in the world titled: OSPF Demystified With RFC, Network Security All-in-one, and Dial Plan and Call Routing Demystified on CUCM, Cisco Meeting Server Deploy Implement Maintain Cisco Collaboration Conferencing. He is also a blogger at ipdemystify.com and writes articles about OSPF, collaboration and security to demystify the most complex topics.

His books are known for their technical depth and accuracy especially the OSPF Demystified With RFC book, which is considered as the best OSPF book in the world and named One of the best OSPF ebooks of all time by BookAuthority.

Table of Content:

Lab 1: Translation Pattern for inter-site dialing

Lab 2: Translation Pattern to block international calls

Lab 3: Translation Pattern for Overlapping Numbers

Lab 4: Translation Pattern to Match the Calling Number

Lab 5: Originator’ s CSS in Translation Pattern

Lab 6: Call Routing using Standard Local Route Group

Lab 7: Digit manipulation of Calling Party

Lab 8: Globalization Dial Plan on CUCM

Lab 9: Globalization of Emergency Number

Lab 10: Traditional SRST Call Manager Fallback

Lab 11: Enhanced SRST CME-Based

Lab 12: Region and Call Admission Control

Lab 13: Automated Alternate Routing AAR

Lab 14: AAR with Globalized Call Routing

Lab 15: Device Mobility Without Globalized Call Routing

Lab 16: Device Mobility With Globalized Call Routing

Lab 17: Toll Fraud With CUCM and Unity Connection

Lab 18: Toll Fraud With OffNet to OffNet Transfer

Lab 19: Globalized Call Routing With Multisite Deployment

Lab 20: Tail End Hop OFF TEHO With Globalized Call Routing

Lab 21: H.323 Signaling Protocol With Wireshark

Lab 22: Firewall Traversal, NAT Traversal and MRA On Cisco Expressway

Lab 23: Auto Attendant On Cisco Unity Connection

Lab 24: Cisco Unified Border Element CUBE Diversion Header

Lab 25: Cisco CUBE Multi-tenant with Dial Peer Group and Voice Class URI

Lab 26: Extend and Connect With Cisco Jabber

Lab 27: Conference Now Feature On CUCM

Lab 28: AdHoc Conference Bridge

Lab 29: Designing Dial Plan with Separate CUCM Cluster and Single CMS Cluster

Lab 30: Designing Dial Plan With Cisco Session Management Edition for Conferencing

Lab 31: Designing and Implementing Globalized Dial Plan

Lab 32: Run On All Active Unified CM Nodes Route List vs SIP Trunk

Lab 33: Webex Calling Call Routing Logic and Integration

Appendix A: Route Pattern Translation Pattern Transformation Pattern order priority

Appendix B: Closest-Match Routing

Appendix C: Digits Manipulation on Cisco CUCM, Where and When to do it?

Appendix D: Calling Transformation Pattern at the Phone Level

Appendix E: SIP Method for Transfer Type: Release to Switch VS Supervise Transfer

Appendix F: Accept Unsolicited Notification and Accept Replaces Header

Appendix G: Transformation Pattern use case

Lab 1: Translation Pattern for inter-site dialing

Translation pattern is a powerful tool to perform digit manipulation in CUCM for calling party or called party.

Translation pattern is similar to route pattern, however with a route pattern, when the dialed digits match the route pattern, CUCM routes the call to a gateway or through a SIP trunk, with translation pattern when the dialed digits match a translation pattern, CUCM does not route the call to a gateway or SIP trunk; instead, it performs the translation first, the resulting pattern is then re-analyzed by the system in the call routing. The new pattern may match another translation pattern and so on, finally if there is no other translation pattern, then the system routes the call or the resulting pattern through a route pattern if a match is found.

The translation pattern is useful in a distributed deployment with multisite and each site has a unique site code.

In this example, we have the following requirements:

The Directory Number of the phone should be the PSTN Number with E.164 format.

Within the same cluster, the users should use the four last digits, the internal directory number, Site-1 2XXX and Site-2 3XXX. When user at HQ Phone 1 makes a call to HQ Phone 2, he dials four digits 2002.

For inter-cluster calls, the users should use six digits, site cote + four last digits, Site code of Site-1 81, Site code of Site-2 is 82. When user at HQ Phone 1 makes a call to BB Phone 1, he dials six digits 82 3002.

Access the HQ-CUCM at Site-1 with IP address 10.1.5.15.

For intra-cluster calls.

Site-1 : Create a translation pattern with a pattern 2XXX.

C:\Users\mac\Desktop\Translation pattern\1.PNG

In the Calling Party Transform Mask enter XXXX.

In the Called Party Transform mask, use +1201201XXXX.

C:\Users\mac\Desktop\Translation pattern\2.PNG

The result of this translation pattern is that when a user at Site-1 with [phone] dials 2002 for example, the dialed digits will be translated to the Directory Number [phone] because the Called Party Transform Mask and the phone rings. The calling number 2001 will be displayed because the Called Party Transform Mask.

For inter-cluster calls.

Site-1 : Create a translation pattern with a pattern 81XXXX.

C:\Users\mac\Desktop\Translation pattern\3.PNG

In the Calling Party Transform Mask enter 82XXXX.

In the Called Party Transform Mask enter +1201201XXXX.

C:\Users\mac\Desktop\Translation pattern\4.PNG

The result of this translation pattern is that when a user at Site-2 with [phone] dials 812001 for example, CUCM at Site-1 receives a call with called number 812001, the dialed digits will be translated to the Directory Number [phone] because the Called Party Transform Mask and the phone rings. The calling number 823001 will be displayed because the Called Party Transform Mask.

You should have two translation patterns, the first 2XXX is for intra-cluster calls and the second 81XXXX for inter-cluster incoming calls.

C:\Users\mac\Desktop\Translation pattern\5.PNG

Repeat the same steps for BB-CUCM at Site-2 with IP address 10.1.5.20.

For intra-cluster calls.

Site-1 : Create a translation pattern with a pattern 3XXX.

C:\Users\mac\Desktop\Translation pattern\6.PNG

In the Calling Party Transform Mask enter XXXX.

In the Called Party Transform mask, use +1301301XXXX.

C:\Users\mac\Desktop\Translation pattern\7.PNG

The result of this translation pattern, is that when a user at Site-2 with [phone] dials 3002 for example, the dialed digits will be translated to the Directory Number [phone] because the Called Party Transform Mask and the phone rings. The calling number 3001 will be displayed because the Called Party Transform Mask.

For inter-cluster calls.

Site-2 : Create a translation pattern with a pattern 82XXXX.

C:\Users\mac\Desktop\Translation pattern\8.PNG

In the Calling Party Transform Mask enter 81XXXX.

In the Called Party Transform mask, use +1301301XXXX.

C:\Users\mac\Desktop\Translation pattern\9.PNG

The result of this translation pattern, is that when a user at Site-1 with [phone] dials 823001 for example, CUCM at Site-2 receives a call with called number 823001, the dialed digits will be translated to the Directory Number [phone] because the Called Party Transform Mask and the phone rings. The calling number 812001 will be displayed because the Called Party Transform Mask.

You should have two translation patterns, the first 3XXX is for intra-cluster calls and the second 82XXXX for inter-cluster incoming calls.

C:\Users\mac\Desktop\Translation pattern\10.PNG

Make sure you have a route pattern on BB-CUCM with 81.XXXX through the SIP trunk.

C:\Users\mac\Desktop\Translation pattern\11.PNG

Make sure you have a route pattern on HQ-CUCM with 82.XXXX through the SIP trunk.

C:\Users\mac\Desktop\Translation pattern\12.PNG

Test the intra-cluster calls.

From HQ Phone 1, dial 2001.

C:\Users\mac\Desktop\Translation pattern\17.PNG

From BB Phone 1, dial 3002.

C:\Users\mac\Desktop\Translation pattern\19.PNG

For inter-cluster calls.

From HQ Phone 1, dials 823001.

C:\Users\mac\Desktop\Translation pattern\20.PNGC:\Users\mac\Desktop\Translation pattern\21.PNG

From BB Phone 1, dials 812001.

C:\Users\mac\Desktop\Translation pattern\22.PNGC:\Users\mac\Desktop\Translation pattern\23.PNG

Lab 2: Translation Pattern to block international calls

In CUCM, call privileges, also known call permissions are defined by using partition and Calling Search Space CSS. Applying a partition to a number, it means you lock access to that number. If you want to call this number you need a CSS that contains that partition.

The CSS can be applied at the phone (Device) level or at the line level.

In a multisite deployment with extension mobility or device mobility, it is important to keep the same call permissions of the users, so the recommended configuration is to apply a restrictive CSS at the line level and apply a permissive CSS at the physical phone level.

When a CSS is applied at both the line and phone level and a call is received by the CUCM, it will check the line level CSS first. If the partition of the called number is not in the line level CSS, then the CUCM will check the phone-level CSS.

Since the recommendation is to block calls at the line level, the best place to block calls is using a translation pattern.

For example international calls should be blocked while all other calls should be routed.

To accomplish this, you create a translation patterns to match international calls with the Block This Pattern option., you put it in partition, and you associate a CSS that contains this partition to Directory Number or Line, if a call matches the translation pattern, it should be blocked instead of routed.

In this example, HQ Phone 1 should have all call permissions for Internal, National, Emergency and International calls.

HQ Phone 2 has a call permission for Internal, National and Emergency calls. International calls should be blocked.

In this topology we have a cluster with a Call Manager HQ-CUCM and another cluster with BB-CUCM, to simulate a PSTN phone, Cisco IP Communicator is registered on BB-CUCM with different lines to simulate emergency, national and international calls.

The calls from the HQ Phones go through the BB-CUCM in order to reach the emulated PSTN phone, so we need a SIP trunk between HQ-CUCM and BB-CUCM.

Configure a SIP Trunk with a name Trunk-sip-to-BB between the HQ-CUCM 10.1.5.15 and the BB-CUCM 10.1.5.20.

C:\Users\mac\Desktop\digit manipulation\1.PNG

Configure a route group named RG-Trunk and add the Trunk SIP Trunk-sip-to-BB to it.

C:\Users\mac\Desktop\digit manipulation\2.PNG

Configure a single route list named RL-List and point it to the route group RG-Trunk that appears in the drop down.

C:\Users\mac\Desktop\digit manipulation\3.PNG

Create a route pattern 9.011! for international calls with interdigit timeout and point this route pattern to the route-list RL-list you created previously.

C:\Users\mac\Desktop\Translation Pattern int call\1.PNG

Create a route pattern 9.011!# for international calls without interdigit timeout and point this route pattern to the route-list RL-list.

C:\Users\mac\Desktop\Translation Pattern int call\2.PNG

Create a route pattern 9.1[2-9]XXXXXXXXX for national calls and point this route pattern to the route-list RL-list.

C:\Users\mac\Desktop\Translation Pattern int call\9.PNG

Create a route pattern 911 for emergemcy calls and point this route pattern to the route-list RL-list.

C:\Users\mac\Desktop\Translation Pattern int call\10.PNGC:\Users\mac\Desktop\Translation Pattern int call\4.PNG

Configure digit manipulation of the calling party numbers for outgoing call to PSTN to comply with a numbering plan used in PSTN, the DID used for the HQ Cluster is 508111XXXX.

Set the Calling Party Transformations in the route list detail level with Calling Party Transformation Mask 508111XXXX.

Under the Called Party Transformations, Discard Digits select NANP:PreDot to strip the PSTN Access Code 9.

C:\Users\mac\Desktop\Translation Pattern int call\5.PNG

From HQ Phone 1, place an international call 9011447777881233, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\6.PNGC:\Users\mac\Desktop\Translation Pattern int call\7.PNG

From HQ Phone 1, place a national call 914087071222, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\11.PNGC:\Users\mac\Desktop\Translation Pattern int call\12.PNG

From HQ Phone 1, place an emergency call 911, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\14.PNG

From HQ Phone 2, place an international call 9011447777881233, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\8.PNG

From HQ Phone 2, place a national call 914087071222, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\13.PNG

From HQ Phone 2, place an emergency call 911, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\15.PNG

Create five partitions with the following names :

Internal-PT

National-PT

Emergency-PT

International-PT

Block-International-PT

C:\Users\mac\Desktop\Translation Pattern int call\16.PNGC:\Users\mac\Desktop\Translation Pattern int call\18.PNG

Create a CSS named Unrestricted-CSS-1 and from the Available Partitions tab, move the partitions Internal-PT, National-PT, Emergency-PT and International-PT to the Selected Partitions tab.

C:\Users\mac\Desktop\Translation Pattern int call\19.PNG

Create a CSS named Unrestricted-CSS-2 and from the Available Partitions tab, move the partitions Internal-PT, National-PT and Emergency-PT to the Selected Partitions tab.

C:\Users\mac\Desktop\Translation Pattern int call\20.PNG

Create a CSS named Block-International-CSS and from the Available Partitions tab, move the partition Block-International-PT to the Selected Partitions tab.

C:\Users\mac\Desktop\Translation Pattern int call\21.PNGC:\Users\mac\Desktop\Translation Pattern int call\22.PNG

In the Route Patterns Configuration, associate the appropriate partitions.

C:\Users\mac\Desktop\Translation Pattern int call\23.PNG

Edit the Route Pattern 9.011!, in the Route Partition field, select International-PT.

C:\Users\mac\Desktop\Translation Pattern int call\24.PNG

Edit the Route Pattern 9.011!#, in the Route Partition field, select International-PT.

C:\Users\mac\Desktop\Translation Pattern int call\25.PNG

Edit the Route Pattern 9.1[2-9]XXXXXXXXX, in the Route Partition field, select National-PT.

C:\Users\mac\Desktop\Translation Pattern int call\26.PNG

Edit the Route Pattern 911, in the Route Partition field, select Emergency-PT.

C:\Users\mac\Desktop\Translation Pattern int call\27.PNG

You should obtain the following output.

Route Pattern 9.011! in International-PT partition.

Route Pattern 9.011!# in International-PT partition.

Route Pattern 9.1[2-9]XXXXXXXXX in National-PT partition.

Route Pattern 911 in Emergency-PT partition.

C:\Users\mac\Desktop\Translation Pattern int call\28.PNG

Create a Translation Pattern to block international calls with the following settings:

Pattern: 9.011!

Partition: Block-International-PT

Route Option: Block this pattern

C:\Users\mac\Desktop\Translation Pattern int call\29.PNGC:\Users\mac\Desktop\Translation Pattern int call\30.PNG

Go the Phone page, edit the HQ Phone 1.

C:\Users\mac\Desktop\Translation Pattern int call\31.PNG

The phone level CSS contains partitions that allow all PSTN calls to be routed.

Under Calling Search Space field, select Unrestricted-CSS-1.

Unrestricted-CSS-1 contains the partitions: Internal-PT, National-PT, International-PT and Emergency-PT.

C:\Users\mac\Desktop\Translation Pattern int call\32.PNG

Edit the HQ Phone 2.

Under Calling Search Space field, select Unrestricted-CSS-2.

Unrestricted-CSS-2 contains the partitions: Internal-PT, National-PT, and Emergency-PT.

C:\Users\mac\Desktop\Translation Pattern int call\33.PNG

The line-level CSS of a HQ phone 2 should have the CSS that contains the blocking partition for international calls.

In the Directory Number Configuration, under the Directory Number Settings, select Block-International-CSS in the Calling Search Space field.

Block-International-CSS contains the Block-International-PT Partition.

C:\Users\mac\Desktop\Translation Pattern int call\34.PNG

From HQ Phone 1, place an internal call 2002, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\38.PNG

From HQ Phone 1, place an emergency call 911, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\35.PNG

From HQ Phone 1, place a national call 914087071222, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\36.PNG

From HQ Phone 1, place an international call 9011447777881233, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\37.PNG

From HQ Phone 2, place an internal call 2001, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\41.PNG

From HQ Phone 2, place an emergency call 911, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\39.PNG

From HQ Phone 2, place a national call 914087071222, the call should be successful.

C:\Users\mac\Desktop\Translation Pattern int call\40.PNG

From HQ Phone 2, place an international call 9011447777881233, the call should fail.

C:\Users\mac\Desktop\Translation Pattern int call\42.PNG

The HQ Phone 2 displays the message Cannot reach the number.

C:\Users\mac\Desktop\Translation Pattern int call\43.PNG

To confirm, use the Dialed Number Analyzer tool in Cisco Unified Communications Manager (CUCM). the Dialed Number Analyzer is very cool tool to test a complex dial plan with many CSS, Partitions, Route Groups, Route Lists, Route Patterns, etc.

It helps you to analyze a dial plan and gives the full call flow information for the dialed digits.

To use the Dialed Number Analyzer tool, access Cisco Unified Serviceability menu , then navigate to Tools → Service Activation and check Cisco Dialed Number Analyzer and click Save.

Now navigate to Tools → Dialed Number Analyzer.

Select the HQ Phone 2 and check Line [1] – 2002 check boxes.

In the Dialed Digits, enter the international number 9011447777881233.

Click Do Analysis.

C:\Users\mac\Desktop\Translation Pattern int call\44.PNG

A new window appears, which is the result of the Dialed Number Analyzer.

You should see the Match Result = BlockThisPattern.

C:\Users\mac\Desktop\Translation Pattern int call\45.PNGC:\Users\mac\Desktop\Translation Pattern int call\46.PNG

As mentioned previously, In a multisite deployment with extension mobility or device mobility, it is important to keep the same call permissions of the users. It is recommended to apply a restrictive CSS at the line level and apply a permissive CSS at the physical phone level.

Let’s test this approach, the BB Phone 1 located at the Branch site is already registered with a Directory Number 3001 in the HQ-CUCM located at the Central HQ site.

When the user John Smith associated with the HQ Phone 2, moves to the branch site and he log in on the BB Phone 1, the same call permissions should be applied, in other words, the international calls should be blocked.

Create an End User with the following settings :

User ID: jsmith

Password: Cisco123